Arp242 — Mice Galaxies
Galaxy in Coma Berenices
About
NGC 4676, the Mice, two spiral galaxies in Coma Berenices that have started to merge, about 345 million light-years away. Tidal forces have pulled out the long tails behind them, and both belong to the Coma Cluster. Arp listed it among galaxies with the appearance of fission.
Imaging tips
- Only about 2′ across, so it is too small to frame: use a long focal length and a fine pixel scale.
- Faint at 22.9 mag/arcsec², and galaxies need broadband. One imager gathered 10 h 15 min of L, R, G and B, with the most time in red.
- That image was built from one long exposure per channel, from 65 minutes of luminance up to 215 minutes of red.
- Best around March and April; it peaks near 71° altitude from 50°N.
Facts
- Size
- 2′ × 1′
- Magnitude
- 13.5
- Coordinates
- RA 12h 46.1m, Dec +30° 44′
- Framing, APS-C
- longer than 4000 mm
- Framing, full frame
- longer than 4000 mm
- Best months
- Mar, Apr
- Peak altitude
- 71° from 50°N, 86° from 35°N