abbreviated named closely sun like host star mass earth masses diameter twice earth classifying super earth discovered main sequence star year takes fewer hours complete orbit known planet system discovered august observations planet thought days orbit star october announced carbon planet july international astronomical union launched process giving proper names certain host stars process involved public nomination voting new names december announced winning planet winning submitted royal netherlands association astronomy netherlands honors spectacle maker pioneer february announced nasa space detected hydrogen suggestions hydrogen water atmosphere time atmosphere super earth analyzed successfully discovery like majority planets found prior mission discovered detecting variations star radial velocity achieved making sensitive measurements shift spectrum time discovery planets known star accounting planets signal days remained explained planet earth masses close orbit measurements confirm existence uncertain planet planets mass comparable neptune discovered announced time hot neptune red dwarf star named planet challenged existence planet questioned jack wisdom data according instead day planet planet mass similar neptune day orbit fischer colleagues san_francisco state university published new analysis indicating planets existed planet day orbit accordingly designated transit planet transit primary announced april based weeks nearly continuous monitoring space occur period days phase predicted confirmed known star allowed investigations planet composition orbit mass radial velocity method detect minimum mass times earth mass neptune transit shows real mass close minimum characteristics receives radiation planet facing star temperatures approximately degrees hot melt metal initially unknown small gas giant like neptune large rocky terrestrial planet transit planet confirmed allowing scientists density suspected water planet initial observations showed hydrogen alpha signature transit speculated volatile materials carbon dioxide instead water hydrogen alternative possibility solid planet carbon rich material oxygen rich material makes terrestrial planets solar system case roughly planet mass carbon form diamond result temperatures pressures planet interior observations necessary confirm nature planet february announced nasa space detected hydrogen suggestions hydrogen water atmosphere time atmosphere super earth analyzed successfully large surface temperature variations attributed possible volcanic activity releasing large clouds dust blanket planet block thermal emissions


located degrees sky away discovered derived word right ascension located indicating coordinates discovered don michael davis miller discovered period meaning completes second period far shorter considered capable reaching led suggestion spun mass companion rotation discovered later stable rotation capable keeping time atomic unusual occasionally particularly strong density giant emitted radio observed properties unexpected discovery credited helping research background discovered bell phd supervisor array shortly discovery franco thomas gold independently suggested highly rotating stars form result end life stars massive times mass sun radiation emitted caused interaction surrounding star rapidly rotating magnetic field interaction leads pattern rotating beacon escapes magnetic poles star rotating beacon property arises magnetic poles poles discovery late 1970s radio source captured attention radio high level associated compact radio sources observations suggested remnant survey carried observatory russell joseph taylor region discover associated lack success finding region explanations explored including suggestion entirely new classes objects realizing previous searches region sensitive periods short produce observed don initiated search area sensitive wide range pulse periods measures including short periods initial search plan sample rate fast detect spinning search apparatus student sampled quickly possible time averaged signal period effectively sampling result determined november source rotating rate far studying expected characteristics age spin rate reported finding november found rotation period decreasing rate seconds second expected slow time energy ultimately drawn energy initially observed values period spin rate assuming minimum period maximum age found years old estimate minimum possible period obtained break limit period force self gravity equal value minimum period depends star equation state different models giving values corresponds rotation frequency mechanisms radiation reaching absolute limit spin faster age years odds observations region optical remnant bright ray source observed vicinity young time far site formed stars formed result explosions evidence explosion nearby young young expected hot case thermal radiation ray lack observed remnant argue formed fast period instead spun companion star essentially gave angular momentum mechanism generally explain theoretical estimate necessary spin rate seconds second revised estimate upper limit spin rate month initial discovery seconds second currently measured value nearly line theoretical estimate seconds second age later determined years value consistent evidence companion supposed spun longer present making stellar mass companion generally high occurrence companions expected considering companion necessary spin short periods actively matter companion instead need time past lack companion seen disagreement spin model possible mechanisms creating isolated include donor star tidal disruption system period rotation peaks observed known pulse unusual occasionally produces far brighter average pulse sole known produce giant crab observed produce giant known giant observed shortly discovery difficulty observing single fast period meant studied depth decade observed recent follow observations giant found giant observed occur trailing edge pulse duration giant short compared period lasting order density observed somewhat variable observed high temperature pulse high density low duration exceeds making radio observed addition radio observed detected ray pulse pattern evidence companions discovery mass companions data analyzed presence similar companions upper limit mass earth determined companion astronomical units reported variations times arrival previous analysis suggested timing variations caused dwarf planet data consistent companion having mass similar located astronomical units data longer period time required order verify proposed companion recent observations detected regular periodic signal associated companion argue slight variations pulse arrival times consistent belt having total mass earth acknowledge detection pulse timing variations associated individual necessary confirm possible belt significance discovery spins times second fastest spinning star known remains second fastest spinning known addition extending range periods observed factor extended range magnetic fields observed factor magnetic field discovered sparked theory providing new laboratory study stars generally problems waves instance density required spin high rates comparable nuclear fastest spinning important understanding matter initially high estimate spin rate intriguing implied signal directly detected wave actual spin rate expected signal sensitivity current currently accepted value spin rate corresponds change period course million years stability rotation order stability best atomic tool establishing time discovery launched extensive surveys major radio happened astronomy time people thought field


star located light years away field view mission nasa operation finding earth like planets neptune sized planet extremely close star discovered orbit public team january discovery satellite confirmation helped demonstrate spacecraft effectiveness nomenclature history named spacecraft nasa tasked finding earth like planets transit stars seen earth previous planets confirmed confirmed finds planet discovered team star system announced washington meeting american astronomical society january presented planets smallest size planet neptune discovery planets presented meeting helped confirm spacecraft functional smith mcdonald observatory fort davis texas university texas austin follow discoveries confirm hawaii california arizona islands confirm findings characteristics type star similar sun slightly brighter star mass radius sun metal rich sun figure important metal rich stars tend planets metal poor stars billion years old comparison sun billion years old addition effective temperature identical errors sun seen earth apparent magnitude result visible naked eye system discovery announced january size planet neptune mass radius planet star days star distance compares planet mercury sun assumed subsequent independent discovery data found value likewise temperature planet assumed far assumed considering internal heat atmosphere


