type genetic sequences exchanged similar identical molecules dna widely cells accurately repair harmful breaks occur strands dna known double strand breaks produces new combinations dna sequences process cells like sperm egg cells animals new combinations dna represent genetic variation offspring turn enables populations adapt course evolution horizontal gene transfer exchange genetic material different strains species bacteria varies widely different organisms cell types forms involve basic steps double strand break occurs sections dna ends break cut away process called strand invasion step follows end broken dna similar identical dna broken strand invasion sequence events follow main pathways discussed models double strand break repair synthesis dependent strand occurs dna repair tends result non crossover products effect restoring damaged dna existed double strand break domains life suggesting nearly universal biological mechanism discovery genes diverse group interpreted evidence emerged early evolution strongly associated increased types cancer proteins facilitate topics active research gene targeting technique introducing genetic changes target organisms development technique mario martin evans oliver awarded nobel prize physiology medicine independently discovered applications mouse stem cells highly mechanisms underlying repair model including uniform integration transformed dna gene therapy shown experiments researching induced led later experiments cut genetic engineering cells frequent history discovery early 1900s william found exception principles inheritance originally described 1860s contrast notion traits independently passed parent child example cat hair color tail length inherited independent showed certain genes associated physical traits inherited genetically linked observing linked traits occasion inherited separately thomas hunt morgan suggested occur linked genes linked genes physically crosses different decades later barbara demonstrated crossover occurs process cell division sperm egg cells year discovery stern showed crossing later called occur cells like white blood cells skin cells divide showed bacteria assumed reproduce capable genetic similar sexual reproduction work established model organism helped win nobel prize physiology medicine building studies fungi robin proposed model introduced key details process work including exchange material junctions jack colleagues presented model known accounted observations explained model decade experiments cells led emergence models called pathways rely junctions essential cell division like plants animals fungi cells divide repairs double strand breaks dna caused radiation dna damaging chemicals left double strand breaks cause large scale cells turn lead cancer addition repairing dna helps produce genetic diversity cells divide specialized cells sperm egg cells animals plants spores fungi crossover regions similar identical dna exchanged creates new possibly beneficial combinations genes offspring evolutionary advantage crossover begins protein called makes targeted double strand break dna sites non randomly located usually promoter regions rich domains double strand break sites occur regions base pairs length high rates absence genes means genes inherited future generations equal proportion represents genes greater expected genes independently timing cell cycle double strand breaks repaired non end joining dna repair mechanism unlike require long sequence guide repair repair double strand breaks largely determined phase cell cycle repairs dna cell enters phase occurs shortly dna phases cell cycle sister easily available compared similar different sister ideal template identical copy given contrast predominant phase cell cycle cell growing ready divide occurs frequently phase maintains activity cell cycle mechanisms regulate cell cycle vary widely species dependent modify activity proteins adding groups important dna begins dependent begins protein activated addition uses activity clean cut near double strand break dna allows protein known complex dna begins series protein driven reactions exchange material dna molecules models primary models repairs double strand breaks dna double strand break repair called double junction model synthesis dependent strand pathways similar steps double strand break occurs complex complex humans dna break dna ends break cut carried distinct steps step complex recruits protein proteins trim ends break create short single strand dna second step continued double strand dna activity allows cut single stranded dna produced protein high affinity single stranded dna help proteins process protein forms acid protein single strand dna coated begins searching dna sequences similar finding sequence single stranded moves similar identical recipient dna process called strand invasion cells divide recipient dna generally sister identical damaged dna provides template repair recipient dna tends similar necessarily identical displacement loop loop formed strand invasion invading strand strand invasion dna extends end invading strand new dna changes loop cross shaped structure known junction following dna synthesis occurs invading strand original effectively restoring strand displaced strand invasion stages strand invasion dna synthesis pathways distinct unique second involved strand invasion forms junction double junctions converted products type restriction cuts dna strand commonly results crossover result non crossover products ability broken dna collect sequences separated donor shown induction events tendency crossover likely model crossover occurs results crossover determined double junction cut resolved crossover occur junction cut crossing strand junction cut non crossing strand figure horizontal purple junction vertical orange alternatively junctions cut crossing strands horizontal purple junctions figure crossover produced occurs cells divide results non crossover products model invading strand extended recipient dna dna released junction donor recipient dna molecules process called branch migration newly synthesized end invading strand able damaged base pairing strands small dna remain flaps removed finishes known remaining single stranded gaps major repairing dna double strand breaks appears produces non crossover figure non crossover occur frequently appear arise mainly non crossover events occurring likely reflect instances repair dna double strand damages types dna damages single strand repairs double strand breaks repeat sequences unique require separate similar identical dna like pathways instead requires single dna uses repeat sequences identical sequences needs repair relatively simple concept strands dna cut site double strand break resulting align restoring dna continuous dna double strand break cut single stranded produced coated protein prevents sticking protein called repeat sequences break enable repeat sequences complete non flaps cut away set known brought flaps proteins new dna synthesis fills gaps dna continuous strands dna sequence repeats lost repeats considered results genetic material dna double strand breaks encountered dna template strand defects repaired break induced precise molecular mechanisms remain unclear proposed mechanisms strand invasion initial step differ model migration loop later phases help maintain length regions dna end absence cooperation working copies typically cycle eventually blocks cell division leads cells types survivor cells observed avoid longer expected pathways maintaining length critical cell key feature cancer maintain types human cancer like helps sustain acting alternative mechanism maintenance fact led scientists investigate based mechanisms maintenance anti cancer drugs like bacteria major dna repair process bacteria important producing genetic diversity populations process differs substantially repairs dna damages brings diversity studied best understood double strand dna breaks bacteria repaired breaks occur dna strands known single strand gaps thought repaired pathways include series reactions known branch migration single dna strands exchanged molecules dna resolution molecules dna cut apart restored normal double stranded state main bacteria repair double strand breaks dna proteins found broad array bacteria double strand breaks caused light radiation chemical double strand breaks arise dna single strand nick gap situation causes known collapsed fork fixed pathways including complex called binding blunt nearly blunt end break double strand dna dna end begin dna activity domain cuts single strand dna emerges process continues encounters specific sequence known site encountering site activity changes drastically dna seconds resumes roughly half initial speed likely slower dna faster dna recognition site changes cuts dna strand begins loading multiple proteins single stranded dna newly generated end resulting coated searches similar sequences dna search process stretching dna recognition mechanism termed finding sequence single stranded moves recipient dna process called strand invasion invading causes strands recipient dna displaced form loop loop cut strands forms cross shaped structure called junction resolution junction combination produce dna molecules genetic types interacting dna molecules differ genetically alternatively invading end near prime dna synthesis form fork type resolution produces type non bacteria appear use repair single strand gaps dna additional repair dna double strand breaks dna strand end leaving strand end intact protein strand aided proteins stabilized searches dna exchanges places identical nearly identical strand dna proteins specific mechanisms involved initial phases differ pathways similar require single stranded dna end protein strand invasion pathways similar phases branch migration junction direction resolution junctions apart alternative non type resolution occur branch migration immediately strand invasion junction moves linked dna branch migration process movement junction base pairs dna exchanged branch migration protein recognizes junction recruits protein form complex sets protein form ring shaped loaded opposite sides junction act twin pumps provide force branch migration rings sets protein assemble center junction dna junction set strands dna donor recipient surface guided protein resolution resolution phase junctions formed strand invasion process cut restoring separate dna molecules complex interacting form complex cuts sequence sequence found frequently dna cutting likely gains access junction displacing covering dna results patch products depending junction products crossover products genetic material site patch products hand non crossover products patch hybrid dna product genetic transfer important method integrating donor dna recipient organism horizontal gene transfer process organism incorporates foreign dna organism offspring organism requires incoming dna highly similar recipient horizontal gene transfer usually limited similar bacteria studies species bacteria established log linear decrease frequency increasing difference sequence host recipient dna dna transferred bacteria direct cell cell contact helps integrate foreign dna host promotes dna converted single strand dna form originally enters double strand dna essential final phase type horizontal gene transfer dna transferred virus foreign dna head virus particles dna packaged new viral new bacteria dna previous host injected new host double strand dna incorporates double strand dna new host transformation natural transformation involves transfer dna donor recipient donor recipient species transformation unlike depends numerous gene products specifically interact perform process transformation clearly adaptation dna transfer order integrate