사용자:Ta183ta/연습장: 두 판 사이의 차이

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'''NGC 4993''' 또는 '''NGC 4994'''는 지구로부터 바다뱀자리 방향<ref name=":4">{{cite web|url=http://www.docdb.net/show_object.php?id=ngc_4993|title=NGC 4993|website=Deep Sky Observer's Companion|accessdate=28 August 2017}}</ref>으로 약 1억 4천만 광년 떨어져 있는<ref>{{Cite web|url=http://ned.ipac.caltech.edu/cgi-bin/objsearch?objname=NGC+4993&extend=no&hconst=73&omegam=0.27&omegav=0.73&corr_z=1&out_csys=Equatorial&out_equinox=J2000.0&obj_sort=RA+or+Longitude&of=pre_text&zv_breaker=30000.0&list_limit=5&img_stamp=YES|title=Your NED Search Results|website=ned.ipac.caltech.edu|access-date=2018-06-05}}</ref> 렌즈형은하<ref name=":2" />이다. 윌리엄 허셜이<ref name=":4" /><ref name=":5">{{Cite web|url=https://cseligman.com/text/atlas/ngc49a.htm#4993|title=New General Catalog Objects: NGC 4950 - 4999|website=cseligman.com|language=en-US|access-date=2018-06-05}}</ref> 1789년 3월 26일<ref name=":5" /> 발견했으며 NGC 4993 그룹의 구성원이다.<ref name=":3">{{Cite journal|title=The Distance to NGC 4993: The Host Galaxy of the Gravitational-wave Event GW170817|journal=The Astrophysical Journal|last=Hjorth|first=Jens|last2=Levan|first2=Andrew J.|date=2017-10-16|volume=848|issue=2|pages=L31|language=en|arxiv=1710.05856|bibcode=2017ApJ...848L..31H|doi=10.3847/2041-8213/aa9110|last3=Tanvir|first3=Nial R.|last4=Lyman|first4=Joe D.|last5=Wojtak|first5=Radosław|last6=Schrøder|first6=Sophie L.|last7=Mandel|first7=Ilya|last8=Gall|first8=Christa|last9=Bruun|first9=Sofie H.|hdl=2381/41880}}</ref>

 

 

==물리적 특징==

[[GRB 170817A]] was a [[gamma-ray burst]] (GRB) detected by [[NASA]]'s [[Fermi Gamma-ray Space Telescope|Fermi]] and [[ESA]]'s [[INTEGRAL]] on 17&nbsp;August 2017.<ref name="NG-20170825"/><ref name="FERMI-20170817">{{cite web |last=von&nbsp;Kienlin |first=Andreas |title=GCN Circular Number&nbsp;21520; GRB&nbsp;170817A: Fermi GBM detection; 2017-08-17 20:00:07&nbsp;GMT |url=https://gcn.gsfc.nasa.gov/gcn3/21520.gcn3 |date=17 August 2017 |work=[[Max Planck Institute for Extraterrestrial Physics]] |accessdate=28 August 2017 }}</ref><ref name="NAT-20170825">{{cite news |last=Castelvecchi |first=Davide |title=Rumours swell over new kind of gravitational-wave sighting |url=https://www.nature.com/news/rumours-swell-over-new-kind-of-gravitational-wave-sighting-1.22482 |date=25 August 2017 |publisher=[[Nature (journal)|Nature News]] |doi=10.1038/nature.2017.22482 |accessdate=27 August 2017 }}</ref><ref name="WIRED-20170825">{{cite journal |last=Sokol |first=Joshua |title=What Happens When Two Neutron Stars Collide? |url=https://www.wired.com/story/what-happens-when-two-neutron-stars-collide-scientific-revolution/ |date=25 August 2017 |journal=[[Wired (magazine)|Wired]] |accessdate=28 August 2017 }}</ref> Although only localized to a large area of the sky, it is believed to correspond to the other two observations,{{r|NYT-Dennis}} in part due to its arrival time 1.7&nbsp;seconds after the GW event.

 

 

{{Reflist|colwidth=30em}}

 

{{위키공용분류}}

* {{cite simbad|title=NGC 4993|access-date=28 August 2017}}

* {{cite web|title=New General Catalog Objects: NGC 4950 – 4999|url=http://cseligman.com/text/atlas/ngc49a.htm#4993|accessdate=28 August 2017|last=Courtney Seligman}}

* {{cite web|title=Revised NGC Data for NGC 4993|publisher=SEDS|url=http://spider.seds.org/ngc/revngcic.cgi?NGC4993|accessdate=28 August 2017|last=Hartmut Frommert}}

* [https://www.eso.org/public/images/eso1733l Starmap]