NGC 4993
| NGC 4993 | |
|---|---|
 NGC 4993 and GRB 170817A afterglow. | |
| Observation data | |
| Constellation | Hydra |
| Right ascension | 13h 09m 47.2s |
| Declination | −23° 23′ 4″ |
| Apparent magnitude (V) | 12.4[1] |
| Characteristics | |
| Type | E/S0 |
NGC 4993 (also catalogued as NGC 4994) is an elliptical galaxy in the constellation Hydra, discovered in 1789 by William Herschel.[2] In August 2017, astronomers reported[3] that the short gamma-ray burst GRB 170817A, of the sort conjectured to be emitted in the collision of two neutron stars,[4] was detected in this galaxy.
On 16 October 2017, the team officially announced the detection of a gravitational wave, named GW170817, associated with the merger of two neutron stars.[5][6][7][8] A gravitational wave event associated with this burst provided direct confirmation that binary neutron star collisions produce short gamma-ray bursts.[9]
Observations
GRB 170817A is a gamma-ray burst (GRB) detected by NASA's Fermi and ESA's INTEGRAL on 17 August 2017.[10][3][11][12]
GW170817 was a gravitational wave signal observed by the LIGO/Virgo collaboration on 17 August 2017, and was the first gravitational wave event that was observed to have a simultaneous electromagnetic signal.[13][6] The gravitational wave signal, which had a duration of about 100 seconds, is the first gravitational wave detection of the merger of two neutron stars, and was associated with GRB 170817A.[14][8][7]
See also
- Gravitational-wave astronomy
- List of gamma ray bursts
- List of gravitational wave observations
- Swift Gamma-Ray Burst Mission
- Ultra-Fast Flash Observatory Pathfinder
References
- ^ Staff (2017). "Galaxy NGC 4993 - Galaxy in Hydra Constellation". dso-browser.com }. Retrieved 30 September 2017.
- ^ "NGC 4993". Deep Sky Observer's Companion. Retrieved 28 August 2017.
- ^ a b Drake, Nadia (25 August 2017). "Strange Stars Caught Wrinkling Spacetime? Get the Facts". National Geographic. Retrieved 27 August 2017.
- ^ Nakar, E. (2007). "Short-hard gamma-ray bursts". Physics Reports. 442: 166–236. arXiv:astro-ph/0701748. Bibcode:2007PhR...442..166N. doi:10.1016/j.physrep.2007.02.005.
- ^ Abbott, B. P.; et al. (16 October 2017). "GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral". Physical Review Letters. 119 (16). doi:10.1103/PhysRevLett.119.161101.
{{cite journal}}: Explicit use of et al. in:|first1=(help) - ^ a b Landau, Elizabeth; Chou, Felicia; Washington, Dewayne; Porter, Molly (16 October 2017). "NASA Missions Catch First Light from a Gravitational-Wave Event". NASA. Retrieved 16 October 2017.
- ^ a b Cho, Adrian (16 October 2017). "Merging neutron stars generate gravitational waves and a celestial light show". Science (magazine). Retrieved 16 October 2017.
- ^ a b Krieger, Lisa M. (16 October 2017). "A Bright Light Seen Across The Universe, Proving Einstein Right - Violent collisions source of our gold, silver". The Mercury News. Retrieved 16 October 2017.
- ^ Overbye, Dennis (16 October 2017). "LIGO Detects Fierce Collision of Neutron Stars for the First Time". The New York Times. ISSN 0362-4331. Retrieved 16 October 2017.
{{cite news}}: Cite has empty unknown parameter:|dead-url=(help) - ^ Kienlin, Andreas von (17 August 2017). "GCN Circular; Number: 21520; GRB 170817A: Fermi GBM detection; 2017/08/17 20:00:07 GMT". Max Planck Institute for Extraterrestrial Physics. Retrieved 28 August 2017.
- ^ Castelvecchi, Davide (25 August 2017). "Rumours swell over new kind of gravitational-wave sighting". Nature News. doi:10.1038/nature.2017.22482. Retrieved 27 August 2017.
- ^ Sokol, Joshua (25 August 2017). "What Happens When Two Neutron Stars Collide?". Wired. Retrieved 28 August 2017.
- ^ Abbott, B. P.; et al. (LIGO Scientific Collaboration & Virgo Collaboration) (16 October 2017). "GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral". Physical Review Letters. 119 (16). doi:10.1103/PhysRevLett.119.161101.
- ^ Overbye, Dennis (16 October 2017). "LIGO Detects Fierce Collision of Neutron Stars for the First Time". The New York Times. Retrieved 16 October 2017.
External links
- "NGC 4993". SIMBAD. Retrieved 28 August 2017.
{{cite web}}: Cite has empty unknown parameters:|trans_title=,|day=,|month=, and|deadurl=(help) - "NGC 4993". DSO Browser. Retrieved 28 August 2017.
{{cite web}}: Cite has empty unknown parameters:|trans_title=,|day=,|month=, and|deadurl=(help) - Courtney Seligman. "New General Catalog Objects: NGC 4950 – 4999". Retrieved 28 August 2017.
{{cite web}}: Cite has empty unknown parameters:|trans_title=,|day=,|month=, and|deadurl=(help) - Hartmut Frommert. "Revised NGC Data for NGC 4993". SEDS. Retrieved 28 August 2017.
{{cite web}}: Cite has empty unknown parameters:|trans_title=,|day=,|month=, and|deadurl=(help) - GRB 170817A – NASA/IPAC Extragalactic Database (NED)
- GRB 170817A – Max Planck Institute for Extraterrestrial Physics (MPE)
- GRB 170817A - INTEGRAL Science Data Center (ISDC)
- [Starmap]
- NGC 4993 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images