M1 — Crab Nebula
Supernova Remnant in Taurus
About
The Crab Nebula, the remnant of a supernova that Chinese and Japanese observers recorded in 1054, about 6,500 light-years away in Taurus. A neutron star at its centre spins about 30 times a second and powers the glow.
Imaging tips
- Only about 7′ across, so it needs a long focal length: 3,460–5,770 mm on APS-C. A shorter lens gives a small object in a large frame, best cropped.
- One Hα, SII and OIII set used 10-minute subs, about 3 hours in total, under a near-full Moon; the author still wanted more SII and OIII to sharpen the filaments.
- Narrowband is workable even from a Bortle 8/9 city: one imager stacked 144 subs of 30 s through a 7 nm Hα filter, about 1 h 12 min.
- Best around December; it stays below 62° altitude from 50°N.
Facts
- Size
- 7′ × 5′
- Magnitude
- 8.4
- Coordinates
- RA 5h 34.5m, Dec +22° 1′
- Framing, APS-C
- 3460–5770 mm
- Framing, full frame
- longer than 4000 mm
- Best months
- Dec
- Peak altitude
- 62° from 50°N, 77° from 35°N