M39
open cluster · Cygnus · 4.6ᵐ
A Messier catalogue object — open cluster in Cygnus.
Notable facts
About 1 the apparent diameter of the Moon.
In brief
Which constellation is M39 in?
M39 lies in Cygnus.
Is M39 visible to the naked eye?
4.6ᵐ — visible to the naked eye (under dark skies).
When is the best time to observe M39?
Best observed in August.
Data
- RA / Dec (J2000)
- 21h 32m · +48° 26′
- Type
- open cluster
- Constellation
- Cygnus
- How to observe
- 4.6ᵐ — visible to the naked eye (under dark skies)
- Angular size
- 32′
- Designation
- M39 · NGC 7092
Observing tip
Best in binoculars or a telescope at low power, so the whole cluster fits in the field of view.
Altitude above the horizon by latitude
| Latitude | Maximum altitude | Rise azimuth |
|---|---|---|
| +60° | 78° · never sets | — |
| +55° | 83° · never sets | — |
| +45° | 87° · never sets | — |
| +30° | 72° | 30° |
| 0° | 42° | 42° |
| −35° | 7° | 24° |
Geometric altitude at upper culmination, atmospheric refraction not included. Positive latitudes are in the northern hemisphere.
Culmination time by month
| Month | Culmination |
|---|---|
| January | 13:47 |
| February | 11:39 |
| March | 09:54 |
| April | 08:01 |
| May | 06:06 |
| June | 04:00 |
| July | 01:56 |
| August | 23:55 |
| September | 22:02 |
| October | 20:14 |
| November | 18:13 |
| December | 16:04 |
Upper culmination in local solar time — no time-zone or daylight-saving correction applied.