View source for GRS 1915+105

{{Short description|Binary system in the constellation Aquila}}
{{Starbox begin}}
{{Starbox image
| image = [[Image:V1487AqlLightCurve.png|250px]]
| caption = A near-infrared ([[Photometric_system#Photometric_letters|K band]]) [[light curve]] for V1487 Aquilae, adapted from Neil ''et al.'' (2007)<ref name="Neil"/>
}}
{{Starbox observe
| epoch=[[J2000.0]]
| constell=[[Aquila (constellation)|Aquila]]
| ra={{RA|19|15|11.6}}<ref name=liu/>
| dec= {{DEC|+10|56|44}}<ref name=liu/>
}}
{{Starbox character
| type = [[Microquasar]]<ref name=reid/>
| class=KIII<ref name=abubekerov/>
| appmag_v=
}}
{{Starbox astrometry
| parallax=0.120
| p_error=0.009
| parallax_footnote=<ref name=reid/>
| dist_ly=28,000
| dist_pc={{val|8,600|2,000|1,600|fmt=commas}}<ref name=reid/>
}}
{{Starbox detail
| component1 = Black hole
| mass = {{val|12.4|2.0|1.8}}<ref name=reid/>{{contradiction-inline|date=April 2024}}
}}
{{Starbox catalog
| names=[[Variable star designation|V1487]] Aquilae, [[Granat]] 1915+105, Nova Aquilae 1992, [[Granat]] 1915+10, [[INTEGRAL|INTEGRAL1]] 112
}}
{{Starbox reference
| Simbad = grs1915%2B105
}}
{{Starbox end}}
'''GRS 1915+105''' or '''V1487 Aquilae''' is an [[X-ray binary]] star system containing a [[main sequence star]] and a [[black hole]]. Transfer of material from the star to the black hole generates a [[relativistic jet]], making this a [[microquasar]] system. The jet exhibits apparent [[superluminal motion]].
It was discovered on August 15, 1992 by the WATCH all-sky monitor aboard [[Granat]].<ref name=cs1992/> "GRS" stands for "GRANAT source", "1915" is the [[right ascension]] (19 hours and 15 minutes) and "105" reflects the approximate [[declination]] (10 degrees and 56 arcminutes). The near-infrared counterpart was determined by spectroscopic observations.<ref name=cs1996/>
The binary system lies 11,000 [[parsec]]s away<ref name=Fenderetal/> in [[Aquila (constellation)|Aquila]]. The black hole in GRS 1915+105 is 10 to 18 [[solar masses]]<ref name=greiner/>{{contradiction-inline|date=April 2024}}. The black hole rotates at least 950 times per second, giving it a [[black hole spin parameter|spin parameter]] >0.82 (1.0 is the theoretical maximum).<ref name="space-paper"/><ref name=space/>
== Galactic superluminal source ==
[[Image:Merlin-GRS1915.gif|thumb|left|A sequence of [[MERLIN]] observation of the [[X-ray binary]]  '''GRS 1915+105''' taken over a few days.]]
In 1994, GRS 1915+105 became the first known galactic source that ejects material with apparent [[superluminal motion]] velocities.<ref name=mirabel/>
Observations with high resolution radio telescopes such as [[Very Large Array|VLA]], [[MERLIN]], and [[VLBI]] show a bi-polar outflow of charged particles, which emit [[synchrotron radiation]] at radio frequencies. These studies have shown that the apparent superluminal motion is due to a relativistic effect known as [[relativistic aberration]], where the intrinsic velocity of ejecta is actually about 90% the speed of light.<ref name=Fenderetal/>
== Growth regulation ==
Repeat observations by the [[Chandra X-Ray Observatory]] over the period of a decade have revealed what may be a mechanism for self-regulation of the rate of growth of GRS 1915+105.  The jet of materials being ejected is occasionally choked off by a hot wind blowing off the accretion disk.  The wind deprives the jet of materials needed to sustain it.  When the wind dies down, the jet returns.<ref name=nasa/>
{{Clear|left}}
== See also ==
* [[GRO J1655-40]]
==References==
{{reflist|refs=
<ref name=reid>{{cite journal|bibcode=2014ApJ...796....2R|arxiv=1409.2453|title=A Parallax Distance to the Microquasar GRS 1915+105 and a Revised Estimate of its Black Hole Mass|journal=The Astrophysical Journal|volume=796|page=2|last1=Reid|first1=M. J|last2=McClintock|first2=J. E|last3=Steiner|first3=J. F|last4=Steeghs|first4=D|last5=Remillard|first5=R. A|last6=Dhawan|first6=V|last7=Narayan|first7=R|year=2014|issue=1|doi=10.1088/0004-637X/796/1/2|s2cid=9800558}}</ref>
<ref name=nasa>{{cite press release | publisher=[[NASA]] | date=2009-03-25 | title=An Erratic Black Hole Regulates Itself | url=http://www.nasa.gov/mission_pages/chandra/multimedia/photo09-020.html | access-date=2009-04-16 | archive-date=2017-07-09 | archive-url=https://web.archive.org/web/20170709121105/https://www.nasa.gov/mission_pages/chandra/multimedia/photo09-020.html | url-status=dead }}</ref>
