Globular cluster in Ophiuchus
M14
In 1964 Amelia Wehlau found a nova on plates of this cluster that Helen Sawyer Hogg had taken in 1938 — the first nova in a globular ever caught on a photograph, and it had sat there unnoticed for twenty-six years. The cluster itself is dust-dimmed and stays granular in most amateur instruments.
It is around a hundred and fifty light-years across and sits behind enough dust to cost it the better part of a magnitude, which is why a cluster this size stays stubbornly grainy rather than resolving. The nova Wehlau found had reached about magnitude 16 in 1938 and nobody had been looking.
- Catalogue
- M14
- Type
- Globular cluster
- Constellation
- Ophiuchus
- Distance
- 30,300 light-years
- Apparent magnitude
- 7.6
- Surface brightness
- 21.4 mag/□″
- Apparent size
- 11′
- Right ascension
- 17h 38m
- Declination
- −3.25°
- Found by
- Charles Messier, 1764
Small enough that its 7.6 magnitudes arrive concentrated rather than smeared: 21.4 per square arcsecond, which is why it stands out from the sky better than its brightness alone suggests. 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 modest, evenly lit ball that resolves grudgingly and only at the edges under 250mm. It is the least visually rewarding of the Ophiuchus globulars and the most interesting historically, which is a combination this catalogue offers more than once.
When, and from where
Highest in the middle of the night in June. Close enough to the celestial equator to rise from almost anywhere on Earth, and to pass overhead for anyone near 3°S.
| Latitude | Highest it gets | |
|---|---|---|
| 60°N Oslo, Anchorage | 27° | |
| 51°N London, Calgary | 36° | |
| 40°N New York, Madrid | 47° | |
| 30°N Cairo, Houston | 57° | |
| 0°N the equator | 87° | |
| 33°S Sydney, Cape Town | 60° |
Nearby in the sky
The whole catalogue →Nothing else in the catalogue is especially close; the nearest is 10° apart, which is a separate trip rather than a nudge of the tube. Everything below is measured from M14 itself, not from the middle of Ophiuchus.
- M10 Globular cluster 10° apart Ophiuchus · magnitude 6.6 · binoculars from Bortle 5 or darker
- M12 Globular cluster 13° apart Ophiuchus · magnitude 6.7 · binoculars from Bortle 5 or darker
- M16 Eagle Nebula 15° apart Serpens · magnitude 6.0 · binoculars from Bortle 2 or darker
- M9 Globular cluster 16° apart Ophiuchus · magnitude 7.7 · binoculars from Bortle 5 or darker
One of 110. Positions J2000; the sky is the final authority.