Sh2-224
Supernova Remnant in Auriga
About
A faint supernova remnant in Auriga, about 14,700 light-years away and roughly 163 light-years across. A round section and a triangular section sit side by side, which has earned it the nickname Rice Hat Nebula.
Imaging tips
- Its glow is mostly hydrogen-alpha with some OIII, so use narrowband; one team adds a little RGB only to give the stars natural colour.
- One team shot 10-minute Hα and OIII subs through a 655 mm refractor for about 47 hours, and suggests at least 15 hours, ideally 50 to 60.
- A source gives the remnant as about 30′ × 17.5′, so a field of about 1° suits it; a faint, line-shaped arc to the west is thought to be a bow shock.
- Best in November and December, when it climbs to about 83° altitude from 50°N.
Facts
- Size
- 25′
- Magnitude
- —
- Coordinates
- RA 5h 27.3m, Dec +42° 58′
- Framing, APS-C
- 970–1620 mm
- Framing, full frame
- 1490–2480 mm
- Best months
- Nov, Dec
- Peak altitude
- 83° from 50°N, 82° from 35°N