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Salt-and-Pepper Cluster (M37)
open cluster in Auriga
M37 is the richest of the three Auriga open clusters, with thousands of faint stars giving it a salt-and-pepper look. A single orange giant stands out near its center.
Save your telescope or lens on the planner to lay your camera frame over this diagram.
// Key facts
- Catalog
- M37
- Type
- open cluster
- Constellation
- Auriga
- Size
- 24′ across
- Brightness
- Magnitude 5.6
- Distance
- about 4,500 light-years
- Peak month (any location)
- Dec
- Typical prime months
- Oct to Mar
- Difficulty
- Beginner
- Filter
- No filter (broadband)
Pick a saved location or share your device location. Your coordinates are used only to calculate tonight and are not stored. To save locations, use the planner.
How to image Salt-and-Pepper Cluster
- At 24 arcminutes, 500 to 800 mm frames it well.
- Short subs are fine, because the cluster is bright.
- Shoot the trio on the same night for a set of images.
Framing: what focal length?
The focal length at which M37 spans about 60% of the long side of the sensor, leaving room around it. Treat it as a starting point; the right framing is a matter of taste.
| Sensor | Focal length |
|---|---|
| 1-inch sensor (13.2 mm) | about 1130 mm |
| APS-C (23.5 mm) | about 2020 mm |
| Full frame (36 mm) | about 3090 mm |
How high does it climb from your latitude?
The highest point M37 reaches in the sky. Above about 60° is excellent, 30° to 60° is workable, and under 30° you are looking through a lot of air.
| Latitude | Highest point | Rating |
|---|---|---|
| 55°N (Scotland, Alaska) | 68° | High in the sky |
| 45°N (Minneapolis, Milan) | 78° | High in the sky |
| 35°N (Los Angeles, Tokyo) | 88° | High in the sky |
| 25°N (Miami, Cairo) | 82° | High in the sky |
| 35°S (Sydney, Santiago) | 22° | Stays low |
Also worth imaging
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