Butterfly Cluster
open cluster · Scorpius · 4.2ᵐ
The Butterfly Cluster — its chains of stars really do trace a shape with open wings.
Notable facts
About 1/2 the apparent diameter of the Moon.
In brief
Which constellation is Butterfly Cluster in?
Butterfly Cluster lies in Scorpius.
Is Butterfly Cluster visible to the naked eye?
4.2ᵐ — visible to the naked eye (under dark skies).
When is the best time to observe Butterfly Cluster?
Best observed in June.
Data
- RA / Dec (J2000)
- 17h 40m · −32° 13′
- Type
- open cluster
- Constellation
- Scorpius
- How to observe
- 4.2ᵐ — visible to the naked eye (under dark skies)
- Angular size
- 15′
- Designation
- M6 · NGC 6405 · Butterfly Cluster
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° | never rises | — |
| +55° | 3° | 158° |
| +45° | 13° | 139° |
| +30° | 28° | 128° |
| 0° | 58° | 122° |
| −35° | 87° | 131° |
Geometric altitude at upper culmination, atmospheric refraction not included. Positive latitudes are in the northern hemisphere.
Culmination time by month
| Month | Culmination |
|---|---|
| January | 09:55 |
| February | 07:47 |
| March | 06:02 |
| April | 04:09 |
| May | 02:14 |
| June | 00:08 |
| July | 22:04 |
| August | 20:03 |
| September | 18:10 |
| October | 16:21 |
| November | 14:21 |
| December | 12:12 |
Upper culmination in local solar time — no time-zone or daylight-saving correction applied.