H-NGC3992
Galaxy in Ursa Major
About
A barred spiral galaxy in Ursa Major, about 67 million light-years away, and the most distant object in the Messier catalogue. Also NGC 3992, it is the brightest member of a group that may hold over 50 galaxies. SN 1956A, a Type Ia supernova, appeared in it. It is also in the Herschel 400 list.
Imaging tips
- About 8′ × 5′: 3,030–5,050 mm on APS-C, so a long focal length suits it.
- Faint for its size at 22.4 mag/arcsec²; a galaxy needs broadband. One 980 mm refractor image used about 3 hours of LRGB with 5-minute subs, and another about 2 hours of 10-minute subs.
- Radio data show a central hole in the hydrogen inside its bar, so the bar and spiral arms are the structures to capture.
- Small companions UGC 6923, UGC 6940 and UGC 6969 are known, and a wide shot with Phecda shows NGC 3953 as well. Best around March and April.
Facts
- Size
- 8′ × 5′
- Magnitude
- 9.8
- Coordinates
- RA 11h 57.6m, Dec +53° 23′
- Framing, APS-C
- 3030–5050 mm
- Framing, full frame
- longer than 4000 mm
- Best months
- Mar, Apr
- Peak altitude
- 87° from 50°N, 72° from 35°N