A spiral galaxy in Coma Berenices with tightly wound, symmetrical arms, seen at an angle so it looks long. It is one of the Virgo Cluster's spirals, and an active galaxy with a feeding black hole.
Galaxy in Coma Berenices. Magnitude 10.3.
Can you see it from Guyana?
From Georgetown (6.8° N) it climbs to 83° above the northern horizon at its highest; from Lethem (3.4° N), to 79° above the northern horizon. It is highest at midnight on the night of 28 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 8.1° north-west of Vindemiatrix.
10x50 binoculars: Just detectable in binoculars from a dark site, as a faint smudge. M91 is 0.8° to the east.
A small telescope (80 to 100 mm): A long oval twice as long as wide with a bright centre; M91 is 0.8° to the east.
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: 8.7′ × 4.4′, 28% of the Moon's width (the Moon is about 31′ wide).
Brightness: magnitude 10.3. Fainter than the faintest stars in Georgetown (4.3) and Lethem (6.0): binoculars or a telescope.
Distance: 60 million light-years. The light reaching your eye left it about 60 million years ago.
True size: 140,000 light-years across its catalogued outline; light crosses it in 140,000 years.
Its central black hole is estimated at about 100 million times the Sun's mass, and seems to drive outflows of gas from its centre.
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 44 published estimates by several methods (no two direct ones agree to combine): NED-D (NASA/IPAC Extragalactic Database, redshift-independent distances), median of 44 estimates: 17.10 Mpc, 14.08-20.91 Mpc (16th-84th percentile); e.g. 2016AJ....152...50T, 2014MNRAS.444..527S, 2013ApJ...771...88L; retrieved 2026-10-21. True size: the apparent size times the distance (apparent size: OpenNGC (Mattia Verga, CC BY-SA 4.0), commit 4e2398a2).
Photograph: ESA/Hubble & NASA, D. Thilker and the MAUVE-HST Team, CC BY 4.0, source.