Arp299
Galaxy in Ursa Major
About
Two galaxies in Ursa Major, NGC 3690 and IC 694, caught mid-collision roughly 134 million light-years from us. Arp placed it among the "Unclassified double galaxies". Since 1992 it has produced fifteen observed supernovae, twelve of them in NGC 3690.
Imaging tips
- Sources give about 2.4′ × 1.9′, so it is too small to frame: use a long focal length and a fine pixel scale.
- Surface brightness is 22.5 mag/arcsec², so plan many hours of broadband data; one imager gathered roughly 18 hours across 2021 and 2024 on an 8-inch f/10 from a Bortle 6/7 site.
- In that imager's result the pair is clearly resolved, while the faint vertical tidal tail is only just visible; supernova SN 2023wrk also showed in the frame.
- Best around February and March; it peaks near 81° altitude from 50°N.
Facts
- Size
- 3′ × 2′
- Magnitude
- 11.9
- Coordinates
- RA 11h 28.5m, Dec +58° 34′
- Framing, APS-C
- longer than 4000 mm
- Framing, full frame
- longer than 4000 mm
- Best months
- Feb, Mar
- Peak altitude
- 81° from 50°N, 66° from 35°N