donor dna resident enter special state termed gene family plays central role transformation instance protein essential transformation expression gene induced development transformation organisms transformation process protein entering single stranded dna form scan resident regions bring entering corresponding region strand exchange occur process transformation fundamental similarities occurs groups dna occurs break rejoin mechanism like bacteria evidence specifically positive sense like controversy occurs negative sense like precise precise type difference parental sequences resulting crossover region difficult determine location crossover events sequences crossover region difference parental sequences caused addition modification level precision crossover controlled sequence context strands sequences rich decrease crossover precision important viral evolution example different undergo able fully functional alternatively similar infected host cell allow swap genes evolve potent variations proposed mechanism dna virus human human containing lethal damage host cell virus pair undergo repair produce viable process known studied including employed repair employed repair particular regard gene necessary strand exchange reaction key step repair functional humans bacteria including humans demonstrated numerous effects proper incorrectly align phase cell division causes fail properly process called turn cause sperm syndrome caused extra copy result failure deficiencies strongly linked cancer formation humans example cancer related diseases bloom syndrome syndrome syndrome caused copies genes involved regulation respectively cells bloom syndrome patients lack working copy protein elevated rate experiments mice suggested gives rise cancer loss caused increased loss refers loss versions gene lost helps suppress like gene protein example loss lead cancer decreased rates cause inefficient dna repair lead cancer case similar genes linked considerably increased risk breast cancer cells missing decreased rate increased sensitivity radiation suggesting decreased leads increased cancer known function help initiate researchers speculated detailed knowledge role key understanding causes breast cancer evolutionary conservation pathways vary ability organisms perform universally domains life based similarity acid sequences number proteins found multiple domains life indicating evolved long time ago diverged common ancestral proteins family members found organisms bacteria related single stranded binding proteins important processes found domains life number proteins found family proteins family proteins thought descended common ancestral family contains protein bacteria proteins proteins studies modeling evolutionary relationships proteins indicate share common molecular ancestor protein family grouped separate clade reasons grouping proteins possess modified turn motif helps proteins dna terminal ends ancient gene event gene subsequent proposed likely origin modern genes proteins generally share long region known domain protein domain sequence motifs walker motif walker motif walker motifs allow members protein family engage binding specific proteins discovery species earliest suggests emerged early evolution addition research studies protein provided information origins type initiate making targeted double strand breaks dna phylogenetic trees based sequence genes similar animals fungi plants led scientists believe version currently emerged common ancestor technological applications gene targeting methods introducing dna sequences organisms create dna genetically modified organisms use process called gene targeting method especially common mouse gene targeting method knockout mice uses mouse stem cells deliver artificial genetic material interest target gene mouse principle mouse acts working model understand effects specific gene recognition discovery introduce genetic modifications mice stem cells mario martin evans oliver awarded nobel prize physiology medicine advances gene targeting technologies mechanics cells leading development new wave accurate human disease models engineered human cell models thought accurately reflect human diseases mouse model predecessors largely interest introduced genes occur real patients based human rat furthermore certain technologies enable knock particular knock outs associated older gene targeting technologies protein engineering protein engineering develops proteins fragments parental proteins techniques exploit fact introduce high degree sequence diversity preserving protein ability fold structure dimensional shape stands contrast protein engineering techniques like random point probability maintaining protein function declines increasing acid produced techniques able maintain ability fold swapped parental fragments structurally building blocks preserve structurally important interactions like points physical contact different protein structure methods like statistical analysis identify structural suitable techniques rely engineer new proteins study published researchers able create involved diverse class compounds including visual certain proteins acquired ability essential reaction diverse pathways found nature absent parent proteins protein engineering produced new function members group proteins known family humans involved foreign compounds like drugs food cancer therapy cancer cells deficiencies drugs exploit deficiencies developed successfully clinical trials stopped growth breast caused genes necessary absent types dna repair mechanisms compensate base repair stalled non end joining double strand breaks cell applies concept synthetic specifically target cancer cells represent novel approach cancer therapy researchers cautioned prove insufficient treating late stage cancer cells resistant undergo drug synthetic restoring cancer cells ability repair dna


dynamics spheres ancient medieval renaissance philosophers developed different theories dynamics spheres explained motions spheres terms materials external internal motive souls impressed forces models incorporated analyses related speed motive force resistance material natural motions considering physics spheres scholars followed different views material composition spheres regions fire account fire mobility later maintained fire moves naturally upward straight line natural place periphery universe arrived rest naturally circle account compatible aristotle fiery region upper air dragged underneath circular motion lunar sphere aristotle spheres entirely special fifth element bright upper atmosphere gods distinct dense lower atmosphere terrestrial elements earth water air fire gave rise generation corruption natural substances mutual moving uniform circular motion uniquely suited spheres eternal earth water natural expressed moving downward center universe fire air natural moved upward away center heavy light moved naturally center causes motion early philosophers considered heavens moved agents believed cause world soul created according mathematical principles governed daily motion heavens motion opposed motions planets motion different aristotle proposed existence divine act final causes spheres mimic best moving uniform circular motion aristotle maintained individual required individual motion heavens number spheres gods subject revision estimated total depending followed model heavens aristotle presented alternate view eternal circular motion moving manner world soul lent support principles motion internal soul external material later greek rejected concept external prime maintaining instead planets souls voluntary motion planet sends motive emissions direct motion motions system bird sends emissions nerves direct motions feet wings john considered heavens fire maintained circular motion natural motions fire theological work creation world denied heavens moved soul angels proposing impossible god created things motive force moon sun stars heavy light bodies movements internal soul living beings order angels force interpreted application concept impetus motion spheres earlier commentary aristotle physics compared innate power nature accounts rotation heavens innate power nature accounts fall rocks islamic persian philosophers following maintained aristotle called came series beginning god intelligence god intelligence sphere soul second intelligence process continued spheres sphere moon soul final intelligence considered sphere moved continually soul seeking emulate perfection intelligence maintained intelligence soul sphere moved natural interpreter aristotle muslim spain proposed radical transformation astronomy away spheres driven single periphery universe spheres moved natural motion power diminished increasing distance periphery lower spheres daily motion earth power reached far sphere water producing tides influential later christian teachings agreed souls combine spheres rejected concept considering soul acts maintained soul moves sphere effort material tendency contrary motion later century commentator islamic theologian din rejected non religious science astronomy following ash doctrine maintained physical effects caused directly god natural causes maintained spheres imaginary things spider web medieval western_europe early middle ages picture heavens dominant european philosophers led christian question role nature world soul recovery aristotle works twelfth thirteenth centuries aristotle views supplanted earlier new set questions relationships spheres god emerged early phases western recovery aristotle robert influenced medieval astronomy rejected idea heavens moved souls adam marsh treatise flow sea attributed maintained opinion spheres seas moved peripheral motion distance thomas following interpreted aristotle mean substances responsible motion sphere soul integral sphere intelligence separate sphere soul shares motion sphere causes sphere love desire separate intelligence moses christian philosophers identified aristotle angels revelation angel spheres rejected idea bodies moved internal nature similar moves terrestrial bodies souls spheres controversial animals philosophers came reject idea spheres souls robert discussed alternative explanations motions spheres rejecting views bodies animated moved spirits souls bodies moved spirits govern maintained instead bodies moved natural similar weight heavy bodies naturally moved weight active principle bodies naturally moved similar principle heavens spherical motion natural rotation idea earlier held oxford scholar john slightly different discussions john suggested god created spheres began circular impetus corrupted diminished movements resistance region noted allow god rest seventh day left matter resolved explained motion spheres traditional terms action noted contrary aristotle moved example intelligence moves moon shares motion lunar embedded related spheres motions proportion motive power resistance impressed sphere god created heavens discussing relation moving power intelligence resistance sphere circular velocity said ratio ought called ratio force resistance analogy intelligence moves heavens resist according grant consider force resistance model properly applicable motion bodies thought terms force resistance end middle ages common opinion philosophers bodies moved external angels kind internal transformed astronomy moving earth center universe retained traditional model spheres medieval views causes motion follows aristotle maintain circular motion natural form sphere appears accepted traditional philosophical belief spheres moved external eliminated spheres held planets moved external motive power located sun motive soul associated planet early manuscript discussing motion mars considered sun cause circular motion planet attributed inward outward motion planet transforms overall motion circular oval moving soul planet motion natural motion writings attributed kind intelligence motive associated stars aftermath planets came seen bodies moving freely subtle medium continued maintain associated planets spheres


