NGC 4993
Galaxy NGC 4993 |
|
---|---|
NGC 4993 with gamma-ray flash GRB 170817A | |
AladinLite | |
Constellation | Water snake |
Position equinox : J2000.0 , epoch : J2000.0 |
|
Right ascension | 13 h 09 m 47.7 s |
declination | -23 ° 23 ′ 02 ″ |
Appearance | |
Morphological type | (R ') SAB (rs) 0- |
Brightness (visual) | 12.4 mag |
Brightness (B-band) | 13.4 mag |
Angular expansion | 1.3 ′ × 1.1 ′ |
Position angle | 168 ° |
Surface brightness | 12.9 mag / arcmin² |
Physical data | |
Affiliation | LGG 332 |
Redshift | 0.009727 +/- 0.000050 |
Radial velocity | 2916 +/- 15 km / s |
Stroke distance v rad / H 0 |
(124 ± 9) · 10 6 ly (38.1 ± 2.7) Mpc |
history | |
discovery | Wilhelm Herschel John Herschel |
Discovery date | March 26, 1789 March 25, 1836 |
Catalog names | |
NGC 4993, 4994 • PGC 45657 • ESO 508-G018 • MCG -04-31-039 • 2MASX J13094770-2323017 • SGC 130705-2307.1 • GC 3428, 3429 • H III 766 • h 3471 • AM 1307-230 • LDCE 0955 NED007 |
NGC 4993 = NGC 4994 is an elliptical galaxy in the constellation of the Water Snake . Estimates of the distance using various methods give results in the range of around 130 million light years . On August 17, 2017, a gravitational wave burst with a simultaneous gamma ray burst was discovered in this galaxy .
Observations
On August 17, 2017, a gravitational wave signal ( GW170817 ) and a gamma-ray burst ( GRB170817A ) were observed in coincidence, the origin of which was in this galaxy. The observation can be explained by the collision of two neutron stars ( kilonova ), which generally suggests such events as (a) cause of GRBs.
Discovery story
The galaxy was discovered twice; first on March 26, 1789 by Wilhelm Herschel with an 18.7-inch reflecting telescope, who described it as “vF, vS” (observation listed as NGC 4993 ); then on March 25, 1836 by John Herschel , who "pF, R, slbM, 35 arcseconds. Among stars ”(listed as NGC 4994 ).
Web links
- NGC 4993. SIMBAD, accessed February 24, 2015 .
- NGC 4993. DSO Browser, accessed February 24, 2015 .
- ESO: ESO telescopes observe first light from a gravitational wave source + photos
Individual evidence
- ↑ a b c d NASA / IPAC EXTRAGALACTIC DATABASE
- ↑ a b c d e f SEDS : NGC 4993
- ↑ Nadia Drake: Strange Stars Caught Wrinkling Spacetime? Get the facts. . In: National Geographic . August 25, 2017. Retrieved August 27, 2017.
- ↑ B. P. et al Abbott: GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral . In: Physical Review Letters . 119, No. 16, October 16, 2017. doi : 10.1103 / PhysRevLett.119.161101 .
- ^ NASA Missions Catch First Light from a Gravitational-Wave Event . In: NASA , October 16, 2017.
- ^ Adrian Cho: Merging neutron stars generate gravitational waves and a celestial light show . In: Science , October 16, 2017.
- ↑ Lisa M. Krieger: A Bright Light Seen Across The Universe, Proving Einstein Right - Violent collisions source of our gold, silver . In: The Mercury News , October 16, 2017.
- ^ Andreas von Kienlin: GCN Circular; Number: 21520; GRB 170817A: Fermi GBM detection; 2017/08/17 20:00:07 GMT . In: Max Planck Institute for Extraterrestrial Physics . August 17, 2017. Retrieved August 28, 2017.
- ↑ Davide Castelvecchi: Rumors swell over new kind of gravitational-wave sighting , Nature News . August 25, 2017. Accessed August 27, 2017.
- ↑ Joshua Sokol: What Happens When Two Neutron Stars Collide? . In: Wired . August 25, 2017. Retrieved August 28, 2017.
- ↑ Dennis Overbye: LIGO Detects Fierce Collision of Neutron Stars for the First Time (en-US) . In: The New York Times , October 16, 2017.
- ^ Matthew Wright: Neutron star merger directly observed for the first time , on: EurekAlert! (University of Maryland)
- ↑ Marlene Weiß: Astronomers observe the origin of gravitational waves for the first time , on: Süddeutsche.de from October 16, 2017
- ↑ dpa: Gravitational waves from colliding neutron stars recorded on: Hessische Niedersächsische Allgemeine (HNA) from October 16, 2017, as well as: Gravitational waves from colliding neutron stars recorded on: Süddeutsche.de from October 16, 2017
- ↑ Robert Gast: Neutron star crash causes space-time to tremble , on: Spektrum.de from October 16, 2017
- ↑ First gravitational waves from neutron star collision ( Memento of the original from October 18, 2017 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , to: scinexx
- ↑ Auke Slotegraaf: NGC 4993. Deep Sky Observer's Companion, accessed on February 24, 2015 (English).
- ↑ Auke Slotegraaf: NGC 4994. Deep Sky Observer's Companion, accessed on February 24, 2015 (English).
- ↑ Seligman