| 3C 454.3 | |
|---|---|
Fermi-LAT gamma-ray image, including 3C 454.3
| |
| Observation data (Epoch J2000) | |
| Constellation | Pegasus |
| Right ascension | 22h53m 57.7s[1] |
| Declination | +16° 08′ 53.6″[1] |
| Redshift | 0.859001 ± 0.000170[1] |
| Distance | 7.7 Gly |
| Type | Blazar/Quasar |
| Apparent magnitude (V) | 16.1[1] |
| See also: Quasar, List of quasars | |
3C 454.3 is a blazar (a type of quasar with a jet oriented toward Earth) located away from the galactic plane. It is one of the brightest gamma ray sources in the sky,[2] and is one of the most luminous astronomical object ever observed, with a maximum absolute magnitude of -31.4.[3] It has the brightest blazar gamma ray flare recorded, twice as bright as the Vela Pulsar in the Milky Way galaxy. It also flares at radio and visible wavelengths – in red light, the blazar brightened by more than 2.5 times to magnitude 13.7 – and it is very bright at high radio frequencies.[4]
It appears in Pegasus, near Alpha Pegasi (Markab). It has been known to occasionally outburst, brightening to a peak apparent magnitude of 13.4 in June 2014.[5][6]
In July and August 2007, the gamma-ray blazar 3C 454.3 flared to near-historic levels, only two years after its record-breaking 2005 optical flare. Luckily, Spitzer Space Telescope and Chandra X-ray Observatory were already scheduled for simultaneous observations. Swift, RXTE and the new gamma-ray AGILE spacecraft responded to this target of opportunity, and were joined by observatories around the world.
The Fermi Large Area Telescope AGN science group started a multiwavelength campaign for blazar 3C454.3 (2251+158), in July and continuing through August 2007. This Ad Hoc Intensive Campaign (AIC) was prompted by brightening in the radio, optical and X-ray.
