Globular Cluster M4
A large, loose globular cluster in Scorpius, located near the bright star Antares. One of the closest globulars, visible in binoculars as a fuzzy patch.
Globular cluster in Scorpius. Magnitude 5.6.
Can you see it from Guyana?
From Georgetown (6.8° N) it climbs to 57° above the southern horizon at its highest; from Lethem (3.4° N), to 60° above the southern horizon. It is highest at midnight on the night of 26 May, in the middle of its season. The page works out tonight's rise, highest point and set for both towns in Guyana time (UTC-4), and where the Moon is.
What you'll see
- Your eyes: Visible to the eye only from a dark site, as a fuzzy star; lost in city skies.
- 10x50 binoculars: A round glow, brighter towards the middle.
- A small telescope (80 to 100 mm): Loose enough that a small telescope resolves many stars, with a bar of stars across the middle.
- A camera: Spans about 40% of an APS-C frame at 1,500 mm (field 0.9° × 0.6°); needs a tracking mount.
How big, how bright, how far
- Size on the sky: 26′, 84% of the Moon's width (the Moon is about 31′ wide).
- Brightness: magnitude 5.6. Fainter than Georgetown's faintest stars (4.3) but brighter than Lethem's (6.0).
- Distance: 7,200 light-years. The light reaching your eye left it about 7,200 years ago.
What it is made of
- Type
- Globular Cluster
- Distance
- Approx. 7,200 Lightyears
- True size
- Approx. 75 Lightyears diameter
- Old Stars (Tens of Thousands): Loosely concentrated, contains white dwarfs and a millisecond pulsar
More deep-sky objects: NGC 6231 (Northern Jewel Box) · Butterfly Cluster (M6) · Ptolemy Cluster (M7) · Eagle Nebula (M16) · Globular Cluster M22 · M25 (Open Cluster IC 4725)