V604 Aquilae or Nova Aquilae 1905 is a nova which was first observed in the constellation Aquila in 1905 with a maximum brightness of magnitude 7.6.[3] It was never bright enough to be seen with the naked eye. It was discovered by Williamina Fleming on a Harvard College Observatory photographic plate taken on August 31, 1905.[6] Examination of plates taken earlier indicates that peak brightness occurred in mid-August 1905.[7] The star's quiescent visual band brightness is 19.6.[5]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquila |
| Right ascension | 19h 02m 06.33s[2] |
| Declination | −04° 26′ 43.2″[2] |
| Apparent magnitude (V) | 7.6(blue) – 19.6(V)[3] |
| Astrometry | |
| Absolute magnitude (MV) | -8.3[4] |
| Characteristics | |
| Spectral type | pec(Nova)[3] |
| B−V color index | 0.3[5] |
| Variable type | NA[3] |
| Other designations | |
| Database references | |
| SIMBAD | data |
V604 Aquilae faded by 3 magnitudes in just 25 days, making it a "fast nova".[6] Detection of a faint nebula surrounding the star, with a radius of 0.4 arc minutes, was reported early in 1906.[8] In 1994, a photometric study detected brightness variations of up to ~0.45 magnitudes on timescales of about one hour.[9] An attempt to detect cool molecular gas surrounding the nova in 2015 was unsuccessful.[10]