| NGC 7840 | |
|---|---|
 SDSS image of NGC 7840 | |
| Observation data (J2000 epoch) | |
| Constellation | Pisces[1][2] |
| Right ascension | 00h 07m 08.79s[3] |
| Declination | +08° 22′ 59.6″[3] |
| Apparent magnitude (V) | 15[1] |
| Characteristics | |
| Type | S?[1] |
| Apparent size (V) | 0.676′ × 0.457′ |
| Other designations | |
| 2MASX J00070878+0822598, PGC 1345780[3] | |
NGC 7840, the last numerical entry in the New General Catalogue, is an unbarred spiral galaxy in the constellation Pisces.[1] Its velocity with respect to the cosmic microwave background is 10906 ± 49 km/s, which corresponds to a Hubble distance of 160.85 ± 11.30 Mpc (∼524 million light-years), and its diameter is about 162,000 light-years.[4] It was discovered by German astronomer Albert Marth on 29 November 1864.[1]
For observing from Earth's surface, it has a magnitude of 15.5 in the early 21st century.[5] One observing guide recommended a telescope with a least 300mm aperture for observations.[5]
- ^ a b c d e Celestial Atlas, "NGC Object 7840", Courtney Seligman, March 2010 (accessed 2010-10-27)
- ^ WikiSky, "NGC 7840" (accessed 2010-10-17)
- ^ a b c "Search specification: NGC 7840". HyperLeda. Université Claude Bernard Lyon 1. Retrieved 2021-02-12.
- ^ "NASA/IPAC Extragalactic Database". Results for NGC 7840. Retrieved 3 August 2024.
- ^ a b Bakich, Michael E. (2010-07-10). 1,001 Celestial Wonders to See Before You Die: The Best Sky Objects for Star Gazers. Springer Science & Business Media. ISBN 9781441917775.