history observation known history observation goes appeared oldest appearance recorded additional way galaxy recorded time recent observed galaxy development field discovery expanded occurrences provide important information distances successful models behavior developed role star formation process increasingly understood early history explosion formed remnant likely occurred years ago nasa suggested inhabitants southern hemisphere witnessed explosion recorded symbolically year later archaeologist george recalled ancient markings left native americans carvings showed small circles flanked larger circles smaller circles resemble stellar larger circles represent star circle located near position remnant george suggested represent explosion witnessed indigenous residents chinese recorded appearance bright star sky observed took months fade sky observed like star heavens like observations consistent appearance believed oldest confirmed record event possibly recorded roman literature records survived shell suspected remnant event recent ray studies good match expected age chinese recorded appearance guest star modern additional unconfirmed events observed associated remnant remain candidates span years chinese recorded total candidate events including later explosions noted islamic european possibly indian observers appeared southern year recorded star appear night sky presence noted china egypt iraq italy japan switzerland noted france syria north_america egyptian physician ali ibn gave star quarter moon modern discovered faint remnant explosion determined light years earth widely observed event arab chinese japanese recording star appearance recorded explosion appeared produced crab remnant peak times bright venus remained visible daylight days visible night sky days fewer records occurred century noted chinese japanese stellar event danish noted careful observations night sky observatory island noted appearance new star later called associated remnant 1960s common belief europe period idea world moon planets observers argued phenomenon earth atmosphere noted object remained stationary night night changing lie far away published observations small book nova latin concerning new previously unseen star title book modern word nova variable stars derived recent seen way galaxy observed october people noted sudden appearance star noted systematic study object published observations work nova like tried vain measure new star argued view heavens remnant identified mount wilson observatory observation true nature remained obscure time observers slowly came recognize class stars undergo long term periodic fluctuations john russell hind norman charted stars underwent sudden changes received little attention astronomical community finally english william observations nova discovering lines hydrogen unusual spectrum nova proposed explosion underlying mechanism efforts drew interest nova like observed direction galaxy estonia increased 6th magnitude entire nucleus galaxy faded manner like nova george measured distance galaxy discovered lay farther previously thought meant lie line sight galaxy actually resided nucleus released greater energy typical nova early work new category nova performed 1930s walter mount wilson observatory identified considered typical explosive event released radiation approximately equal sun total energy output years decided new class super energy generated collapse ordinary stars stars super lecture publicly meeting american physical society lost modern use relatively rare events occurring average years way observations distant allowed discovered examined frequently detection patrol begun joined johnson observatory discovered new years comparing new photographic plates reference images regions walter identify remnant suggested crab remains noted appearance measured velocity expansion large belong classification year proposed use type secondary distance indicator later work helped process type type standard measuring large distances classification distant performed categorized types based lines element hydrogen appeared spectrum later proposed additional types iii longer appear associated single peculiar types sub division categories resulted modern classification scheme aftermath second world war fred worked problem observed elements universe produced proposed massive star generate necessary reactions nuclear reactions heavy elements responsible removal energy necessary collapse occur collapsing star unstable produced explosive expulsion elements distributed space concept rapid nuclear fusion source energy explosion developed william 1960s computer controlled search begun 1960s northwestern university built inch observatory new_mexico computer control displayed new galaxy minute observers checking view television screen means discovered period years modern standard model type explosions founded proposal based mass transfer scenario companion star particular light curve observed year followed long discover broad faded nearly constant rate day translated system units nearly decay rate half life days explosion model production solar mass exploding star half life days decay provides energy away late history agreement total energy production fade rate theoretical models observations led rapid acceptance explosion model observation light curves type discovered appear common peak measuring events distance host galaxy estimated good accuracy category highly useful standard measuring cosmic distances high search project discovered distant type appeared expected provided evidence expansion universe accelerating observed way appears exploded years ago year remnant explosion heavily obscured dust possibly notable appearance observed parts spectrum currently radio source solar system large cloud observed hours start detected observed band electromagnetic spectrum relative proximity allowed detailed observation provided opportunity modern theories formation tested observations rate discovery steadily increased twentieth century 1990s automated search programs initiated observatory search program begun observatory joined year berkeley automated imaging program succeeded automatic imaging observatory primarily observatory search loss program resulted discovery making world successful search program late 1990s proposed recent remnants found looking gamma rays decay half life years gamma rays traverse galaxy easily permits remnants millennium sources found previously discovered remnant remnant discovered overlapping remnant remnant found apparently larger remnant gamma rays decay showed exploded fairly recently historical record gamma rays rays indicates relatively close surprising event away estimated occur years present discovered forming galaxy appearance studied real time posed major physical questions massive limit allow observed september occurred galaxy called million light years away largest confirmation october observed explosion times previously observed star estimated times massive sun characteristics type hydrogen found spectrum thought likely candidate pair instability discovered robert discovered twice bright times bright normal type announced time caught camera exploding chance burst rays noticed looking galaxy million light years earth variety aimed direction time capture named eventually confirmed big ray blast marked birth said princeton_university amateur looking caroline moore member observatory search team found late november age declared youngest person find january year old aurora gray canada reported discovered making youngest find gray father friend spotted magnitude galaxy million light years away researchers found ice antarctica depths corresponding known apparently formed nitrogen created gamma rays technique able detect going thousand years november nasa ray observatory announced viewing remnant galaxy discovered object young year old black hole nasa noted possibility object spinning star producing wind high energy particles august factory automated survey discovered new type galaxy shortly burst existence million away detected early event started allow scientists learn early developments types march type designated discovered january students university london observatory spotted exploding star nearby galaxy cigar galaxy distance million light years nearest observed recent decades future estimated rate production galaxy size way years higher actual observed rate implying portion events obscured earth dust deployment new instruments observe wide range electromagnetic spectrum means event certainly detected


type type results rapid collapse violent explosion massive star star times times mass sun undergo type explosion distinguished types presence hydrogen spectrum type mainly observed spiral arms regions elliptical stars generate energy nuclear fusion elements unlike sun massive stars possess mass needed fuse elements atomic mass greater hydrogen albeit increasingly higher temperatures pressures causing increasingly shorter stellar life spans pressure energy generated fusion reactions sufficient counter force gravity prevent star collapsing maintaining stellar star increasingly higher mass elements starting hydrogen progressing periodic table core iron produced fusion iron produces net energy output fusion place leaving iron core lack energy output creating outward pressure broken core compressed mass star mass core exceeds limit electron longer sufficient counter compression core takes place seconds support inner core outer core collapses gravity reaches velocity speed light sudden compression increases temperature inner core billion formed reversed beta decay releasing foe second burst collapse inner core halted causing rebound bounce outward energy expanding shock wave sufficient disrupt stellar material accelerate escape velocity forming explosion shock wave extremely high temperature pressure rapidly dissipate present long allow brief period production elements heavier iron occurs depending initial size star remnants core form star black hole underlying mechanism resulting nova described core collapse exist categories type explosions categorized based resulting light curve versus time following explosion type steady linear decline light curve following explosion type display period slower decline plateau light curve followed normal decay type type core collapse massive star shed outer envelope hydrogen type result appear lacking elements formation stars far massive sun evolve complex ways core star hydrogen fused releasing thermal energy heats sun core provides outward pressure supports sun layers collapse process known stellar produced core temperatures core high cause fuse eventually hydrogen core exhausted fusion starts slow gravity causes core contract raises temperature high initiate shorter phase fusion accounts star total lifetime stars fewer solar masses carbon produced fusion fuse star gradually white dwarf white dwarf stars near companion type larger star massive create temperatures pressures needed cause carbon core begin fuse star contracts end burning stage massive stars layered like progressively heavier atomic build center layer hydrogen gas surrounding layer hydrogen surrounding layer carbon triple alpha process surrounding layers fuse progressively heavier elements star massive undergoes repeated stages fusion core stops core collapses pressure temperature sufficient begin stage fusion halt collapse core collapse factor limiting process energy released fusion dependent binding energy holds atomic additional