astronomy seven sisters open star cluster containing middle aged hot type stars located nearest star clusters earth cluster obvious naked eye night sky entity meanings different cultures traditions cluster dominated hot blue extremely stars formed million years dust forms faint reflection stars thought left formation cluster alternative star known unrelated dust cloud medium stars currently passing computer shown probably formed compact configuration resembled estimate cluster survive million years disperse interactions neighborhood origin comes ancient greek probably derives sail cluster importance sailing season mediterranean_sea season navigation began rising later seven divine sisters imagined derive mother effectively meaning daughters reality star cluster certainly came invented explain history prominent sight winter northern hemisphere known antiquity cultures world including australians arabs called chinese japanese maya known associated war god derives god raised sisters known said developed face star star stars head list stars reflecting fact close point 23rd century ancient names followers texts calendar lucky days cairo earliest known depiction likely bronze age artifact known sky disk dated approximately greek considered distinct mentioned homer odyssey mentioned times bible job scholars islam suggested star mentioned chapter persian equivalent pronounced japan mentioned stars 8th century documents known japan unite chosen brand automobiles reflect origins firm joining companies depicted firm star logo rising mentioned ancient greek text greeks oriented temple rising rising dawn usually beginning june long regarded start new year culture star group known rising celebrated festival new_zealand hawaiian culture cluster known rising shortly sunset marks beginning month time peace honor god view discovered cluster contains stars dim seen naked eye published observations including sketch showing stars treatise march long known physically related group stars chance alignment reverend john calculated probability chance alignment bright stars correctly clusters stars physically related studies stars proper motions found moving direction sky rate demonstrating related charles measured position cluster included catalogue like objects published cluster inclusion noted curious objects easily confused scarcely possible possibility simply wanted larger catalogue scientific rival catalogue contained objects added bright known objects boost list drew map stars observations published distance distance important step cosmic distance ladder cluster close earth distance relatively easy measure estimated methods accurate knowledge distance allows plot russell cluster compared plotted clusters distance known allows distances estimated methods extend distance scale open clusters clusters cosmic distance ladder constructed ultimately understanding age future evolution universe influenced knowledge distance authors argue controversy distance discussed red herring cosmic distance ladder presently rely suite nearby clusters consensus exists distances established independent means coma cluster etc measurements distance controversy results prior launch satellite generally found away earth data yielded surprising result distance measuring stars cluster technique yield direct accurate results later work consistently argued distance measurement erroneous particular distances derived cluster space infrared color magnitude fitting favor distance distance optical observations double favors distance author catalog revised distance challenged evidence recently francis anderson proposed systematic effect errors stars clusters calculation weighted mean gave distance distance based stars beta moving groups similar age composition authors note difference results attributed random error latest result august long radio determine distance claiming measured distance cluster error composition cluster core radius light years tidal radius light years cluster contains confirmed members figure unresolved stars dominated young hot blue stars seen naked eye depending local observing conditions arrangement stars somewhat similar major minor total mass contained cluster estimated solar masses cluster contains brown objects sun mass heavy nuclear fusion reactions start proper stars constitute total population cluster contribute total mass great efforts find brown young clusters relatively bright brown older clusters faded difficult study age future evolution ages star clusters estimated comparing russell cluster theoretical models stellar evolution technique ages million years estimated wide spread estimated ages result stellar evolution models include factors convective convective zone star non convective zone resulting higher apparent ages way estimating age cluster looking lowest mass objects normal main sequence stars rapidly destroyed nuclear fusion reactions brown retain low temperature million highest mass brown burn eventually determining highest mass brown containing cluster idea age applying technique gives age million years cluster slowly moving direction feet currently like open clusters stay bound forever component stars ejected close encounters stars stripped tidal fields calculations suggest cluster million years disperse interactions giant molecular clouds spiral arms galaxy demise reflection ideal observing conditions hint seen cluster shows long exposure photographs reflection caused dust reflecting blue light hot young stars thought dust left formation cluster age million years generally accepted cluster dust originally present dispersed radiation pressure instead cluster simply passing particularly dusty region medium studies dust responsible uniformly distributed concentrated mainly layers line sight cluster layers formed radiation pressure dust moved stars stars stars named seven sisters greek mythology parents daughters sisters english cluster greek origin uncertain etymology suggested include sail making sailing ones flock following table gives details stars cluster list possible planets analyzing deep infrared images obtained space north discovered cluster stars mass bit greater sun surrounded extraordinary number hot dust particles evidence planet formation


known sun like star lies light years earth targeted nasa spacecraft seen star identified mission possible host small star slightly massive slightly larger slightly cooler sun estimated billion years age times age sun host system planets undeniably rocky planet discovered orbit months observation announced january planet star closely completing orbit days density similar iron second planet confirmed based follow observations space data shows period days radius double earth higher density making largest massive rocky planet discovered june nomenclature history named tenth system observed spacecraft nasa satellite designed search earth like planets transit cross host stars respect earth transit slightly host star periodic effect noted months observation ranging january team established rocky discovered satellite targeted star suspected having small planet orbit discovery observatory hawaii discovery successfully verified potentially rocky discovered past definitively rocky planet discovered discovery announced public winter meeting american astronomical society january seattle existence confirmed meeting boston characteristics type star like sun mass radius star approximately smaller wider sun measured iron star means metal rich sun tends play large role formation planets determining form kind planet form addition estimated billion years old effective temperature compare sun younger age billion years effective temperature located distance earth approximately light years apparent magnitude seen earth seen naked eye system usual nomenclature planet discovered called announced rocky planet identified outside solar system planet mass times earth radius times earth planet distance days compared orbit period planet mercury circles sun distance days planet closely star virtually zero extremely circular orbit discovered nasa mission second found orbit radial velocity measurements body suggest mass earth masses radius earth making largest known rocky planet orbit distance days


star discovery announced august planet discovered orbit meaning direction counter rotation host star discovery challenged traditional formation theory terms diameter second largest discovered half mass makes planet known december scientists working space reported detecting water atmosphere discovery team researchers led david anderson university england discovered gas giant light years earth observing transit host star observations reveal planet size discovery array south african astronomical observatory involvement wide angle search planets consortium universities 17th found date group given present observatory geneva able use characteristic red shifts blue shifts host star spectrum radial velocity varied course planet orbit measure planet mass obtain indication careful examination shifts allowed determine direction planet motion relative parent star rotation effect special properties radius times half mass mean density compared earth density water unusually low density thought consequence combination planet proximity parent star seventh distance mercury sun leading tidal heating interior mechanism intense volcanic activity moon thought orbit sky projected orbit normal stellar spin axis confused line sight orbit given table near planets planet discovered motion found measuring effect planet star signal star turning away earth slight planet scientists sure planet opposite star rotation theories include resulting near collision planet intervention smaller planet like body working gradually change orbit mechanism


hip hip object planet brown dwarf orbit star hip observed early object confirmed orbit star hip direct imaging project photographed star image caught attention project science team team followed initial observations hip young hot bright blue star upper association planet times massive eighteen times host star sun estimates published discovery paper predicted orbit hip completes orbit thousand years discovery system chile detected faint object vicinity hip object reported investigating star able tell based observations faint object companion team follow random selection ninety stars upper association provided sample stars observed near infrared altitude infrared system observatory ninety stars selected direct imaging star hip camera initial image revealed presence faint object vicinity hip follow imaging took place july august instruments hoped reveal companion object proper motion rate moves time additional follow data recovered spring summer large errors data led investigating disregard observations years compiled data filter portions images improve images quality result suggested faint object image nearby star hip brown dwarf planet size study needed prove true nature july july august use integral field allowed collect data spectrum faint object star analysis objects star faint object change position sky led confirmation companion hip confirmation hip reported january imaging ninety stars hip discovered discoveries bodies allowed predict bodies low planet brown dwarf star mass distance hundreds exists stars number lower limit unable detect smaller low mass planets fit scenario host star hip bright blue type main sequence star upper association loose star cluster composed stars common origin star estimated approximately times mass sun ages upper group quoted million years recent estimate suggests group somewhat older approximately million years old effective temperature estimated twice effective temperature sun hip apparent magnitude incredibly faint visible seen eye observer earth characteristics hip likely brown dwarf massive object large fuse planets small large star hip characteristics blend line brown dwarf planet tried determine hip predicting created planet like star like brown formed manner estimated mass times additionally hip host star estimated average distance times average distance earth sun assuming brown dwarf circular orbit average distance dwarf planet sun meaning hip host star nearly eighteen times sun accordance data hip complete orbit approximately years actual motion hip likely smaller directly observed long know definitively


