M18
open cluster · Sagittarius · 6.9ᵐ
A Messier catalogue object — open cluster in Sagittarius.
Notable facts
About 1/3 the apparent diameter of the Moon.
In brief
Which constellation is M18 in?
M18 lies in Sagittarius.
Is M18 visible to the naked eye?
6.9ᵐ — visible with binoculars.
When is the best time to observe M18?
Best observed in June.
Data
- RA / Dec (J2000)
- 18h 20m · −17° 08′
- Type
- open cluster
- Constellation
- Sagittarius
- How to observe
- 6.9ᵐ — visible with binoculars
- Angular size
- 9′
- Designation
- M18 · NGC 6613
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° | 13° | 126° |
| +55° | 18° | 121° |
| +45° | 28° | 115° |
| +30° | 43° | 110° |
| 0° | 73° | 107° |
| −35° | 72° | 111° |
Geometric altitude at upper culmination, atmospheric refraction not included. Positive latitudes are in the northern hemisphere.
Culmination time by month
| Month | Culmination |
|---|---|
| January | 10:34 |
| February | 08:27 |
| March | 06:42 |
| April | 04:48 |
| May | 02:54 |
| June | 00:48 |
| July | 22:44 |
| August | 20:43 |
| September | 18:50 |
| October | 17:01 |
| November | 15:01 |
| December | 12:52 |
Upper culmination in local solar time — no time-zone or daylight-saving correction applied.