step produces progressively heavier release progressively energy addition carbon burning onwards energy loss production significant leading higher rate reaction place continues produced course months iron highest binding energy elements energy produced core fusion iron core grows core huge pressure fusion raise star temperature support collapse supported pressure state matter dense require occupy energy states forbidden identical particles electron phenomenon called exclusion principle core mass exceeds limit pressure longer support catastrophic collapse outer core reaches speed light collapses center star rapidly core heats producing high energy gamma rays iron free core density increases favorable merge beta decay producing elementary particles called rarely interact normal matter escape core carrying away energy accelerating collapse proceeds core outer layers star absorbed star outer layers beginning explosion type collapse eventually halted short range interactions strong force pressure density comparable atomic nucleus collapse stops matter rebounds producing shock wave outward energy shock heavy elements core reduces energy shock stall explosion outer core core collapse phase dense energetic able escape combine form means electron capture electron produced typical type newly formed core initial temperature billion times temperature sun core thermal energy shed stable star form away accomplished release thermal form pairs total times number electron capture production mechanisms convert potential energy collapse second burst releasing foe process clearly understood foe energy released form stalled shock producing explosion generated observed case leading conclude core collapse picture basically correct water based instruments detected thermal origin based instrument detected number thermal electron capture origin star depending strength explosion material falls remnant core collapse star mass remnant collapses form black hole theoretical limiting mass type core collapse scenario mass star believed collapse directly black hole forming explosion models collapse calculation limits uncertain theoretical models standard model particle physics theory describes known fundamental interactions elementary particles matter theory allows predictions particles interact conditions energy particle typically tens hundreds particle energy involved small predictions gained standard model particle physics likely basically correct high require standard model particular earth based particle produce particle interactions higher energy found experiments involve individual particles interacting individual particles likely high produce novel effects interactions particles place weak nuclear force believed understood interactions involve strong nuclear force understood major problem type understood burst transfers energy rest star producing shock wave causes star explode discussion percent energy needs transferred produce explosion explaining percent transfer occurs proven difficult particle interactions involved believed understood 1990s model involved convective suggests convection matter completes process destroying star heavier elements iron formed explosion capture pressure pressing boundary surrounding space cloud gas dust richer heavy elements material star originally formed physics modeled standard model crucial understanding process crucial area investigation makes dying star core collapse determines shock wave forms stalls fact theoretical models incorporate instability stalled shock known standing shock instability instability comes consequence non spherical stalled shock tandem theories computer stalled shock computer models successful calculating behavior type shock formed ignoring second explosion assuming explosion started able detailed predictions elements produced expected light curve light curves type type spectrum type examined normally displays absorption lines reduced characteristic frequencies hydrogen absorb energy presence lines distinguish category type type plotted period time shows characteristic rise peak followed decline light curves average decay rate day lower decay rate type type sub divided classes depending shape light curve light curve type shows steady linear decline following peak contrast light curve type distinctive flat stretch called plateau decline representing period slower rate net decay rate lower day type compared day type difference shape light curves believed caused case type expulsion hydrogen envelope star plateau phase type change exterior layer shock wave hydrogen outer envelope stripping electron hydrogen resulting significant increase prevents inner parts explosion escaping hydrogen sufficiently outer layer transparent type denotes narrow indicates presence intermediate narrow width lines intermediate width case explosion interacting strongly gas star medium estimated density required explain properties higher expected standard stellar evolution theory generally assumed high density high mass loss rates estimated mass loss rates typically higher indications originate stars similar blue large mass losses exploding famous examples type extremely energetic example type type weak hydrogen line initial spectrum classified type later second peak light curve spectrum closely resembles type giant star lost hydrogen envelope interactions companion system leaving core consisted entirely type expands hydrogen layer quickly transparent reveals deeper layers classic example type example class introduced theoretical concept rare type substantially energetic standard examples type type produced type event jets formation black hole material star core model interaction dense envelope material model highest mass pair instability possibly star model stars initial masses times sun develop large explosion material fall star core create black hole cases reduces star collapses directly black hole explosion spinning quickly material generates jets energy original explosion seen directly giving impression object cases produce gamma ray bursts gamma ray bursts cases type occurs star surrounded dense cloud material likely expelled blue variable material shocked explosion standard likely range type qualifying pair instability occur oxygen core extremely massive star hot gamma rays spontaneously produce electron pairs causes core collapse collapse iron core causes fusion heavier elements collapse oxygen core creates runaway fusion completely star total energy emitted depends initial mass core converted ejected powers months lower end stars produce long lived typical highest mass stars produce extremely long lived massive stars die population iii stars low reach stage stars heavy elements blow away outer layers small explode normal type thought galaxy old low stars form massive stars capable creating pair instability


potential cultural impact extraterrestrial contact cultural impact extraterrestrial contact corpus changes terrestrial science technology religion politics ecosystems resulting contact extraterrestrial civilization closely related study cultural impact extraterrestrial contact distinct search extraterrestrial intelligence attempts locate intelligent life opposed analyzing implications contact life potential changes extraterrestrial contact vary greatly magnitude type based extraterrestrial civilization level technological advancement degree level mutual humanity medium humanity contacted electromagnetic radiation direct physical interaction extraterrestrial influence results contact incorporating factors systems created assess implications extraterrestrial contact implications extraterrestrial contact particularly superior civilization likened meeting vastly different human cultures earth historical precedent exchange meetings generally led destruction civilization receiving contact opposed contact destruction human civilization possible outcome absence verified public contact date means largely speculative background search extraterrestrial intelligence detect extraterrestrial radio identify artificial coherent signal background natural phenomena produce radio waves capable include observatory puerto_rico newer allen array hat creek california programs detect extraterrestrial intelligence government funding past project commissioned nasa 1970s investigate effective way search signals intelligent extraterrestrial sources report recommendations set aside favor modest approach extra terrestrial intelligence sending messages intelligent extraterrestrial beings intercept nasa drastically reduced funding programs turned private donations continue search discovery late 20th early 21st centuries numerous planets governments interested funding new programs european space agency launched spacecraft dedicated search nasa launched space observatory purpose february detected confirmed potentially discovered institute resumed search intelligent extraterrestrial civilization focusing candidate planets funding united_states_air_force newly discovered planets particularly ones potentially enabled programs projects communication extraterrestrial intelligence message earth sent system contains potentially planets confirmed unconfirmed project began human volunteers analyze data allen array search possible alien signals computers miss terrestrial radio interference data study obtained observing target stars radio addition radio based methods projects search extraterrestrial visible emissions nearby developed intelligent populations university california berkeley regions electromagnetic spectrum search extraterrestrial signals projects searching coherent signals want use electromagnetic radiation find evidence extraterrestrial intelligence projects signals wow signal detected history search extraterrestrial intelligence confirmed intelligent origin impact assessment implications extraterrestrial contact depend method discovery nature extraterrestrial beings location relative earth considering factors rio scale devised order provide picture results extraterrestrial contact specifically scale communication conducted radio information content messages discovery arose deliberately message detection result specialized effort general astronomical observations detection occurrences radiation installations question purported extraterrestrial signal confirmed authentic degree confidence influence impact contact rio scale modified include consideration contact achieved message physical extraterrestrial artifact suggestion definition artifact expanded include including indications intelligent extraterrestrial life radio messages sought traditional programs study dick united_states naval observatory considered cultural impact extraterrestrial contact analyzing events similar significance history science study argues impact strongly influenced information content message received distinguishes short term long term impact seeing radio based contact plausible scenario visit extraterrestrial spacecraft study rejects commonly stated analogy european colonization americas accurate model information contact preferring events profound scientific significance revolutions humanity impacted extraterrestrial contact physical distance assess cultural impact extraterrestrial contact historical examples greater distance contacted civilization threat culture contact occurring solar system especially immediate vicinity earth likely negative humanity smaller scale people close contact experience greater effect living farther away contact having multiple cause greater shock single space scientists martin john state absence data nature extraterrestrial intelligence predict cultural impact extraterrestrial contact basis encompassing life history beliefs general public effect extraterrestrial contact studied poll united_states chinese university