alpha alpha alpha traditional names arabic word star located immediately northeast northeastern star great square considered alpha shared assigned designation alpha delta modern boundaries fixed designation dropped use located light years earth appears naked eye single star overall apparent visual magnitude actually system composed stars close orbit chemical composition brighter stars unusual mercury star atmosphere contains high levels mercury elements including mercury star known system radial velocity star away observer determined measuring red shift blue shift spectrum american series measurements discovered radial velocity varied periodically concluded orbit star system period days preliminary orbit published precise orbit later published robert baker star system resolved pan mark iii stellar mount wilson observatory california united_states work published difference stars lines observed early 1990s observations pan james mccarthy published stars known orbit period days larger brighter star called primary type mass approximately solar masses surface temperature measured times sun smaller companion secondary mass approximately solar masses surface temperature measured times sun early type star type estimated chemical norman reported number unusual lines spectrum pointed unusual lines came similar lines present spectrum morgan identified additional stars lines appearing stars subsequently identified group mercury stars class peculiar stars excess elements mercury case brighter primary star mercury star elements mentioned excess suggested peculiar stars arose according theory stars unusually calm elements sink force gravity pushed surface radiation pressure theory successfully explained observed chemical including mercury stars primary reported slightly variable observations found constant magnitude workers discovered observations published mercury line spectrum varies primary distribution mercury atmosphere uniform applying imaging observations allowed find concentrated clouds near equator subsequent imaging studies published showed clouds drift slowly star surface etymology cultural significance names derive arabic mare word horse reflects star historical placement term star medieval writing arabic head woman chains woman arabic names include hindu lunar star stars great square makes chinese meaning wall refers consisting consequently known english second star wall known guides mark prime heavens beta gamma believed born influence honour observation location sky shown left seen naked eye theoretically visible latitudes north evening august october high sky seen northern optical companion system described optical visual companion discovered william july designated ads double star catalogue type star apparent visual magnitude approximately coincidence appears near stars sky close space


known hot discovered orbit star red giant planet noted transit event nasa spacecraft team data collected satellite publicly available including data french swiss equivalent night measurements collect data needed planet producing periodic planet twice mass slightly larger size making dense neptune planet nearly thirteen times times closer star mercury sun history observed spacecraft nasa satellite searches planets transit crossing host stars june days operation resulting light curve available public science team revealing transit events days team composed france switzerland observatory southern france examine uses radial velocity measurements examine stars background light removed alternative causes radial velocity variations example actually close star team analyze properties actual star observing star found nearing main sequence turn star hydrogen red giant establishment stellar parameters helped parameters prove existence discovered planet sixth planet discovered orbit stars radius times sun planets including discovery demonstrated smaller effective follow ups space missions like team spent amounted roughly night meter gathered data needed establish existence parameters published journal astronomy january sent journal september host star type star located star times mass sun times radius effective temperature larger massive sun means iron measured sun nearing main sequence turn words fuse hydrogen red giant hosts sixth system discovered orbit star mass solar masses lies light years away earth making distant previously verified planet discovered apparent magnitude invisible eye characteristics hot estimated times mass times mass earth times radius times radius earth planet density grams cubic centimeter similar neptune planet temperature estimated thirteen times temperature star days average distance meaning seen nearly edge respect earth comparison mercury sun days average distance orbit approximately thirteen times faster mercury times closer host star mercury sun


orbit red dwarf discovery announced february making eleventh planet discovered planet thought twice mass orbit percent larger earth lasting approximately days exact characteristics difficult characteristics host star known characteristics mass orbit gas giant estimated mass times estimated mean distance host star period approximately days mass mean distance estimated confidence intervals large indicating large uncertainty present largely exact parameters host star known host star planet known orbit star type dwarf star mass approximately times sun star located estimated light years earth star named observations group saw star event data hope discovering planet discovery event detected observations collaboration july searches documents chance brief stars stars objects cause lens effect bends light causes distorted images interpreted detection logged days south african astronomical observatory perth observatory hill observatory tasmania separation seven days events june long event subsided science teams studying star facility large chile determine actual apparent magnitude star background star hoping compare magnitude star measured event found result error body interpretation follow observations led planet confirmation ratio planet mass host star mass constrained large interval uncertainty exists host star mass known large confidence interval spans mass red dwarf stars discovery planet published february journal astronomy european southern observatory


known planet orbit star initially discovered spacecraft terrestrial planet searching satellite built operated nasa likely super earth estimated radius approximately larger earth exact mass determined days distance star extremely close distance closest planet star system named instead gas giants confirmed original studies system suggested planet follow investigation team later confirmed confirmation planet public team paper published journal january team observatory hawaii follow space initial discovery discovery comes planet discovered orbit named spacecraft nasa satellite aims discover terrestrial planets transit crossing host stars seen earth transit causes regular interval star briefly slightly planet crosses initially transit event satellite given designation recognized potential planet study system confirmed follow studies completed verify planet apparent transit event background star team small transit event planet results published journal january follow observations conducted high resolution observatory hawaii observatory arizona observatory california host star star lies away earth mass radius exactly size width sun massive wider effective temperature compared sun approximately metal rich terms iron sun younger sun estimated billion years old planets gas giants characteristics based size light curve assumed super earth exact mass known presumed earth masses planet radius approximately larger earth radius temperature previous planets discovered counting previously discovered ones located field view density known average distance miles star days closest planet star system compare planet mercury away sun days


star located field view mission nasa project aimed detecting planets transit passing host stars seen earth closely like planet named detected planet planets discovered spacecraft discovery announced january meeting american astronomical society verified variety larger massive sun similar major factor planet formation nomenclature history named fifth planet bearing star discovered course mission nasa operation seeks discover earth like planets transit cross host stars respect earth star planet second planets discovered spacecraft planets found tests discovered presented public january meeting american astronomical society washington planets initial discovery examined scientists observatory hawaii mcdonald observatory west texas california arizona los observatory islands characteristics star mass radius sun star making approximately metal rich sun increasing star likelihood planets orbit effective temperature sun effective temperature apparent magnitude seen naked eye system twice mass slightly halves radius star days lying approximately hot gas giant near host star compare mercury sun days planet assumed circular orbit


planet star located light years earth direction southern planet discovered radial velocity method apparatus june massive proposed planets system planet interest star relatively low supporting hypothesis different determine kind planets form discovery discovered method functions measuring variations radial velocity star produced effect radial measured high accuracy radial velocity planet system observatory chile desert massive planets discovered way discovery announced conference took place june france orbit mass mass times earth assuming planets system massive planet known system planet approximately astronomical units primary star compared earth orbit approximately astronomical unit away sun result year constitutes approximately earth days planet orbit found differ significantly zero meaning insufficient data distinguish orbit entirely circular star unusually low compared planet bearing stars supports hypothesis concerning possibility stars determine disk forms gas giants terrestrial planets characteristics planet found transit likely specific physical characteristics radius composition average surface temperature observed study planets showed tidal effects extent sub neptune planets migrated inward study implied sub neptune strong tidal forces result destruction larger natural satellites planets close star unlikely hosts satellites


yellow dwarf yellow star phoenix star visible naked eye lies approximately light years away sun relatively stable star times mass planet discovered orbit known 100th discovered nomenclature designation henry catalogue catalogue published based work annie jump cannon team common characteristic stars like characteristics stable type star meaning shines white light seen sun terms mass star exhibits identical properties exhibits radius approximately fifth times size sun star slightly sun temperature sun surface temperature lies nearly lower unusually metal rich attracted attention distance visibility star magnitude observed earth signifies body visible naked eye seen lies roughly light years sun far sun second star night sky system planet found anglo australian planet search team star eccentric orbit minimum mass times period years planet star distance approximately away planet earth comparison distance away sun discovery reported quietly press release provided observatory discovered star planet formal announcement planet existence entity 100th verified scientific community


