M90 (Galaxy)
A large spiral galaxy in Virgo whose outer disc has lost its gas: passing near the cluster's centre stripped it away, so only the inner disc still forms stars.
Galaxy in Virgo. Magnitude 9.5.
Can you see it from Guyana?
From Georgetown (6.8° N) it climbs to 84° above the northern horizon at its highest; from Lethem (3.4° N), to 80° above the northern horizon. It is highest at midnight on the night of 29 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 6.6° west of Vindemiatrix.
- 10x50 binoculars: Just detectable in binoculars from a dark site, as a faint smudge. M89 is 0.7° away.
- A small telescope (80 to 100 mm): A long oval, 2.4 times as long as wide, with a bright core; M89 is 0.7° to the south-west.
- 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: 9.1′ × 3.8′, 29% of the Moon's width (the Moon is about 31′ wide).
- Brightness: magnitude 9.5. 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: 99,000 light-years across its catalogued outline; light crosses it in 99,000 years.
Apparent size from OpenNGC (Mattia Verga), CC-BY-SA-4.0.
What it is made of
- Type
- Spiral galaxy
- Notable
- About 300 million years ago its orbit took it near the cluster's centre, where the dense gas stripped much of its own; it now forms stars only in its inner disc.
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: 11.45 Mpc, 9.33-16.56 Mpc (16th-84th percentile); e.g. 2014ApJ...782....4K, 2008ApJ...683...78C, 2000A&A...355..835E; 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: M89 (Galaxy) · M91 (Galaxy) · M58 (Galaxy) · Virgo Galaxy (M87) · M88 (Galaxy) · M59 (Galaxy)