Arp-Madore 1
| Arp-Madore 1 | |
|---|---|
Globular cluster Arp-Madore 1 | |
| Observation data (J2000.0 epoch) | |
| Constellation | Horologium |
| Right ascension | 03h 55m 02.70s |
| Declination | −49° 36′ 52.0″ |
| Distance | 398,000 (122,000) |
| Apparent magnitude (V) | 15.07 |
| Apparent dimensions (V) | 1.288 by 0.691 ′ |
| Physical characteristics | |
| Other designations | E1, AM 0353-094, C 0353-497, C 0354-498, AM 1, ESO 201-10, LEDA 14098, SGC 035336-4945.6 |
Arp-Madore 1 (also known as AM 1) is a globular cluster visible in the constellation Horologium, located 123.3 kiloparsecs (402,000 light-years) away from Earth. It is one of the most distant known globular clusters of the Milky Way galaxy's halo; its distance gives it interest as a test case for gravitational theories. AM 1 has a visual magnitude of 15.07.
It is named after Halton Arp and Barry F. Madore, who identified it as a distant globular cluster in 1979, using the UK Schmidt Telescope, after previous researchers at the European Southern Observatory had observed its existence but not its classification.