designation triple star system approximately light years away earth consists sun like yellow dwarf stars red dwarf planet discovered eccentric orbit distance stars measured mission yielded components associated reasonable assume lie distance different result experimental error associated errors taken account ranges overlap component distance component corresponds distance stellar components triple system stars form close projected separation elements currently unknown distance component designated orbit relative pair determined updated june plausible range period million years axis ranging addition degrees pole degrees yellow dwarf stars like sun according data geneva copenhagen survey stars masses similar sun age estimates stars vary slightly likely older solar system million years old stars red dwarf system planet eccentric orbit announced star planet orbit takes days complete axis like majority planets earth radial velocity parent star time gave lower limit mass case times showed stable orbit demand masses orbit inclined system particles inside approximately remained stable million years formation leaving open possibility short period planets observation rules planet neptune mass message sent system transmitted largest radar meter foot radar message named cosmic sent reach november system field view space


yellow dwarf star similar sun located light years away earth designation refers entry henry catalogue star known possess long period planet distance visibility according measurements satellite corresponds distance light years star located earth listed catalogue nearby stars apparent magnitude star visible naked eye seen stellar characteristics similar sun terms mass radius star main sequence generating energy hydrogen core type implies cooler sun like majority planet host stars metal rich relative sun containing solar abundance iron star slower sun period days compared days sun based star activity estimated age million years hand evolutionary models age million years mass times sun higher longer rotation period favour older age star system planet similar size designated discovered orbit star period years unlike long period planets low planet experiences similar earth led possibilities addition numerical suggest low mass planets located gas giant points stable long periods planet existence independently confirmed planet search program star shows evidence long term radial velocity trend indicate presence additional outer companion


orange type main sequence star located approximately light years away taking primary henry catalogue designation calculated slightly massive sun observed cape photographic star known planets discovered potential super earth zone period days object capable supporting liquid water surface information acquired assessed history nomenclature designation henry catalogue based classifications annie jump cannon workers published characteristics type star orange light quarters sun radius mass temperature measured slightly relatively high type star approaching temperatures normally found type stars sun discovered planets suggested stars determine bodies orbit terrestrial like earth like saturn distance visibility despite relative proximity sun light years visible naked eye given apparent magnitude came light years sun years ago system spending years observing star european organisation astronomical research southern hemisphere announced discovered super orbit june planets detected radial velocity method system independent analysis carried team led university confirmed existence planets found additional planets systems planets orbit close star located twice close planet mercury sun planet distance similar distance venus sun situated system liquid water zone minimum masses planets system ranges times mass earth placing earth gas giants like neptune analysis planets suggests planet unstable age ice giant having migrated away implies similar planets recent discovery indicates analysis true masses higher minimum masses


object object star located thought previously white dwarf result late thermal pulse red giant located center believed currently thermal instability final shell flash phase time discovery believed object slow nova later analysis suggested star nova instead undergone late thermal pulse similar causing vastly expand discovered star known observed high phase late thermal pulse models predict object decades follow similar life cycle object similar stars expected end rich white evolution track born giant phase white dwarf cooling track suspected born objects example having erupted expected object final flash observed observation history international astronomical union circular sent february announced discovery possible slow nova magnitude amateur japanese reported discovery drawing attention fact object visible images harvard center records years despite appearing slowly previous years wrote suggests slow nova lack obvious lines year unusual following initial announcement published study investigating possible final flash seen noted location object corresponded faint object detected magnitude discussed observations years time magnitude increased investigating measured angular diameter mass distance determined researchers noted agreement appearance model predictions area solar lower predicted factor infrared observations published near far infrared data presented collected data showed object steep followed sharp decline expected later found star steep decline light dust located star present temperature infrared data recorded united_kingdom infrared published findings changing absorption lines discussed observations united_kingdom infrared revealed star like phase release dust huge loss mass observed ejected particles object carbon taking place properties object highly evolved post giant branch star following brief period white dwarf cooling track undergone shell flash known late thermal pulse star thought mass observations object increasing activity suggesting star exhibiting thermal instability final shell flash prior thought cooling white dwarf temperature rapidly increased fold temperature decreased star developed appearance class apparent temperature continued cool star gradually obscured optical formation carbon dust similar star temperature increased properties object similar discovered known star observed high phase late thermal pulse object modeled increase temperature decades match current state dust cloud second half thick dust shell obscured object causing rapid decrease visibility star disappeared optical observations altogether infrared observations showed dust cloud star primarily carbon form discovered dust shell strongly disc major axis oriented angle disc thought growing fast evolution source lower temperatures object surrounded created following star red giant phase years ago determined diameter expansion velocity roughly similarities stars research revealed object possessed characteristics variable star deficit object similar expected object grow match significance astronomical research significant new star formation star destruction data expected recorded continued observation object reference data future research similar stars reason stars object exist experience shorter lifespan compared stars largely unknown object observed experiencing born behavior years undergone behavior years object evolving giant branch stars time undergoing process second time


sun like star slightly larger sun located light years earth located field vision spacecraft satellite nasa mission uses detect planets stars announced february star system compact systems discovered discovered case star system planets discovered planets larger earth larger ones neptune size nomenclature history planets discovered nasa mission mission tasked discovering planets transit stars transit method uses involves detecting stars interpreted planets stars perspective earth discovered system planets named mission 11th star confirmed planets discovered field view planets named starting tagged home star characteristics type star approximately mass radius sun surface temperature estimated age billion years comparison sun billion years old surface temperature star apparent magnitude bright appears earth perspective seen naked eye system known planets transit star means planets appear cross star viewed earth perspective relative earth line sight far plane sight vary little degree allows direct measurements planets periods relative compared host star monitoring planet transit star suggest mean mutual meaning system probably solar system corresponding figure estimated masses planets fall range earth neptune estimated lower earth imply earth like composition significant hydrogen atmosphere predicted planets planet surrounded steam atmosphere hydrogen atmosphere low likely result high volume extended surround iron rock possibly inner constituents system time discoveries understood planets smaller neptune currently observations place firm mass planet formation evolution studies indicate mass planet greater planets formed observed locations started formation farther away star migrating inward interactions disk second scenario substantial fraction planets mass regardless formation scenario component planets accounts masses system compact known planets easily fit inside orbit mercury slightly outside despite close packing indicate system potential stable time scale years planets low ratio multiple planets stabilize resulting simple periods close ratio planets system transit star effects gravity motion visible planets neptune discovered


planet star located light years away direction southern planet discovered radial velocity method apparatus june proposed planets star system largest second closest orbit star planet interest star relatively low supporting hypothesis different determine kind planets form discovery like star discovered measuring variations radial velocity caused star orbit center mass system measurements high accuracy radial velocity planet apparatus observatory chile desert discovery planets system announced convention took place france mid june orbit mass massive planet system lower mass bound times mass earth planet astronomical units compared earth distance sun result year planet constitutes approximately earth days analysis radial velocity data detect planet yield significant circular orbit star planet low unusual compared planet bearing stars supports hypothesis concerning possibility stars determine disk forms gas giants terrestrial planets characteristics observed directly likely transit specific characteristics surface temperature composition radius determined small mass times earth assumed terrestrial later study stated terrestrial tidal heating manner greater process moon restrictions terrestrial planets restrict ice giant planets like neptune sub neptune tides predicted result destruction larger natural satellites planets located close parent star unlikely hosts satellites