students provides factor analysis responses questions inter participants belief extraterrestrial life exists universe life intelligent humans eventually contact study shows significant weighted participants belief extraterrestrial contact conflict personal religious beliefs conservative religious beliefs conservative respondents harmful considered extraterrestrial contact significant patterns indicate participants took view search extraterrestrial intelligence futile harmful post detection drawn detailing course action scientists governments extraterrestrial contact post detection address issues weeks receiving message extraterrestrial source send reply analyzing long term consequences message received post detection protocol binding national international law consider likely ignored contact occurs post detection declaration principles activities following detection extraterrestrial intelligence created permanent committee international academy later approved board trustees international institute space law later international astronomical union committee space research international union radio science subsequently endorsed researchers involved search extraterrestrial intelligence including institute declaration principles contains following broad provisions person organization detecting signal try verify likely intelligent origin announcing signal purposes independent communicate signatories declaration making public announcement inform national authorities given astronomical observation determined credible extraterrestrial signal astronomical community informed central bureau astronomical secretary general united_nations global scientific unions informed following confirmation observation extraterrestrial origin news discovery public right public announcement data confirming discovery published international scientific community stored accessible form permanently possible evidence extraterrestrial intelligence form electromagnetic signals secretary general international telecommunications union contacted request weekly circular minimize terrestrial use electromagnetic frequency bands signal detected respond observed extraterrestrial intelligence requires international agreement separate procedures permanent committee commission continually review procedures detection extraterrestrial intelligence management data related discoveries committee comprising members international scientific unions bodies designated committee regulate continued research separate proposed agreement sending communications extraterrestrial intelligence subsequently created proposes international commission membership open interested nations constituted detection extraterrestrial intelligence commission decide send message extraterrestrial intelligence determine contents message basis principles justice respect cultural diversity honesty respect property territory draft proposes sending message individual nation organization permission commission suggests detected intelligence poses danger human civilization united_nations security council authorize message extraterrestrial intelligence proposal like incorporated national international law paul davies member post detection stated post detection calling international consultation taking major steps detection unlikely followed advancement careers word protocol national international law contact scenarios considerations scientific literature science fiction forward models ways extraterrestrial human interact predictions range widely sophisticated advance human civilization areas imperial powers draw forces necessary humanity theories suggest extraterrestrial civilization advanced biology living instead inside advanced computers implications discovery depend level civilization interacting humanity ethics human extraterrestrial common factors govern quantity type dialogue place question contact physical electromagnetic signals govern magnitude long term implications contact case communication electromagnetic signals long silence reception message mean content message particularly affect consequences contact extent mutual friendly writers speculated ways friendly civilization interact albert harrison professor emeritus psychology university california davis thought highly advanced civilization teach humanity things physical theory use zero point energy travel faster light suggest collaboration civilization initially arts moving hard sciences artists collaboration global catastrophic risk institute consider greater longevity cooperative comparison aggressive ones render extraterrestrial general likely aid humanity contrast views member permanent study group international academy academy sciences took view extraterrestrial possess like humans morality driven entirely individual benefit leaving open possibility extraterrestrial hostile allen tough suggests extremely advanced extraterrestrial civilization recalling past war knowing possesses destroy likely try help humans destroy identifies approaches friendly civilization help humanity intervention involve occasional limited intervention stop events destroy human civilization completely nuclear war impact advice action consent approach closely involved terrestrial affairs advising world leaders acting consent protect danger action require humanity reduce major risks intending help humans advance stage civilization tough considers advising acting consent likely choice forceful option aid possible advanced recognize practices superior humanity unlikely method cultural cooperation suggests instruction civilization technological humanity probably focus morality ethics science technology ensure civilization destroy technology ready use according tough unlikely avoidance immediate dangers prevention future conducted radio tasks demand constant surveillance quick action cultural cooperation place radio space probe solar system radio waves communicate information advanced technologies cultures humanity ancient advanced extraterrestrial civilization wished help humanity humans suffer loss identity confidence technological cultural prowess extraterrestrial civilization friendly civilization contact humanity way minimize consequences michael suggests friendly advanced extraterrestrial civilization avoid contact emerging intelligent species like humanity ensure advanced civilization develop naturally pace hostile science fiction films depict humans successfully alien invasions scientists view extraterrestrial civilization sufficient power reach earth able destroy human civilization minimal effort operations enormous human scale destroying major population centers planet bombarding planet deadly radiation traveling system order lay waste important tools hostile civilization speculates small proportion intelligent life forms galaxy aggressive actual cover wide spectrum according harrison dick hostile extraterrestrial life rare universe nations earth ones lasted shortest periods time humanity seeing shift away characteristics systems addition causes war diminished greatly civilization access galaxy quantities natural resources space accessible resort violence researcher believed civilization technological prowess needed reach stars come earth war able avoid self destruction representatives civilization treat humanity dignity respect humanity relatively backward technology choice institute stating finite quantity resources galaxy aggression intelligent species explorer civilization want contact humanity aggressive similarly claims laws evolution planet earth extremely advanced extraterrestrial civilization motivation humanity british peoples australia analyses david states extraterrestrial civilization act benefit suggest trait prevalent galaxy points fact moral systems earth non military killing accepted society mentions acts confined humans found animal kingdom speculate highly advanced unlikely come earth humans achievement level advancement required solve problems labor resources means creating sustainable environment labor humans unsuitable food source marked differences example molecules terrestrial differ extraterrestrial beings politicians commented likely human reaction contact hostile species speech united_nations general_assembly ronald_reagan said occasionally think quickly differences worldwide facing alien threat outside world equally advanced advanced robert speculated technological advancement energy usage civilization measured relative civilization absolute terms rating scale play important role result extraterrestrial contact given space flight technological level similar humanity interactions place radio long transit times radio waves stars interactions lead establishment diplomatic relations significant future interaction according direct contact significantly advanced humanity place solar system advanced society resources technology cross space consequently contact rated type higher scale type incapable regular travel expected interactions carefully planned advanced civilization avoid mass societal shock humanity planning extraterrestrial civilization contacting humanity humans experience great shock terror arrival especially lack understanding contacting civilization ben compares situation new_guinea island settled thousand years ago glacial period saw little contact outside world arrival european colonial powers late 19th early 20th centuries huge difference indigenous stone age society europeans technical civilization caused unexpected behaviors native populations known cargo gods bringing technology europeans possessed natives created wooden radio stations form sympathetic magic argues humanity true meaning extraterrestrial transmission earth people new_guinea understand source modern goods technologies concludes results extraterrestrial contact known long term rigorous study fast sharp events briefly making newspaper headlines suggested civilization far advanced humanity likely culturally advanced unlikely conduct projects harm human civilization projects include spheres completely stars capture energy coming capability advanced civilization providing enormous energy project undertaken similar reasons readily humanity knowledge required build devices existence capabilities survived technological despite caution advanced civilization exercise dealing mature human civilization imagined advanced civilization send earth describing sciences cultures extraterrestrial societies advanced extraterrestrial civilization send humanity message matter debate argued highly advanced extraterrestrial civilization bear mind communicating relatively primitive try ensure receiving civilization able understand message arguing view stated advanced civilization probably message high information content order ensure advanced able understand groups given age galaxy harrison exist clubs multiple galaxy clubs begin loose alliances eventually developing powerful unions humanity enter dialogue extraterrestrial civilization able join club extraterrestrial unions thereof found club von suggested entry club way humanity handle culture shock arising contact advanced extraterrestrial civilization broad spectrum places galaxy able cooperate disputed states huge differences technologies resources command consider remotely equal unlikely humanity meet basic requirements membership current low level technological advancement club william hamilton speculates set extremely high entrance requirements unlikely met advanced suggests grouping form empire need necessarily force evil provide peace security jurisdiction owing distances stars empire necessarily maintain control solely military force tolerate local cultures institutions extent pose threat central imperial authority tolerance happened historically earth extend allowing nominal self rule specific regions existing