M55 (NGC 6809)
Also known as M55 · M 55 · NGC 6809
M55 (NGC 6809) is a globular star cluster in the constellation Sagittarius, about 16,310 light-years from Earth.
Facts
| Type | Globular star cluster |
|---|---|
| Constellation | Sagittarius |
| Position (J2000) | 19h 39m 59s, −30° 57′ |
| Distance | 16,310 light-years (its light set off about 16,310 years ago) |
| Brightness | magnitude 6.49 (smaller is brighter; the faintest stars the eye sees are about 6) |
| Size on the sky | 19′ × 19′ (the full Moon is about 31′) |
| Filter | No filter (It shines in starlight of every colour, so a nebula filter would only dim it; a dark sky helps more.) |
| Studied in | 930 scientific papers (SIMBAD) |
When and how to see it
M55 (NGC 6809) is highest in the sky at midnight in July. From India (about 20° N) it climbs to about 39° above the horizon; from 50° N, to about 9°. To see it you need binoculars.
Heights are worked out for India and for 50° N. Set your location in Settings to see them for where you are.
For tonight's best time from your own town, the darkness and the Moon, open it on the map and see its "Tonight from your location" card.
More in Sagittarius
- Lagoon Nebula (M8)
- M18 (NGC 6613)
- M21 (NGC 6531)
- M23 (NGC 6494)
- Omega Nebula (M17)
- Sagittarius A*
- Sagittarius Cluster (M22)
- Trifid Nebula (M20)
Everything in Sagittarius · All 88 constellations · All sky objects
Data: SIMBAD (CDS, Strasbourg; the site's weekly copy) · OpenNGC · Data sources & credits