confirmed nasa spacecraft confirmed days science operations star slightly significantly larger sun expected soon reach end main sequence hot half mass nearly times size time discovery second planet known surpassed host star days distance approximately announced meeting american astronomical society january planet crude map cloud coverage characteristics mass temperature orbit hot like close star temperature proximity star hot measured nearly planets discovered second surpassed times mass proximity star planet expanded radius mean density expanded substance manufacture lightweight commercial plastic products known lower density time discovery low predicted current standard theories planet formation host star days distance making planet discovered mercury contrast distance days addition observed means orbit edge seen earth cloud mapping data nasa space created cloud map planet cloud map created solar system visible light observations moon like phases led rough map planet showed bright spot western hemisphere data bright spot coming clouds heat space played crucial role answering question professor astronomy santa said clouds composed rock iron planet degrees degrees massachusetts institute technology noted oceans continents detected clear reflective signature detected interpreted cloud thomas scientist nasa research center said unlike earth cloud patterns planet change time remarkably stable climate host star largest host star planets detected situated star radius sun sun mass larger massive dense sun slightly sun effective temperature star near end life main sequence star means iron detected sun discovery nasa spacecraft completing tests instrument uses detect transit events planet crosses host star brief roughly regular period time test observed stars input catalog including preliminary light curves sent science team analysis chose obvious companions bunch follow original candidates resting period days began nonstop day period observed targets june collected data downloaded tested false candidate found false star generate light curve companions observed fed islands optical nights october taken respect star compensate possible error imaging star taken observatory arizona check close companions found high resolution instrument observatory hawaii smith mcdonald observatory texas camera observatory north observatory analyze candidate radial velocity observations confirmed body responsible observed light curve confirming planet discoveries including planets announced january meeting american astronomical society washington planet detected variations star cause reflected planet found relatively high geometric


discovered orbit sun like star named discovered nasa spacecraft named designed detect earth like planets measuring small host stars planets cross process known transit method note presence planets orbit star orbit mercury approximately days planet approximately times massive earth radius half times larger earth far earth low density comparable saturn suggests large hydrogen atmosphere announced sister planets february extensive follow studies discovery named host star announced time planets system names distances host star planet given designation named spacecraft nasa earth trailing satellite discovering earth like planets small area sky observing planets transit cross host stars respect earth transit causes star dim slightly regular rate phenomenon satellite notes till future study prove existence body given designation required follow observations conducted shane california observatory hawaii arizona hobby smith west texas additionally space sister planets announced public february discovery paper published journal nature day host star type star mass radius measured effective temperature near mass sun radius sun iron content sun observed play major role determining type planet star forms metal rich gas clouds tend cause aggregate prominent size gases exist system gas giants tend form conditions slightly cooler sun estimated billion years old far older sun host planets planets system collectively fit inside orbit planet mercury considerably distance relation inner counterparts distance apparent magnitude visible naked eye characteristics mass radius making times massive earth nearly half times radius density grams density water comparable gas giant saturn suggests unlike sister planets closer host star maintained large atmosphere likely composed hydrogen temperature nearly times temperature earth mean distance host star completes orbit days making planet comparison planet mercury sun days distance exactly edge respect earth presence large quantities hydrogen suggest planets formed million years system existence gas captured forming disc


star system consisting pair type dwarf stars orbit period years apparent magnitude respectively seen city skies naked eye rural areas light pollution attracted attention large proper motion demonstrated friedrich measured distance earth light years close actual value light years distance estimate star sun star stellar measured stars stellar systems listed modern catalogue currently seventh highest proper motion highest visible stars systems course twentieth century different reported evidence massive planet stars recent high precision radial velocity observations shown claims planets confirmed stellar system date relatively dim appear ancient star maps given western chinese systems designation assigned stars according designation scheme devised john catalog observations stars particular numbered order right ascension greek letters designation star appear stated actually corresponds referred edition called star flying star observation history early observations recorded observation star system optical instruments james bradley september noticed double star william began systematic observations wider study stars observations led conclusion stars separated different movements year hoped use way measure distance stars noticed high proper motion compared observations bradley years earlier led considerable interest contemporary continual observation date repeated measurements led definitive value motion published record christened system flying star noted motion meant probably closest stars suggested prime candidate attempt determine distance measurements possibilities delta measurement number soon took task including attempts louis recorded distance christian friedrich data value calculated better value based observations von calculated von noted seen friedrich von pointed test series numbers accurate accuracy instrument friedrich notable contribution different method measure distance assuming period stars years estimated distance require measured angular distance stars led value followed direct measurements series observations comparing stars sets measurements produced values estimates like earlier attempts retained greater measurements joseph von invented new type carried set measurements device published findings value estimated center point corresponds distance astronomical units light years direct reliable measurement distance star sun measurement published shortly similar measurements friedrich von alpha thomas henderson year continued additional measurements publishing total complete runs best placed center point observations close currently accepted value yielding light years years measurement friedrich noted larger proper motion second highest known later moved list star star currently seventh highest proper motion stellar systems listed modern catalogue retains title highest proper motion visible stars observations improved measurement corresponds motion transverse line sight observations observatory measured radial velocity measurements yielded space velocity moving point degrees west belt observations wide angular separation slow motion initially unclear stars system bound system simply stars von argued status matter remained open refined measured differences demonstrated separation significantly nature system clear elements published benjamin boss published data indicating system member group stars group containing later expanded include potential members possible members include beta space group stars range relative sun amateur observation observer find fields southeast bright star angular separation stars slightly greater angular size saturn ideal viewing conditions system resolved capability typical resolve need steady mount separation arc seconds component stars apparent separation arc seconds generally regarded eye resolution limit arc minutes arc seconds properties appears single star naked eye fact widely separated star system composed class orange main sequence stars brighter apparent respectively appear old disk stars estimated age older sun system net space velocity relative sun results high proper motion sky distance light years 15th nearest known star system earth including sun fourth nearest star visible naked eye mid latitude northern observers system closest approach separation sun light years long term stability led selected anchor star morgan classification system serving anchor point time starting considered standard star johnson morgan typical variable star designated type variable star named varying respectively stars orbit common period years mean separation times separation earth sun relatively large means stars separated orbit pair difficult pin respective masses accuracy values remain somewhat controversial future issue resolved use mass activity cycle pronounced solar cycle complex activity cycle varies period years earlier estimate gave period years combination activity combined rotation activity characteristic variable differential rotation star surface rotation period varies latitude days average period days outflow stellar wind component produces bubble local cloud direction star motion way extends distance roughly distance neptune sun lower separation components likely share common atmosphere likely low mass outflow relatively high velocity local medium displays chaotic pattern significant short term year overall activity cycle stars exhibit stellar activity active result differential rotation period rotation varies latitude days average period days disagreement evolutionary age system data gives age estimate age determination star based rotation color results average age ages based activity respectively finally age estimates method involve fitting stars evolutionary models yield upper limits evolutionary model code observatory gives age estimate pair claims system occasions claimed unseen low mass companions planets brown dwarf strand observatory direction peter van claim observations detect tiny systematic variations motions suggested body masses reports body served inspiration science fiction novel mission gravity van narrowed claiming object mass times calculated period years semi major axis soviet observatory near saint_petersburg suggested system included planets giant planets masses giant planet seven masses observatory proved claims claims unseen companions stars having failed detect evidence motion percent sun mass equivalent times mass zone defined locations liquid water present earth like planet average distance earth sun zone boundaries certain object detected star far mcdonald observatory team set limits presence planets masses masses average spanning proximity system sun frequent target interest stars selected nasa tier targets proposed optical space mission mission potentially capable detecting planets little times mass earth distance star measurements system appeared detected excess far infrared radiation emitted stars excess associated disk dust case lies sufficiently close stars resolved study failed detect dust


