Key facts
- Constellation
- Pisces
- Right ascension
- 01 39 37.8
- Declination
- 07 ° 14 ′ 14 ″
- Redshift
- +0.010547 ± 0.000007
- Heliocentric radial velocity
- 3,162 km/s
- Distance
- 42.24 ± 2.97 Mpc (137.8 ± 9.7 Mly )
- Surface brightness
- 12.81 mag/am
- Type
- Barred spiral galaxy
- Size
- 47,200 ly (24.48 kpc )
- Apparent size v
- 0.8 arcminites × 0.5 arcminites
via Wikipedia infobox
~1 min read
Encyclopedic overview
NGC 638 is a barred spiral galaxy located in the constellation of Pisces. Its velocity speed to the cosmic microwave background is 2,864± 21 km/s, which corresponds to a Hubble's law of 42.2 ± 3.0 Mpc (~138 million light-year). NGC 638 was discovered by American astronomer Lewis A. Swift in 1886.
NGC 638 has a broad Hydrogen line. NGC 638 is a galaxy whose nucleus shines in the ultraviolet domain. It is listed in the Markarian catalogue under the code Mrk 1003 (MK 1003).
Excerpted from Wikipedia’s “NGC 638” article, available under the CC BY-SA 4.0 licence.