Arp281
Galaxy in Canes Venatici
About
An edge-on barred spiral in Canes Venatici, about 30 million light-years away, seen as a wedge-shaped streak. A starburst at its centre produces many supernovae, whose winds push gas out of the disk and into a hot halo seen in X-rays. Arp listed it with NGC 4627 among double galaxies.
Imaging tips
- At 1510–2520 mm on APS-C the galaxy spans a good part of the frame, which is roughly 35′ across at that range.
- Surface brightness is about 21.9 mag/arcsec², so it is not extremely faint; one imager used a one-shot colour camera, with no filters, for about 3 hours of 5-minute subs.
- The Hockey Stick galaxies and the dwarf elliptical NGC 4627 share a wide field with it, so a short focal length can frame them together.
- Gradients from city light pollution and moonlight were the main trouble for one imager; a mask lets you stretch the galaxy without bloating the stars.
- Best around March and April; it climbs to about 72° from 50°N.
Facts
- Size
- 14.5′ × 2.2′
- Magnitude
- 9.2
- Coordinates
- RA 12h 42.1m, Dec +32° 33′
- Framing, APS-C
- 1670–2790 mm
- Framing, full frame
- 2560–4270 mm
- Best months
- Mar, Apr
- Peak altitude
- 73° from 50°N, 88° from 35°N