red dwarf approximately light years away earth second closest known star sun confirmed possess system closest system known consist multiple planets planets found orbit star system notable properties planets known system companions exhibit triple conjunction rare phenomenon resonance type resonance noted inner system normal star measured middle planets located system zone giant planets believed analogous distance visibility located fairly close solar system according measurements satellite star shows corresponds distance currently making closest known star planets despite located close earth star faint invisible naked eye seen stellar characteristics red dwarf massive sun estimates suggest mass sun surface temperature cooler sun star smaller radius factors combine star sun infrared estimating age cool stars difficult formation molecules makes spectrum extremely complex fitting observed spectrum model estimated slightly lower abundance heavy elements compared sun solar abundance iron based activity star likely billion years old depending theoretical model low period star membership young disk population suggest star billion years old like low mass stars variable star variable star designation classified variable type thought caused large moving view star rays system observation history june planet announced orbit independent teams led planet designated detected based measurement zone believed located april second planet designated detected inside orbit previously discovered planet relationship periods initially disguised planet radial velocity signature increased outer planet rivera found planets undergo strong interactions orbit star causing elements change rapidly june observations team led rivera revealed planet designated inside size planets january mutual planets determined combination radial velocity measurements planets found angle planes june announced fourth planet designated discovery better constrained mass properties planets including high planet filled system inside orbit additional planets unstable system age evidence presence newly discovered planets having mass system disc brighter dust recent study planets transit star perspective earth making difficult study properties arrangement notable arrangement system normal star mutual planets measured previously mutual planets determined measuring interactions later measurements reduced value mutual latest planet models incorporation mutual result significant improvements relative solutions system second known example resonance resonance planets known example closest numerical integration indicates planet system stable billion years system comes close triple conjunction outer planets orbit planet planets known planets likely formed away star migrated inward discovered known planet estimated minimum mass times earth possible dense terrestrial planet discovered giant planet mass planet resonance known planet taking days orbit star planet zone mass makes likely class planet planet classification presence surface liquid water possible sufficiently massive satellites exist discovered twice mass revolves star orbit taking approximately days complete distance distance sun mercury mass makes likely class class iii planet model presence surface liquid water possible sufficiently massive satellites exist discovered mass similar planet orbit takes days complete


magnitude star located light years away star massive larger sun metal rich sun known planet orbit planet hot high radius phenomenon explained presence internal heat source star observed program future measurements follow observations analysis eventually led discovery transit method history observed south african astronomical observatory coordinates planet searching program southern hemisphere wasp south coordinates sky information captured camera field july later overlapping camera fields january july january data processing led acquisition data points suggested body crossed briefly days approximately partial observed use observatory march provided evidence better defining transit curve later march july collect radial velocity measurements analysis confirmed presence planet later designated characteristics type star mass times larger sun radius bigger larger massive sun star effective temperature making sun times iron sun consistently lower levels metals including calcium addition likely younger sun estimated age billion years approximately times sun located distance light years estimated apparent magnitude visible earth eye system host planet planet hot host star distance days noted high radius times compared mass times size large radius explained solely proximity star suggesting form tidal heating internal heating mechanism involved


planet located approximately light years away star planet minimum mass distance earth sun planet elliptical orbit led planet surface temperature varies entire orbit planet reported september discovery las observatory planet observed years consortium follow observations collected radial velocity measurements necessary confirm candidate planet discovery designation henry catalogue star observed released catalogue observations led discovery planet started consortium started extended search planets stars usually targeted surveys case star observed las observatory chile selected primarily metal rich star collaboration biased search metal rich stars closely size planets hoping find connection star planets masses originally candidate hosting hot large gas giant closely star later observations suggested candidate years observation star studied mike ability use measure radial velocity measurements recorded measurements analyzed accuracy derive planet characteristics led planet confirmation team united_states chile vatican city sent paper astronomical journal april paper accepted later published october host star type star mass times mass sun size times radius sun words slightly massive slightly larger sun effective temperature sun younger estimated age billion years star rich iron measured times iron detected sun analysis spectrum concluded layer active seen earth naked eye star apparent magnitude characteristics size planet estimated minimum mass times mass planet found orbit host star days distance approximately mean distance sun earth mildly elliptical orbit given planet elliptical orbit typical respect discovered planets longer days grown circular tidal forces according elongated orbit causes surface temperature


planet approximately light years away earth fish planet second planet discovered star existence inner planet orbit confirmed radial velocity studies star indicated distant massive companion star planet eccentric orbit lasting order decade detection discovery study radial velocity carried revealed motion line sight varied day cycle indicating presence planet orbit star planet designated found somewhat heavier extremely close parent star orbit large planets periods days circular proposed high orbit influence second planet system distance astronomical units confirmation existence second planet followed designated parameters planet initially weakly constrained period excess years high minimum mass approximately times mass continued observations restrained plausible solutions substantially resulting current parameters published


planet approximately light years away planet discovered sun like star solar mass components triple star system makes revolution days eccentric planet triple star system discovered discovery october discovery mass companion star announced mass times time highest known planet discovery measuring star radial velocity orbit directly measured dynamic model system published lower limit mass determined orbit mass unlike planets solar system planet orbit highly elliptical distance varies high caused tidal interactions star system planet orbit vary low high states period tens millions years preliminary measurements suggested orbit highly inclined respect line sight mean object mass dividing line planets brown measurements later proved useful upper limits mathematical study showed mass stable system body true planet tidal effects age gas giant stable physical characteristics planet detected indirectly measurements parent star properties radius composition temperature unknown zone planet highly eccentric orbit means planet experience extreme seasonal effects despite suggest earth like moon able support liquid water surface course year eccentric orbit massive gas giant unlikely planet survive system


closely sized planet found orbit star program searches planets cross host stars seen earth follow observations radial velocity planet confirmed use observatory detected star planet completes orbit star half days roughly host star discovery reported royal astronomical society discovery wasp south station south african astronomical observatory project searched night sky potential planets crossed host stars roughly periodic rate candidates identified possible host transit event potential host came wasp south july november combination later observations wasp south north islands measurements collected later set observations august november produced point data set light curve prepared late considered discovery paper star observed time stars european team chile observatory radial velocity measurements detected detected planet confirmed analysis results ruled stars leaving planet likely cause radial velocity variations observe host star hours september observed search slight precise light curve found accounting data collected analysis yielded planet characteristics discovery reported royal astronomical society scientists worked paper discussed role elliptical orbit poorly constrained tends hot circular orbit assumed newly discovered planets studies creation non eccentric circular model planet orbit likely solution eccentric elliptical solution planet orbit solution according discovery team required assumption host star type star mass solar masses radius solar means mass size sun effective temperature cooler sun richer iron measured times iron found sun star estimated million years old age uncertain error bars large based spectrum active outer layer star found demonstrate high rate rotation apparent magnitude seen eye earth characteristics hot mass times mass radius times massive planet greater size proximity host star heats common effect closely gas giants mean distance distance earth sun orbit completed days hours edge seen earth


yellow star approximately light years away earth fish mass similar sun considerably older planets discovered star extremely close completes orbit seven days distant taking years complete orbit distance age mass fairly close sun satellite measured corresponds distance light years apparent magnitude making barely visible naked eye favourable conditions observations type means temperature mass thought roughly sun estimated age billion years older sun billion years thought beginning evolve away main sequence having consumed hydrogen core nuclear fusion reactions system study radial velocity carried revealed motion line sight varied day cycle period variation indicated caused companion orbit star minimum mass slightly greater companion planet designated planets periods days circular somewhat eccentric orbit influence second planet system distance astronomical units confirmation existence second planet followed long term observations star radial velocity variations revealed variation period years caused planet mass twice eccentric orbit axis second planet designated