<ref name=cs1992>{{cite journal|bibcode=1992IAUC.5590....2C|title=Grs 1915+105|journal=IAU Circ|volume=5590|page=2|last1=Castro-Tirado|first1=A. J|last2=Brandt|first2=S|last3=Lund|first3=N|year=1992}}</ref>
<ref name=cs1996>{{cite journal|bibcode=1996ApJ...461L..99C|title=Infrared Spectroscopy of the Superluminal Galactic Source GRS 1915+105 During the September 1994 Outburst|journal=Astrophysical Journal Letters |volume=461|issue=2|pages=L99|last1=Castro-Tirado|first1=A. J|last2=Geballe|first2=T. R|last3=Lund|first3=N|year=1996|doi=10.1086/310009|s2cid=122041186 |doi-access=free}}</ref>
<ref name=Fenderetal>{{cite journal|bibcode=1999MNRAS.304..865F|title=MERLIN observations of relativistic ejections from GRS 1915+105|journal=Monthly Notices of the Royal Astronomical Society|volume=304|issue=4|page=865|last1=Fender|first1=R. P|last2=Garrington|first2=S. T|last3=McKay|first3=D. J|last4=Muxlow|first4=T. W. B|last5=Pooley|first5=G. G|last6=Spencer|first6=R. E|last7=Stirling|first7=A. M|last8=Waltman|first8=E. B|year=1999|doi=10.1046/j.1365-8711.1999.02364.x|doi-access=free |arxiv=astro-ph/9812150|s2cid=144364}}</ref>
<ref name=greiner>{{cite arXiv|eprint=astro-ph/0111540|last1=Greiner|first1=J.|title=GRS 1915+105|year=2001}}</ref>
<ref name="Neil">{{cite journal |last1=Neil |first1=Ethan T. |last2=Bailyn |first2=Charles D. |last3=Cobb |first3=Bethany E. |title=Infrared Monitoring of the Microquasar GRS 1915+105: Detection of Orbital and Superhump Signatures |journal=The Astrophysical Journal |date=March 2007 |volume=657 |issue=1 |pages=409–414 |doi=10.1086/510287 |arxiv=astro-ph/0610480 |bibcode=2007ApJ...657..409N |s2cid=15959057 |doi-access=free }}</ref>
<ref name="space-paper">{{cite journal|arxiv=astro-ph/0606076|doi=10.1086/508457|author=Jeffrey E. McClintock |author2=Rebecca Shafee |author3=Ramesh Narayan |author4=Ronald A. Remillard |author5=Shane W. Davis |author6=Li-Xin Li |title=The Spin of the Near-Extreme Kerr Black Hole GRS 1915+105|journal=[[Astrophysical Journal]]|year=2006|volume=652|issue=1|pages=518–539|bibcode=2006ApJ...652..518M|s2cid=1762307|url=https://iopscience.iop.org/article/10.1086/508457}}</ref>
<ref name=space>{{cite news|url=https://www.space.com/3141-pushing-limit-black-hole-spins-phenomenal-rate.html|title=Pushing the Limit: Black Hole Spins at Phenomenal Rate|work=space.com|access-date=2017-11-25|author=Jeanna Bryne}}</ref>
<ref name=mirabel>{{cite journal|doi=10.1038/371046a0|title=A superluminal source in the Galaxy|journal=Nature|volume=371|issue=6492|page=46|year=1994|last1=Mirabel|first1=I. F|last2=Rodríguez|first2=L. F|bibcode=1994Natur.371...46M|s2cid=4347263}}</ref>
<ref name=abubekerov>{{cite journal|bibcode=2006ARep...50..544A|title=The mass of the compact object in the low-mass X-ray binary 2S 0921-630|journal=Astronomy Reports|volume=50|issue=7|page=544|last1=Abubekerov|first1=M. K|last2=Antokhina|first2=E. A|last3=Cherepashchuk|first3=A. M|last4=Shimanskii|first4=V. V|year=2006|doi=10.1134/S1063772906070043|arxiv=1201.4689|s2cid=40984265}}</ref>
<ref name=liu>{{cite journal|bibcode=2007A&A...469..807L|title=A catalogue of low-mass X-ray binaries in the Galaxy, LMC, and SMC (Fourth edition)|journal=Astronomy and Astrophysics|volume=469|issue=2|page=807|last1=Liu|first1=Q. Z|last2=Van Paradijs|first2=J|last3=Van Den Heuvel|first3=E. P. J|year=2007|doi=10.1051/0004-6361:20077303|arxiv=0707.0544|s2cid=14673570}}</ref>
}}
==External links==
* [https://web.archive.org/web/20070828170539/http://www.eso.org/public/outreach/press-rel/pr-2001/pr-24-01.html A Very Massive Stellar Black Hole in the Milky Way Galaxy] November 28, 2001 (ESO)
* [http://aladin.u-strasbg.fr/AladinPreview?-c=19+15+11.6%2B10+56+44&ident=V*+V1487+Aql&submit=Aladin+previewer Image V1487 Aquilae]
* [http://www.portaldoastronomo.org/noticia.php?id=10 O maior buraco negro estelar da Via Láctea (The biggest stellar black hole of the Milky Way)] - in Portuguese.
* [https://web.archive.org/web/20080930025802/http://laserstars.org/news/GRS1915n105.html MICRO-QUASAR WITHIN OUR GALAXY]
* [http://www.isdc.unige.ch/integral/outreach/science The micro quasar GRS 1915+105] INTEGRAL Science Data Centre
{{Sky|19|15|11.6|+|10|56|44|40000}}
{{Stars of Aquila}}
{{DEFAULTSORT:GRS 1915+105}}
[[Category:X-ray binaries]]
[[Category:Aquila (constellation)]]
[[Category:Microquasars]]
[[Category:Objects with variable star designations|Aquilae, V1487]]
[[Category:K-type giants]]