institutions maintaining area puppet client state accomplish aims imperial power particularly advanced powers use methods including faster light travel centralized administration effective contrast belief extraterrestrial civilization want establish empire proposes extraterrestrial civilization maintain expand outward civilization small number stars aiming maximize efficiency expand massive imperial structures contrasts classic type iii civilization access energy output entire galaxy subject limits future expansion according view advanced resemble classic examples science fiction closely reflect small independent greek city states emphasis cultural territorial growth extraterrestrial artifacts extraterrestrial civilization choose communicate humanity means artifacts radio reasons long time reach solar system able hold sustained dialogue impossible radio hundreds thousands light years away radio completely unsuitable surveillance continued monitoring civilization extraterrestrial civilization wish perform activities humanity artifacts option send large spacecraft solar system faster light travel seriously considered tough speculates enormous energy required achieve speeds currently proposed mechanisms means robotic traveling conventional speeds advantage applications research nasa johnson space center shows faster light travel drive requires dramatically energy previously thought needing metric ton exotic mass energy spacecraft times speed light contrast previous estimates stated mass object contain sufficient energy power faster light spacecraft according tough extraterrestrial civilization want send types information humanity means artifacts containing wisdom countless extraterrestrial cultures invitation engage diplomacy civilization sees brink decline use abilities possesses send galaxy cultures values religions sciences technologies laws die civilization finds numerous reasons preferred method communication extraterrestrial wishing contact earth civilization aiming learn distribution life galaxy speculates send large number star systems radio ensure response radio says ensure return data star systems survey furthermore enable surveying non intelligent populations capable space navigation like humans 20th century intelligent populations wish provide information planets extraterrestrial addition greater energy required send living beings robotic probe according purposes way migration points unlike radio waves commonly targeted searches store information long geological strong radio signals recognizable intelligent origin dismissed ufo natural phenomenon modify signal send suit system impossible radio transmission originating outside target star system use small robotic widely distributed individual systems small number powerful centralized provide security advantage civilization revealing location radio beacon powerful signal galaxy risk powerful device compromised installed robotic need reveal information extraterrestrial civilization prefers given age way galaxy ancient extraterrestrial civilization existed sent solar system millions years evolution probe sent millions years humans learn existence dead probe pose imminent threat humanity prove flight possible active probe discovered humans react strongly discovery probe long ceased function implications contact theological confirmation extraterrestrial intelligence profound impact religious doctrines potentially causing scriptures accommodate new discoveries survey people different religious beliefs indicated faith affected discovery extraterrestrial intelligence study conducted pacific lutheran theological seminary shows people consider religious beliefs superseded surveys religious leaders indicate small percentage concerned existence extraterrestrial intelligence fundamentally views adherents religion chief vatican observatory papal adviser science stated catholic_church likely welcome extraterrestrial visitors warmly contact extraterrestrial intelligence completely religion study showed non religious people significant majority religious people believe world face religious crisis beliefs unaffected contact extraterrestrial intelligence likely cause problem western religions particular christianity nature western discovery extraterrestrial life basic god seeing science challenged established past example theory evolution teachings likely existing religions adapt similarly new circumstances view global religious crisis unlikely studies christianity religion conflict religion existence extraterrestrial intelligence addition cultural religious values extraterrestrial species likely shared centuries contact occur radio meaning causing huge shock humanity information viewed archaeologists historians view ancient artifacts texts speculates message extraterrestrial intelligence initiate exchange knowledge disciplines including religions extraterrestrial civilization host suggests extremely advanced friendly extraterrestrial civilization end present day religious conflicts lead greater religious worldwide hand puts forward view contact extraterrestrial intelligence eliminate religion know introduce humanity encompassing faith political tim speculates news radio contact extraterrestrial civilization prove impossible suppress travel rapidly cold war scientific literature subject media coverage discovery probably die quickly scientists began message learn true impact different branches government example legislative executive judiciary pursue policies potentially giving rise power struggles event single contact follow radio contact prompt fierce disagreements bodies authority represent humanity fear arising direct contact cause nation states aside conflicts work common defense humanity apart question represent earth contact create international problems degree involvement governments foreign radio received signal united_nations discussed issues foreign relations immediately launch voyager left solar system carrying golden record case found extraterrestrial intelligence issues discussed messages best represent humanity format convey cultural history earth international groups formed study extraterrestrial intelligence greater detail according university genoa contact powerful extraterrestrial civilization comparable occasions powerful civilization destroyed arrival christopher columbus americas subsequent destruction indigenous ways life model contact extraterrestrial specific interpretation arrival european colonists americas disputed large difference power extraterrestrial civilization potentially cause accelerate collapse human society discovered superior extraterrestrial civilization continued contact psychological effects destroy civilization claimed happened past earth absence close contact humanity high information messages extraterrestrial civilization humanity potential cause great cultural shock knowledge extraterrestrial culture theology potential compromise human allegiance existing organizational structures institutions cultural shock meeting extraterrestrial civilization spread decades centuries extraterrestrial message humanity extremely difficult legal contact extraterrestrial raise legal questions rights extraterrestrial beings extraterrestrial arriving earth protection animal cruelty statutes classes human women children indigenous people initially denied human rights extraterrestrial beings legally owned killed species treated legal animal arise challenge defining boundary legal person legal animal considering numerous factors constitute intelligence considers extraterrestrial afforded legal problems immigration arise extraterrestrial legally recognized citizenship drastic legal measures required order account technically illegal immigration extraterrestrial individuals contact place electromagnetic signals issues arise issues relating patent copyright law rights information extraterrestrial civilization primary legal problem scientific technological scientific technological impact extraterrestrial contact electromagnetic waves probably small especially message contains large information humans access heritage human species greatly advance technology science possible negative effect research scientists come know researching known civilization hand extraterrestrial intent send information enable human civilization destroy powerful computer information extremely potent weapons humans able use motives action unknown require minimal energy use according computer particular nearly impossible possess detailed knowledge human computer happen human message sent stars protected little thought security virtual machine run computer programs designed specifically purpose bearing little relation computer systems commonly earth addition humans send messages detailing want access reached suitable level technological advancement harmful impacts extraterrestrial technology extraterrestrial technology profound impacts nature human culture civilization television provided new outlet wide variety political religious social groups printing press bible available common people europe allowing interpret extraterrestrial technology change humanity ways immediately apparent harrison speculates knowledge extraterrestrial technologies increase gap scientific cultural progress leading societal shock inability compensate negative effects technology gives example improvements agricultural technology industrial revolution displaced thousands farm laborers society jobs suited new social order contact extraterrestrial civilization far advanced humanity cause greater shock industrial revolution previously experienced humanity suggests humanity impacted influx extraterrestrial science technology way medieval european scholars impacted knowledge arab scientists humanity knowledge having potential advance human species feel inferior extraterrestrial species gradually grow arrogance gained intimate knowledge science technology cultural developments advanced extraterrestrial civilization discovery extraterrestrial intelligence impacts biology discovery extraterrestrial life form intelligent non intelligent humanity greater insight nature life earth improve conception tree life organized human learn extraterrestrial observe differs found earth knowledge help human civilization learn aspects life common universe specific earth ecological biological warfare impacts extraterrestrial civilization bring earth invasive life forms harm alien human population immunity use terrestrial livestock plants hosts causing indirect harm humans invasive organisms brought extraterrestrial cause great ecological harm terrestrial lack defenses hand invasive species extraterrestrial origin differ terrestrial organisms biology adverse effects furthermore parasites earth generally suited small exclusive set environments extraterrestrial opportunity adapt extraterrestrial civilization bearing humanity gained sufficient knowledge terrestrial biology weaknesses immune systems terrestrial able create extremely potent biological weapons civilization intent inadvertently cause harm humanity taking account risks actions according extraterrestrial civilization communicate electromagnetic signals send humanity information humans create lethal biological weapons

Potential cultural impact of extraterrestrial contact