abbreviated star approximately light years away earth cancer system consists type star designated named smaller red dwarf planets designated named respectively believed orbit nomenclature system designation bears designation bright star catalogue designation components designated referred planet discovered designated commonly referred rules naming objects star systems named formal form occasionally avoid confusion secondary star planets discovered designated order discovery july international astronomical union launched process giving proper names certain host stars process involved public nomination voting new names december announced winning names planets respectively winning names submitted royal netherlands association astronomy netherlands honor thomas spectacle makers pioneers originally announced winning january recognition actual error introduced 19th century corrected submitted official sites track astronomical information stellar system system located fairly close solar system satellite measured corresponding distance light years apparent magnitude making visible naked eye dark skies red dwarf 13th magnitude visible components separated estimated distance thousand times distance earth sun despite wide separation stars appear bound share common proper motion primary star yellow dwarf star main sequence type smaller radius slightly massive sun cooler star low variable visible spectrum variable rays enriched sun elements heavier solar abundance iron classified rare super metal rich star abundance metal makes estimating star age mass difficult evolutionary models defined stars age estimates include billion years billion years hypothesis high metal content dwarf stars material enriched heavy elements fell atmosphere disk star external layers resulting higher normal lack deep convection zone mean outer layers retain higher abundance heavy elements observations region spectrum far failed detect associated dust upper limit emissions star limits total mass fine dust star earth mass exclude presence belt belt equivalent secondary red dwarf star massive sun indications component double star uncertain system system known later planets possibly planet viewed earth planet non tentative evidence surrounded extended atmosphere transit star discovery like planet announced planet inner planet planet discovered measuring star radial velocity showed days corresponding planet mass radial velocity measurements showed drift planet explained influence distant object discovery possible dust disk announced calculations gave disk radius similar belt solar system respect plane sky discovery verified later deemed caused instead background radiation making radial velocity measurements planet distance announced planet received designation time discovery planet thought orbit mild close value increased later measurements accounting planets days remained possibly planet measurements star suggested close star rotation period raised possibility day signal caused stellar activity possible planet received designation announced earth masses large super earth originally thought period days later found alias true period days observations planet instance fourth planet system shortest period planet discovery measurements led discovery planet confirmed existence jack wisdom suggested actually period days mass similar neptune day orbit corresponding distance planets found conflict occurrence fifth planet system announced similar mass day orbit inner edge zone planet thought life hypothetical principle maintain life planet poorly defined varying values significantly improve fit assumed taking interactions planets account results near zero observations space measured outer planet result relies precise parameters substantially revised published observed suggest orbit normal inclined line light possible detection transit extended atmosphere confirmed imply orbit close edge measurement thought planets system far order maintain stability attempt measure spin orbit planet reported nearly polar orbit interpretation data challenged subsequent study noted inconsistencies implied measured stellar rotation approximate periods adjacent proceeding outward nearly ratio apparently near resonance genuine mean motion resonance planets possible stable zone given hypothetical planet earth masses stable mean motion resonance regions lie space outside orbit stability zone begins stability zone resonance communication message sent transmitted largest radar meter foot radar message named cosmic sent july arrive


discovered star spacecraft nasa led mission discover earth like planets times massive twice large earth lower density likely earth like composition hottest planets system closely planets system counterparts form discovered system planets densely packed known system system known system discovery planet sister planets announced february follow investigations naming discovery named parts derived fact star discovery announced simultaneously planets given designation announced planets host star named mission host potential transit events satellite nasa run space tasked discovery terrestrial planets transit cross host stars seen earth cause fluctuations host star changes suggest presence planet verified follow observations ground based california hawaii islands arizona texas space conduct follow observations verify existence particular detection resonance effect confirmed find discovery announced public february system discovered planets compact flat system discovered system second known system multiple planets surpassing confirmed planets star host star star mass radius words approximately massive wider sun star meaning level iron presumably elements star sun plays important role systems stars higher likely planets detected higher provides material quickly build planets gas giants higher increases planet migration host star making planet easier detect star known planets orbit planets system able fit orbit planet mercury apparent magnitude dim earth naked eye characteristics estimated earth masses earth making times massive nearly twice large earth radius fairly known range likely earth mass constrained range earth masses mass determined transit timing variations limited quality data closest planet host star system estimated density comparable neptune solar system gas giants significantly dense terrestrial planets estimated density range suggests earth like composition nonetheless composed elements heavier planet effective temperature hottest planets discovered system host star days distance planet mercury comparison sun days distance means slightly plane planets discovered close proximity star implies strong caused planet lose light element envelope acquired formation observed low density require presence envelope likely produced hydrogen condensed core orbit strong resonance planets stable set ratio ratio resonance


