M53 (Globular Cluster)
A distant globular cluster in Coma Berenices, about 60,000 light-years away and almost as far from the centre of the galaxy. It is massive and among the most metal-poor globulars.
Globular cluster in Coma Berenices. Magnitude 7.7.
Can you see it from Guyana?
From Georgetown (6.8° N) it climbs to 79° above the northern horizon at its highest; from Lethem (3.4° N), to 75° above the northern horizon. It is highest at midnight on the night of 7 Apr, 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: Not visible to the eye. It lies 7.7° north of Vindemiatrix.
- 10x50 binoculars: A round glow, brighter towards the middle.
- A small telescope (80 to 100 mm): A round, concentrated glow; it needs high power and a dark sky to show any stars.
- A camera: Tiny on camera: it needs 2,000 mm or more of focal length on a tracking mount.
How big, how bright, how far
- Size on the sky: 9′, 29% of the Moon's width (the Moon is about 31′ wide).
- Brightness: magnitude 7.7. Fainter than the faintest stars in Georgetown (4.3) and Lethem (6.0): binoculars or a telescope.
- Distance: 60,300 light-years. The light reaching your eye left it about 60,300 years ago.
- True size: 160 light-years across its catalogued outline; light crosses it in 160 years.
Apparent size from OpenNGC (Mattia Verga), CC-BY-SA-4.0.
What it is made of
- Type
- Globular cluster
- Mass
- About 502,000 times the Sun's mass
- Notable
- Massive and metal-poor: about 502,000 Suns (18th of 167) and [Fe/H] -2.10, poorer than all but 9 of 152.
Measured: Which generation its red giants belong to (1,081 measured near its centre).
- Second generation: 67.2%, born from gas the first stars enriched
- First generation: 32.8%, ± 2.0%
Gas: searches of globular clusters mostly find only upper limits (Pancino et al. 2024, arXiv:2404.05548). Hubble ultraviolet colours split its red giants into a first generation and later, chemically enriched ones: 32.8% ± 2.0% first generation among 1,081 red giants (NGC 5024; Milone et al. 2017, MNRAS 464, 3636, Table 2).
Also in it, not measured:
- Stellar remnants: white dwarfs and neutron stars
- Almost no gas or dust: not in this tally
How we know: Distance from Gaia, Hubble and earlier distances to its stars, combined: Baumgardt & Vasiliev 2021, MNRAS 505, 5957; Baumgardt globular cluster database, combined_table.txt, retrieved 2026-10-21 (NGC 5024: 18.5 +/- 0.18 kpc). True size: the apparent size times the distance (apparent size: OpenNGC (Mattia Verga, CC BY-SA 4.0), commit 4e2398a2). Mass: Baumgardt globular cluster database, combined_table.txt (NGC 5024: 502,000 ± 8,480 Suns), retrieved 2026-10-21; Baumgardt & Vasiliev 2021, MNRAS 505, 5957.
More deep-sky objects: Globular Cluster M3 · Coma Star Cluster (Melotte 111) · Globular Cluster M5 · M68 (Globular Cluster) · Hercules Globular Cluster (M13) · M12 (Globular Cluster)