When to photograph M 57 (Ring Nebula)
M 57, the Ring Nebula, is a planetary nebula in Lyra, 1′ across at magnitude 8.8. Also listed as NGC 6720.
When to photograph it
From 45° N the best months are August and September, with up to 5.5 hours of astronomical darkness above 30° in August. It reaches 78° at its highest.
From 35° S it never climbs above 30°. It peaks at 22° when it crosses the meridian, low enough that haze and light pollution soften it. It is possible with a clear northern horizon, but hard.
Framing
At 1′ it is small. Even 4000 mm of focal length leaves it filling less than a third of an APS-C frame, so it suits long focal lengths, small pixels and good seeing.
Filters and the moon
Planetary nebulae are bright in OIII and H-alpha and small, so narrowband works and the moon matters less. Short subs help with the bright core. The dark sky calendar shows which nights this month are moon-free where you are.
Plan it for tonight
Dates and times depend on your exact location. The imaging planner shows M 57's altitude through tonight, its transit time and its distance from the moon. For sub length, use the exposure calculator.
Nearby targets
- M 56 5.7° away
- NGC 6820 14.6° away
- NGC 6888 Crescent Nebula 16.8° away
- M 27 Dumbbell Nebula 17.8° away
- NGC 6882 18.2° away
- M 29 19.1° away
Gear that suits M 57
M 57 is only 1.3′ across, so it stays small in any amateur telescope. The longest focal length gives it the most pixels. It shines in H-alpha and OIII, so a dual-band filter on a color camera cuts through light pollution and moonlight.
- Celestron C8 OTA 2032 mm f/10: fills 5% of an APS-C frame's short side View at High Point Scientific
- Optolong L-Ultimate 3 nm 3 nm dual-band, Ha, OIII, for color cameras View at High Point Scientific
- Antlia ALP-T 5 nm 5 nm dual-band, Ha, OIII, for color cameras View at High Point Scientific
Retailer links are affiliate links. If you buy through one, the site may earn a commission at no extra cost to you. Details