type naturally occurring source stimulated line distinguished large typical solar million times brighter way prefix mega likewise term describe outside way order thousands times stronger average way describe times stronger average way encompasses found outside way known majority meaning line transition known molecules water water type discovered water found galaxy nearby group found nearest infrared galaxy way subsequent discovered infrared small number hosted lower infrared infrared recently merged interacted galaxy undergoing burst star formation characteristics distinct way including background radiation ratio lines different frequencies population molecules produced far infrared radiation results absorption light forming stars surrounding dust splitting lines measure magnetic fields regions application represents detection splitting galaxy way water found primarily associated active weaker water found star forming regions despite different environments circumstances produce water different produce water observations water accurate measurements distances order provide constraints constant background word derives acronym stands microwave stimulated radiation predecessor operate optical named replacement microwave light given system molecules different energy states absorb higher energy level stimulate energy cause transition lower energy level producing requires population system members higher energy level relative lower energy level situation produced stimulated absorbed system thermal requires special conditions occur specifically energy source pump molecules excited state population occurs energy corresponding energy difference states produce stimulated energy drop lower energy level energy repetition process leads energy light produced built earth occur space require population order operate conditions population occurs different cases laboratories systems high limits transitions requires cavity order bounce light forth times low naturally long path lengths low thermal easily achieved thermal maintained collisions meaning population occur long path lengths provide traveling medium opportunities stimulate produce background source radiation factors accumulate space natural environment operation pumped pumping infrared higher energies transition molecules upper state order produce population pumping population instead produced collisions molecules energy levels upper level upper level history years built laboratory discovered plane way molecules discovered way following years including water typical evidence detection roughly times discovered infrared galaxy source assuming roughly roughly million times stronger typical found way source called time water known water discovered comparable strength considered water decade discovered relatively rare known hand common way types found detected seen absorption found absorption sources known formula water known bright considered general requirements regardless requirements met strong source exist requirement radio background source provide radiation transitions place radio pumping mechanism create population sufficient density path length significant place combine given place specific conditions known produce different exemplified fact known galaxy hosts common species water different molecules known addressed individually hosts discovered nearest infrared galaxy studied great detail reason prototype host guide interpreting hosts hosts environment found nuclear region class called infrared far infrared excess billion solar ultra infrared favored infrared large cases particularly visible light instance ratio infrared blue light roughly source observed majority evidence interaction having recently experienced galaxy merger holds true host hosts rich molecular gas compared spiral molecular hydrogen masses excess billion solar masses help funnel molecular gas nuclear region producing high molecular high star formation rates characteristic turn heats dust far infrared produces high observed hosts dust temperatures derived far infrared warm relative ranging far infrared dust temperature affect likelihood hosting dust temperature far infrared unclear observations role producing warmer dust likely host hosts compared roughly early observations indicated far infrared formula discovered care taken account bias observed relationship found formula formula early classification host indicated properties host distinguished overall population roughly hosts classified quarter classified remainder classified low nuclear line regions liners optical properties hosts non hosts significantly different recent infrared observations space able distinguish hosts non hosts evidence active nucleus compared non host distinguished general population molecular gas content majority molecular gas molecular hydrogen typical hosts molecular gas greater highest mean molecular gas host high dense gas relative typical dense gas fraction measured ratio produced hydrogen relative carbon line characteristics occurs predominantly called main lines satellite lines satellite lines detected known stronger line typical line line called ratio range minimum greater ratio range depending optical depth line greater indicative population thermal compared star forming regions line typically strongest evolved stars line strongest main lines frequently stronger total width given frequency typically hundreds kilometers second individual features total profile ranging tens hundreds kilometers second compared typically order kilometer second narrower spread velocity tens kilometers second radiation radio host primarily composed radiation produced type background low factors gains ranging percent percent sources larger typically exhibiting larger gains sources higher gains typically narrower lines expected pre gain roughly line centers wings leading line including observed long allows sources studied higher angular resolution observations indicate composed components compact component displays gains factor order hundreds kilometers second characteristics similar seen single dish observations unable resolve individual components compact components high gains ranging tens hundreds high order kilometers second general features explained narrow ring material arises individual clouds sizes order rise compact observed way closely resemble compact components regions extended molecules resemble component pumping mechanism observed relationship line far infrared suggests pumped initial measurements nearby present problem model compact components required high fraction infrared absorbed lead emitted making plausible pumping mechanism model medium appear able reproduce observed properties compact recent detailed treatment finds primary pump main line applies order provide dust stellar radiation infrared temperature recent observations space confirm basic picture details model observations host required dust applications occur nuclear regions appear marker stage formation subject extinction dust host useful conditions star formation takes place like ones nearby universe observed relationship far infrared suggests tens hundreds times observed detection allow precise determination aid understanding star formation objects detection effect galaxy observations effect splitting line presence magnetic field size splitting proportional line sight magnetic field strength splitting detected typical strength detected field order similar field strengths measured water fundamentally distinct ways water require conditions water water stronger water strong classified mega described function water water occur star forming regions like water stronger water found regions active span range order found nearby like distant like line characteristics pumping mechanism water observed primarily transition energy levels water upper state energy corresponding ground state upper level requires number molecular hydrogen order greater temperatures water comes thermal molecular hydrogen number roughly places upper limit number density water region water successfully modeling occurring shock waves dense regions medium produce high number temperatures relative typical conditions medium required successful explaining observed applications water provide accurate distance distant assuming orbit measuring acceleration velocity water spots yields physical diameter spots comparing physical radius angular diameter measured sky distance determined method effective water occur small region narrow method measuring distances provide independent measure constant rely use standard candles method limited small number water known distances flow distance measurement provides measurement mass central object case black hole black hole mass measurements water accurate method mass determination black holes way black hole masses measured consistent relation stellar velocity mass central black hole


controversy discovery current recognized dwarf planets discovered naming formal acceptance dwarf planet delayed years controversy receive credit discovering california institute technology team headed michael brown noticed object spanish team headed announce normally receive credit brown suspects spanish team fraud observations discovery team accuses american team political interference international astronomical union officially recognized team proposed proposed spanish team september discovery announcement december mike brown team discovered images taken observatory united_states looking hoped tenth planet discovery team nickname santa discovered december christmas clearly small planet significantly smaller brown announce discovery instead kept large trans objects pending additional observation better determine team discovered realized rocky ice discovered small family nearby concluded remnants mantle collision july finishing paper describing discovery brown daughter born delayed announcement july team published online abstract report intended announce discovery conference following september given code time student sierra nevada observatory southern spain claims examined photos team started taking december says found late july images taken march said checking known object team came brown internet summary describing bright like found reference number object morning july found observation logs according account logs contained little information tell object team checked minor planet center record object wanting establish priority discovery night july titled big discovery urgent making mention logs morning accessed logs including observations additional nights asked amateur astronomical observatory observations found images observatory located night july hour team submitted second report included new data mention having accessed logs data published july press release day team called tenth planet july given official label temporary designation based date spanish discovery image september numbered admitted official minor planet catalogue reaction announcement day publication brown group announced discovery belt object distant brighter apparently larger tenth planet announcement earlier planned possibility similar events discovery told data publicly accessible realized data time data publicly accessed day announced discovery brown submitted draft data discovered january journal brown disappointed congratulated team discovery apologized immediately announcement announcement explained accessed data afraid volunteer accessed data learning web records computer sierra nevada observatory accessed observation logs day discovery announcement logs included information allow team images brown came suspect fraud august asked explanation respond august team filed formal complaint accusing team breach scientific ethics failing acknowledge use data asked strip discovery status later admitted accessed observation logs denied wrongdoing stating merely discovered new object brown began wonder spanish team actually identified saw abstract log official naming protocol discovery credit minor planet goes report data decent orbit determination credited priority naming proposed goddess underworld equivalent roman goddess turn lovers deity appropriate object resonance neptune following guidelines established classical belt objects given names mythological beings associated creation september team submitted formal names hawaiian mythology order pay homage place satellites discovered names proposed david team goddess island observatory located addition identified goddess earth wife space appropriate thought composed entirely solid rock thick ice mantle small rocky core typical known belt objects lastly goddess fertility children sprang different parts body corresponds bodies thought broken dwarf planet ancient collision known believed born manner named daughters dispute actually discovered object delayed acceptance formal classification object dwarf planet september announced bodies charge naming dwarf planets committee small body nomenclature working group system nomenclature decided proposal outcome voting close eventually decided single vote date discovery listed announcement march location discovery sierra nevada observatory left blank aftermath brian head harvard supported brown claim saying sooner later realise happened mike brown credit went state reference left blank listing deliberately vague object don want cause international incident called controversy worst early 17th century dispute found biggest satellites simon ultimately won team objected suggesting accepted chosen favoring party accusing political bias rumors appeared god irish mythology neutral proposed member end went happy think decision unfortunate sets bad precedent spanish newspaper abc went decision conquest asserting politics played major role times scientists spain immediately announcement brown noted unusual allowed object acknowledged official declared pleased outcome think good resolution recognition discovery fifth anniversary discovery wrote blog thoughts importance discovery mention events controversy

