M61 (Galaxy)
One of the larger spirals of the Virgo Cluster, face-on, and the southernmost Virgo galaxy on Messier's list. Its distance is unsettled: a supernova in it gives nearly twice what the Tully-Fisher method does.
Galaxy in Virgo. Magnitude 10.2.
Can you see it from Guyana?
From Georgetown (6.8° N) it climbs to 88°, almost straight overhead at its highest; from Lethem (3.4° N), to 89°, almost straight overhead. It is highest at midnight on the night of 25 Mar, in the middle of its season. The page works out tonight's rise, highest point and set for both towns in Guyana time (UTC-4), and where the Moon is.
What you'll see
- Your eyes: Not visible to the eye. It lies 7.7° north-west of Porrima.
- 10x50 binoculars: Just detectable in binoculars from a dark site, as a faint smudge.
- A small telescope (80 to 100 mm): A round, faint glow with a brighter middle; its arms need a larger telescope and a dark sky.
- A camera: Tiny on camera: it needs 2,000 mm or more of focal length on a tracking mount.
How big, how bright, how far
- Size on the sky: 6.9′ × 6.6′, 22% of the Moon's width (the Moon is about 31′ wide).
- Brightness: magnitude 10.2. Fainter than the faintest stars in Georgetown (4.3) and Lethem (6.0): binoculars or a telescope.
- Distance: 40 million light-years. The light reaching your eye left it about 40 million years ago.
- True size: 80,000 light-years across its catalogued outline; light crosses it in 80,000 years.
Apparent size from OpenNGC (Mattia Verga), CC-BY-SA-4.0.
What it is made of
- Type
- Spiral galaxy, seen face-on
- Notable
- Its distance estimates disagree: a type II supernova in it gives 18.7 Mpc, the Tully-Fisher relation 9.6 Mpc.
What is in it, not measured:
- Stars: an older central bulge and a disc of younger stars
- Gas and dust: in the spiral arms, where new stars form
- Dark matter: inferred from how fast it spins
How we know: Distance from the median of 14 published estimates by several methods (no two direct ones agree to combine): NED-D (NASA/IPAC Extragalactic Database, redshift-independent distances), median of 14 estimates: 12.25 Mpc, 9.16-19.25 Mpc (16th-84th percentile); e.g. 2015ApJ...799..215P, 2014ApJ...782...98B, 2014AJ....148..107R; retrieved 2026-10-21. True size: the apparent size times the distance (apparent size: OpenNGC (Mattia Verga, CC BY-SA 4.0), commit 4e2398a2).
More deep-sky objects: M49 (Galaxy) · Virgo Galaxy (M87) · M58 (Galaxy) · M84 (Galaxy) · M86 (Galaxy) · M59 (Galaxy)