Globular cluster in Coma Berenices
M53
Far out toward the edge of what our galaxy still holds, and made almost entirely of the light elements that existed before stars began manufacturing the rest. It resolves reluctantly — 200mm before anything at the edges breaks up.
It is around sixty thousand light-years out from the galactic centre — one of the more remote globulars still clearly ours — and it has a neighbour, NGC 5053, a degree away and even more sparse. The two appear to be interacting, with a thin bridge of stars between them, which would make them the only such pair in our galaxy.
- Catalogue
- M53
- Type
- Globular cluster
- Constellation
- Coma Berenices
- Distance
- 58,000 light-years
- Apparent magnitude
- 7.6
- Surface brightness
- 21.8 mag/□″
- Apparent size
- 13′
- Right ascension
- 13h 13m
- Declination
- +18.17°
- Found by
- Johann Elert Bode, 1775
Magnitude 7.6 sounds comfortable and is spread over 13′, which brings it down to 21.8 per square arcsecond — the number that actually decides whether there is anything to see. Why surface brightness is the number that matters.
Could you see it?
Straightforward with the naked eye from Bortle 1 or darker; with 10×50 binoculars from Bortle 5.
| Sky | Eye | 10×50 | 80mm | 130mm | 200mm |
|---|---|---|---|---|---|
| Bortle 1 21.9 mag/□″ | Easy | Easy | Easy | Easy | Easy |
| Bortle 2 21.7 mag/□″ | No | Easy | Easy | Easy | Easy |
| Bortle 3 21.4 mag/□″ | No | Easy | Easy | Easy | Easy |
| Bortle 4 20.9 mag/□″ | No | Easy | Easy | Easy | Easy |
| Bortle 5 20.3 mag/□″ | No | Easy | Easy | Easy | Easy |
| Bortle 6 19.3 mag/□″ | No | Challenge | Challenge | Challenge | Challenge |
| Bortle 7 18.6 mag/□″ | No | No | No | No | No |
| Bortle 8 18.1 mag/□″ | No | No | No | No | No |
| Bortle 9 17.8 mag/□″ | No | No | No | No | No |
At the eyepiece
A compact, evenly bright ball that stays stubbornly unresolved until about 200mm and even then only crumbles at the edges. Sits a degree from the much stranger NGC 5053, a globular so sparse it barely holds together — and the two in one session make the better visit.
When, and from where
Highest in the middle of the night in April. Passes overhead at 18°N and rises from everywhere except the far south — below 72°S it never clears the horizon.
| Latitude | Highest it gets | |
|---|---|---|
| 60°N Oslo, Anchorage | 48° | |
| 51°N London, Calgary | 57° | |
| 40°N New York, Madrid | 68° | |
| 30°N Cairo, Houston | 78° | |
| 0°N the equator | 72° | |
| 33°S Sydney, Cape Town | 39° |
Nearby in the sky
The whole catalogue →Nothing else in the catalogue is especially close; the nearest is 5.2° apart, which is a separate trip rather than a nudge of the tube. Everything below is measured from M53 itself, not from the middle of Coma Berenices.
- M64 Black Eye Galaxy 5.2° apart Coma Berenices · magnitude 8.5 · binoculars from Bortle 5 or darker
- M60 Galaxy 9.7° apart Virgo · magnitude 8.8 · binoculars from Bortle 5 or darker
- M91 Galaxy 9.7° apart Coma Berenices · magnitude 10.2 · binoculars from Bortle 3 or darker
- M59 Galaxy 9.9° apart Virgo · magnitude 9.6 · binoculars from Bortle 5 or darker
One of 110. Positions J2000; the sky is the final authority.