| Arp-Madore 1 | |
| Epoch: | J2000.0 |
| Constellation: | Horologium |
| Ra: | [1] |
| Dist Ly: | 398,000 |
| Dist Pc: | 122,000 |
| Appmag V: | 15.07 |
| Size V: | 1.288 by 0.691 |
| Names: | 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 123.3kpc away from Earth.[2] It is one of the most distant known globular clusters of the Milky Way galaxy's halo;[3] [4] its distance gives it interest as a test case for gravitational theories.[5] AM 1 has a visual magnitude of 15.07.[6]
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,[7] after previous researchers at the European Southern Observatory had observed its existence but not its classification.[8]