M25
open cluster · Sagittarius · 4.6ᵐ
A bright binocular cluster with the Cepheid U Sagittarii inside — its brightness pulses on a 6.7-day cycle.
Notable facts
About the same apparent size as the full Moon.
In brief
Which constellation is M25 in?
M25 lies in Sagittarius.
Is M25 visible to the naked eye?
4.6ᵐ — visible to the naked eye (under dark skies).
When is the best time to observe M25?
Best observed in June.
Data
- RA / Dec (J2000)
- 18h 32m · −19° 15′
- Type
- open cluster
- Constellation
- Sagittarius
- How to observe
- 4.6ᵐ — visible to the naked eye (under dark skies)
- Angular size
- 32′
- Designation
- M25 · IC 4725
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° | 11° | 131° |
| +55° | 16° | 125° |
| +45° | 26° | 118° |
| +30° | 41° | 112° |
| 0° | 71° | 109° |
| −35° | 74° | 114° |
Geometric altitude at upper culmination, atmospheric refraction not included. Positive latitudes are in the northern hemisphere.
Culmination time by month
| Month | Culmination |
|---|---|
| January | 10:46 |
| February | 08:39 |
| March | 06:53 |
| April | 05:00 |
| May | 03:06 |
| June | 01:00 |
| July | 22:56 |
| August | 20:55 |
| September | 19:02 |
| October | 17:13 |
| November | 15:12 |
| December | 13:04 |
Upper culmination in local solar time — no time-zone or daylight-saving correction applied.