Controversy over the discovery of Haumea


radio bank observatory near north west england construction finished largest dish radio world diameter largest green bank west_virginia usa germany originally known radio bank mark future mark iii discussed renamed sir bernard grade listed building forms european network radio bernard charles husband roles creating september won bbc online competition find greatest landmark marked 50th anniversary air clear mark seen high rise buildings manchester tower far away winter hill lancashire castle peak district seen terminal restaurant area departure manchester airport construction conception construction mark bernard built transit bank late 1940s radio point directly upwards logical step build look parts sky sources observed longer integration times transit designed constructed fully need professionally designed constructed challenge find engineer willing job turned charles husband met september bearing assemblies inch gun turrets bought came world war battleships hms revenge royal sovereign broken time main altitude appropriate parts designed husband presented drawings proposed giant fully radio plans detailed blue book presented march proposal approved march construction began september foundations completed sunk ground took mid march double railway lines completed required accuracy central pivot delivered site final mid april bowl originally going wire surface observe meters feet changed steel surface observe hydrogen line discovered february air ministry met funding available improving accuracy dish research ministry purposes funding ultimately available air ministry planning process progressed far improvement constructed bowl completely inverted originally intended use tower base change receivers focus tower built jointly funding constraints fact receiver equipment placed base focus instead receivers mounted foot long steel tubes inserted aerial tower bowl inverted cables receivers ran inside tube connected pointed associated receiver equipment placed small swinging laboratory directly underneath surface rooms tops towers base control building moved time february inch moved power june bowl power time june end july dish surface completed light august drift scan way bowl controlled control room october purpose built computer large cost construction mainly rising cost steel time constructed original grant construction came jointly foundation government amounted government increased share funding times cost rose money came private donations final debt construction paid lord foundation partly early public role space probe tracking bank observatory renamed radio astronomy laboratories final total cost upgrade mark shortly originally completed husband started contemplating idea upgrading accurate surface controlled digital computer plans upgrade created husband presented april plans urgent fatigue cracks discovered elevation drive system september expected operational lifespan years husband warning decay appearance fatigue cracks problems threatened stop working left place elevation system failed jammed repaired upgraded mark funding announced july upgrade repair mark upgrade carried phases phase lasting september february phase september november phase august november phase saw addition inner railway track designed weight outer railway track decaying sinking previous years second phase added inner track existing outer track overhauled phase saw biggest changes new accurate bowl surface constructed old surface meaning small central bicycle wheel support added new computer control system place computer mark fatigue cracks connecting bowl towers repaired central antenna lengthened strengthened january holding engineers central antenna snapped causing grave injuries engineers resulting death mark upgrade formally completed july handed university manchester increases cost steel upgrade final upgrade later upgrades repairs gale january january brought winds mph destroyed towers connecting dish towers slipped expensive repair diagonal added towers prevent happening 1990s surface badly resurfaced increasing sensitivity factor technique surface meaning surface works compared old surface new drive system installed provides higher pointing accuracy outer track focal tower strengthened support heavier receivers needed new drive wheel original wheels cracked new steel tyre needed second wheel cracked wheel changes needed started operation presence breeding pairs wild nesting support towers prevents body heat affecting sensitive instrument readings radio suffer statistics space probe tracking artificial satellites operational summer time launch world artificial satellite easily picked household radio capable tracking rocket radar located midnight october located carrier rocket midnight november took early work satellite communication february march transmitted signals moon echo nasa balloon satellite altitude observatory ussr signals relayed usa ussr bank race moon track soviet american aimed moon late 1950s early 1960s terms american space tracked pioneer november pioneer december pioneer march tracked pioneer march june send commands probe including separate probe carrier rocket ones turn powerful probe million miles million away received data pioneer world capable time signal picked probe distance million kilometers june tracked soviet moon including september hit moon proven measuring effect moon gravity probe october tracked february spacecraft soft landing moon listened transmission photographs moon surface photos sent british press probe transmitted likely intentionally increase chances reception international format image transmission published soviets photos public tracked russian satellite orbit moon april september russian probe launched moon returning earth track apollo tracking july bank time track apollo venus possibly detected signals russian satellite route venus possible confirm origin signals years later december tracked received data october received signals tracked russian probe venus mars tracked mars mars mars amidst upgrade mark recent years searched lost mars spacecraft including nasa mars observer spacecraft mars polar mars succeed locating measure raf built standby project verify known april september strategic pulse receiver display equipment connected scan known russian launch sites indications launches cuban missile crisis october turned iron curtain provide minute warning missiles launched scientific observations proposed series objectives observations set included surveys radio observations sun radar echoes planets investigation observations studies aurora radio reflections cosmic ray atmosphere actual observations differ original objectives outlined following sections solar system autumn bounce moon demonstration lecture receive messages bounced moon 50th anniversary festival april radar echo venus achieved planet close approach confirming measurements distance planet american hydrogen line hydrogen line discovered construction subsequently redesigned observe frequency line hydrogen clouds way galaxy observed example discovered large cloud motion clouds away line allowing velocity cloud measured provides probe internal dynamics provide measurement rate expansion universe discovered emissions star forming regions giant stars astronomical frequencies easily regularly construct maps regions observed coordinates recently discovered confirming existence investigating measure detection radiation marked start substantial work investigating ongoing years following discovery discovered new bank discovered total number regularly observed nearby foot dish involved discovery discovered cluster cluster september results years observing double green bank announced confirming general theory accurate detailed survey radio sources limited area sky sensitivity limit instrument objects lens confirmed position found coincide pair faint blue stars mark mark involved detection ring conjunction observations space early investigation size nature drove development techniques 1950s advantage large collecting area meaning high sensitivity measurements relatively quickly result featured heavily discovery bank started constructed transit square meter broadside array determine size radio loud construction complete broadside array mount pair tracking radio determine shape sky summer foot diameter constructed aluminium mounted rotating structure old defence radar mark resolution determine sizes high mark constructed meaning diameter giving resolution pair carry survey work determine positions faint radio objects drivers construction mark iii use mark carry survey radio sources took experiment canada radio new array series smaller radio controlled bank gave resolution upgraded version national facility long europe european network giving resolution half observing time spent planned work russian space observatory programme japanese radio satellites providing larger higher resolutions notable observations follow instrument possible end signals detected february discovered galaxy appears entirely dark matter popular culture scale model resides science museum london mentioned sci novel fred john doctor episode filmed park model project doctor played tom baker fell model based mark featured modifications mark rim edge dish actress portrayed seventh doctor companion ace standing superstructure dish doctor educational special search science search space featured cover sub sub space face single brief appearance film version guide galaxy bands shot music videos bowl party world bitter end public service broadcasting long shots feature music video secret messages royal mail depicted bank landmarks stamp series previously featured stamps haiti hungary ascension island books bernard story bank oxford_university press isbn bernard bank oxford_university press isbn bernard bank oxford_university press isbn bernard chance london isbn roger story bank london isbn journal articles bernard bank radio nature high resolution observations tracking radio august science technology cold war military uses bank radio cold war history