M65 — Leo Triplet (member)
Galaxy in Leo
About
NGC 3623, an intermediate spiral galaxy in Leo about 41 million light-years away, seen at a steep angle. It forms the Leo Triplet with M66 and NGC 3628, and the Type II supernova SN 2013am went off in it in 2013.
Imaging tips
- Roughly 10′ by 3′: 2,420–4,040 mm on APS-C or 3,710–6,190 mm on full frame frames M65 alone, while a 500–800 mm scope takes in the whole triplet.
- Broadband suits the triplet: the Galactic Hunter write-up found Hα added little, and its frames ran 10 minutes in LRGB and 3 minutes on a DSLR.
- Faint at 21.6 mag/arcsec². One LRGB set reached 12.5 hours; a DSLR set on an 8-inch Newtonian reached about 3.5 hours.
- That write-up lost time removing reflections from bright stars just beyond its frame, and blamed telescope tilt, so check tilt before a wide field.
- Best around February and March; it stays below 53° altitude from 50°N.
Facts
- Size
- 10′ × 3′
- Magnitude
- 9.3
- Coordinates
- RA 11h 18.9m, Dec +13° 6′
- Framing, APS-C
- 2420–4040 mm
- Framing, full frame
- 3710–6190 mm
- Best months
- Feb, Mar
- Peak altitude
- 53° from 50°N, 68° from 35°N