Arp-Madore 1 (also known as AM 1) is a
globular cluster
A globular cluster is a spheroidal conglomeration of stars that is bound together by gravity, with a higher concentration of stars towards its center. It can contain anywhere from tens of thousands to many millions of member stars, all orbiting ...
visible in the constellation
Horologium, located away from Earth. It is one of the most distant known globular clusters of the
Milky Way
The Milky Way or Milky Way Galaxy is the galaxy that includes the Solar System, with the name describing the #Appearance, galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars in other arms of the galax ...
galaxy's
halo
HALO, halo, halos or haloes may refer to:
Most common meanings
* Halo (optical phenomenon)
* Halo (religious iconography), a ring of light around the image of a head
* ''Halo'' (franchise), a sci-fi video game series (2001–2021)
Arts and en ...
; 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
Halton Christian "Chip" Arp (March 21, 1927 – December 28, 2013) was an American astronomer. He is remembered for his 1966 book ''Atlas of Peculiar Galaxies'', which catalogued unusual-looking galaxies and presented their images.
Arp was als ...
and Barry F. Madore, who identified it as a distant globular cluster in 1979, using the
UK Schmidt Telescope
The UK Schmidt Telescope (UKST) is a 1.24 metre Schmidt telescope operated by the Australian Astronomical Observatory (formerly the Anglo-Australian Observatory); it is located adjacent to the 3.9 metre Anglo-Australian Telescope at ...
, after previous researchers at the
European Southern Observatory
The European Organisation for Astronomical Research in the Southern Hemisphere, commonly referred to as the European Southern Observatory (ESO), is an intergovernmental organization, intergovernmental research organisation made up of 16 m ...
had observed its existence but not its classification.
[.]
See also
*
Arp-Madore 2
Arp-Madore 2 (also known as AM 2) is an open cluster of stars in the constellation of Puppis. It is almost 30,000 light-year
A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical dis ...
References
External links
*
{{DEFAULTSORT:Arp-Madore 1
Horologium (constellation)
Globular clusters