galaxy galaxy known spiral galaxy approximately million light years earth nearest major galaxy way referred great older texts received area sky appears named mythological princess approximately light years largest galaxy local group contains way galaxy smaller despite earlier findings suggested way contains dark matter largest grouping observations space revealed contains stars twice number stars way estimated billion mass galaxy estimated solar masses way estimated solar masses comparison study estimated way equal mass study mass way mass galaxy way expected billion years eventually merging form giant elliptical galaxy large disc galaxy apparent magnitude galaxy objects making visible naked eye nights viewed areas moderate light pollution appears times wide moon photographed larger brighter central region visible naked eye viewed small making appear similar star observation history year persian described galaxy book fixed stars star charts period labeled little cloud german simon gave early description galaxy based observations charles object incorrectly credited despite visible naked eye william noted faint reddish core region believed nearest great based color magnitude incorrectly times distance william parsons 3rd earl saw drawing spiral structure william observed spectrum noted differs displays frequencies superimposed dark absorption lines help identify chemical composition object spectrum similar individual stars stellar nature known seen far observed galaxy time considered nearby object cause thought unrelated event called nova named accordingly nova roberts took photographs commonly thought galaxy roberts actually similar spiral solar systems formed measure radial velocity respect solar system largest velocity measured kilometres second island universe american curtis observed nova searching photographic record discovered curtis noticed average occurred sky result able come distance estimate light years proponent called island hypothesis held spiral actually independent great debate curtis took place concerning nature way spiral dimensions universe support claim great fact external galaxy curtis noted appearance dark lanes resembled dust clouds galaxy historical observations significant shift presented method estimate distance measured stars result placed far outside galaxy distance settled debate identified extra variable stars time astronomical photos metre enabled distance great determined measurement demonstrated feature cluster stars gas galaxy entirely separate galaxy located significant distance way plays important role studies nearest major galaxy nearest galaxy walter person resolve stars central region galaxy identified distinct populations stars based naming young high velocity stars disk type older red stars type nomenclature subsequently adopted stars way existence distinct populations noted earlier jan discovered types resulted doubling distance estimate remainder universe radio galaxy detected brown hazard bank observatory transit announced earlier observations radio astronomy pioneer inconclusive later shown order magnitude high radio maps galaxy 1950s john baldwin collaborators cambridge radio astronomy group core galaxy called radio astronomy catalogue planet discovered galaxy detected technique called caused light massive object general estimated distance galaxy doubled discovered type 1990s measurements standard red giants red stars satellite measurements distances formation history according team reporting formed collision smaller billion years ago paper published outlined basic history birth according born roughly billion years ago merger smaller leading galaxy smaller today important event history merger mentioned took place billion years ago violent collision formed metal rich halo extended disk star formation high point infrared galaxy roughly million years galaxy close passage billion years ago event produced high levels star formation galaxy disk clusters disturbed outer disk activity billion years lower past star formation disk thought decreased point near inactivity activity increased relatively recently interactions satellite like absorbed interactions formed structures like giant stellar stream merger roughly million years ago believed responsible counter rotating disk gas found center presence relatively young million years old stellar population recent distance estimate distinct techniques estimate distances galaxy infrared surface fluctuations adjusting new period value correction estimate million light years derived variable method estimate million light years reported institute space studies colleagues announced discovery star galaxy star designated hot blue stars types studying stars occur days able measure sizes knowing sizes temperatures stars able measure absolute magnitude visual absolute known distance star measured stars lie distance galaxy new value excellent agreement previous independent based distance value close tip red giant branch method estimate distance estimated distance technique yielded averaged distance estimates combined value diameter widest point estimated applying angular diameter equivalent apparent angle sky mass estimates mass mass estimates galaxy halo including dark matter value approximately solar masses compared way earlier measurements indicate way equal mass actually higher stellar density way stellar disk twice size way total stellar mass estimated twice massive way according estimates mass central disk remaining halo addition medium contains form neutral hydrogen molecular hydrogen dust studies help space published uncovered large massive halo hot gas halo estimated contain half mass stars galaxy halo times larger times massive previously measured nearly invisible halo stretches million light years host galaxy halfway way galaxy indicate halo formed time galaxy halo enriched elements heavier hydrogen formed properties expected galaxy lies green valley color magnitude star filled disk heavier elements space lifetime nearly half heavy elements stars ejected far galaxy light year diameter stellar disk appears significantly common stars way old stars ages years estimated higher galaxy galaxy high seen earth dust unknown light difficult estimate actual authors given values galaxy including propose second galaxy radius mega way galaxy absolute magnitude close help space published suggests absolute magnitude blue color index translates absolute visual magnitude compared way total rate star formation way higher producing solar mass year compared solar masses way rate way double suggests experienced great star formation phase relative state way experiencing active star formation continue way eventually overtake according recent studies like way galaxy lies galaxy color magnitude known green valley region populated transition blue cloud actively forming new stars red sequence lack star formation star formation activity green valley slowing run star forming gas medium simulated similar properties star formation typically extinguished billion years accounting expected short term increase rate star formation collision way structure based appearance visible light galaxy classified galaxy extended classification system spiral data survey showed box like appearance implies galaxy actually barred spiral galaxy like way galaxy bar viewed directly long axis stars extending outward galaxy actually main disk means spiral disk stars times larger diameter previously estimated constitutes evidence vast extended stellar disk makes galaxy light years diameter previously estimates galaxy size ranged light years galaxy inclined estimated relative earth angle viewed directly analysis cross shape galaxy appears demonstrate pronounced shaped warp flat disk possible cause warp interaction satellite near galaxy responsible warp arms precise distances radial required studies provided detailed measurements velocity function radial distance core velocity maximum value kilometres second light years core minimum possibly low kilometres second light years core velocity rises radius light years reaches peak kilometres second slowly decline distance dropping kilometres second light years velocity measurements imply concentrated mass nucleus total mass galaxy increases light years slowly radius spiral arms outlined series regions studied great detail walter described resembling string studies spiral arms appear tightly wound widely spaced galaxy descriptions spiral structure arm crosses major axis follows galaxy seen close edge studies spiral structure difficult stated images galaxy fairly normal spiral galaxy arms wound clockwise direction exhibiting continuous trailing arms separated minimum light years followed outward distance roughly light years core alternative spiral structures proposed single spiral arm pattern long thick spiral arms likely cause spiral pattern thought interaction galaxy satellites seen displacement neutral hydrogen clouds stars images european space agency infrared space observatory demonstrated overall form galaxy transitioning ring galaxy gas dust generally formed overlapping rings particularly prominent ring formed radius light years core nicknamed ring fire ring hidden visible light images galaxy composed primarily cold dust star formation taking place concentrated later studies help space showed spiral structure infrared appears composed spiral arms emerge central bar continue large ring mentioned arms continuous structure close examination inner region showed smaller dust ring believed caused interaction million years ago smaller galaxy passed disk galaxy polar axis collision stripped half mass smaller created ring structures existence long known large ring like feature gas newly discovered inner ring like structure offset suggested nearly head collision satellite version encounter studies extended halo roughly comparable way stars halo generally metal poor increasingly greater distance evidence indicates followed similar evolutionary paths likely low mass past billion years stars extended way extend nearly distance separating nucleus known harbor dense compact star cluster center large creates visual impression star embedded surrounding nucleus excess clusters board space image inner nucleus nucleus consists concentrations separated brighter concentration designated offset center galaxy concentration falls true center galaxy contains black hole measured velocity material measured scott proposed observed double nucleus explained projection disk stars eccentric orbit central black hole stars creating concentration stars contains compact disk hot class stars stars evident filters blue light dominate nucleus causing appear prominent initial time discovery brighter portion double nucleus remnant small galaxy longer considered viable explanation largely nucleus short lifetime tidal disruption central black hole partially resolved black hole stabilize distribution stars suggest black hole center sources apparently late rays detected galaxy balloon flight october set upper limit hard rays multiple ray sources detected galaxy observations newton observatory robin candidate black holes stars heating incoming gas millions rays spectrum stars black holes distinguished masses approximately clusters associated galaxy massive clusters identified nicknamed greater known cluster local group contains million stars twice known cluster way stellar populations structure massive ordinary result consider remnant core dwarf galaxy consumed distant past greatest apparent located south west arm eastern half massive cluster discovered heavily galaxy dust thought massive largest cluster local group studies shown actually similar properties unlike clusters way relatively low age clusters larger range ages systems old galaxy younger systems ages million years billion years discovered completely new type star cluster new found clusters contain hundreds thousands stars similar number stars found clusters distinguishes clusters larger light years hundreds times dense distances stars greater newly discovered extended clusters year radio burst smaller black hole detected galaxy black hole located near center formula discovered data collected newton probe subsequently observed nasa swift large array long array observed galaxy outside way galaxy satellites like way galaxy satellite consisting known dwarf best known readily observed satellite based current evidence appears underwent close encounter past larger galaxy stellar disk removed underwent sharp increase star formation core region lasted relatively recent past appears interacting found halo stream metal rich stars appear stripped satellite contain dusty lane indicate recent ongoing star formation discovered lie plane intersects core galaxy randomly arranged expected independent interactions indicate common tidal origin satellites collision way galaxy approaching way kilometres second measured approaching relative sun kilometres second sun center galaxy speed approximately kilometres second makes observe ways velocity respect way relatively smaller approaching velocity expected directly way billion years likely outcome collision merge form giant elliptical galaxy large disc galaxy events frequent galaxy groups fate earth solar system event collision currently unknown merge small chance solar system ejected way join


planet discovered collaboration seeks discover transit host stars planet host star distance days mass planet half radius nearly larger making density planet quarter water thought form heating explain extremely low density discovery published april discovery observed wasp south branch project operates south african astronomical observatory july later observed wasp south north based islands january july january analysis taken collected data points revealed partial follow observations conducted european american science team observatory chile raised possibility existence planet orbit use march july revealed variations radial velocity measurements star system high resolution hires revealed spectrum derive star characteristics science team studying found running best fit models radial velocity transit shifts likely existence planet planet lowest known planets discovered discovery paper published american astronomical society april astronomical journal host star type star located located approximately light years earth apparent magnitude making invisible eye star times massive sun radius times larger sun making effective temperature sun billion years younger means iron found sun characteristics mass times mass radius times radius proximity host star distance greatly inflated density factor internal heat source suspected add extremely high radius extremely low density host star days making edge seen earth perspective