3C 66A is a blazar[1][2] located in the constellation Andromeda.
3C 66A | |
---|---|
Observation data (Epoch J2000) | |
Constellation | Andromeda |
Right ascension | 02h 22m 39.612s[1] |
Declination | +43° 02′ 07.80″[1] |
Redshift | 0.444[1][2] |
Distance | 4.5 billion light-years (Light travel time)[2] 5.4 billion light-years (present)[2] |
Type | BLLAC[2] |
Apparent magnitude (V) | 15.5[1][2] |
Other designations | |
2E 558, 2EG J0220+4228, B3 0219+428A, QSO B0219+4248[1] | |
See also: Quasar, List of quasars |
The "distance" of a far away galaxy depends on the distance measurement used. With a redshift of 0.444,[1][2] light from this active galaxy is estimated to have taken around 4.5 billion years to reach Earth.[2] But as a result of the expansion of the Universe, the present (co-moving) distance to this galaxy is about 5.4 billion light-years (1647 Mpc).[2] Even at this great distance this blazar has an apparent magnitude of about 15.5.[1] Although 0.444 is used as the common redshift value, 0.3347 is a new strict lower limit "inferred through observing the far-UV absorption by the low-z IGM."[3]
3C 66A underwent an optical outburst in 2007 August, as monitored by the Tuorla blazar monitoring program.[4] The event was monitored by the Whole Earth Blazar Telescope project.