Laevens 1 is a faint
globular cluster in the constellation
Crater
Crater may refer to:
Landforms
*Impact crater, a depression caused by two celestial bodies impacting each other, such as a meteorite hitting a planet
*Explosion crater, a hole formed in the ground produced by an explosion near or below the surfac ...
that was discovered in 2014. It is also known as Crater, the Crater cluster and PSO J174.0675-10.8774.
At a distance of it is the most distant Milky Way globular cluster yet known, located in the
galactic halo surrounding the
Milky Way
The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye ...
galaxy.
With an age of only 7.5 Gyr, it is likely to have been incorporated into our galaxy long after the formation of the Milky Way, probably during an interaction with the
Small Magellanic Cloud
The Small Magellanic Cloud (SMC), or Nubecula Minor, is a dwarf galaxy near the Milky Way. Classified as a dwarf irregular galaxy, the SMC has a D25 isophotal diameter of about , and contains several hundred million stars. It has a total mass of ...
.
Some analyses initially categorized it as a satellite galaxy, because of the presence of a handful of
blue loop
In the field of stellar evolution, a blue loop is a stage in the life of an evolved star where it changes from a cool star to a hotter one before cooling again. The name derives from the shape of the evolutionary track on a Hertzsprung–Russell ...
stars and a sparsely populated
red clump; the existence of some of these types of stars in Laevens 1 would imply relatively recent star formation (within 400 Myr). Such recent formation would be very atypical for a globular cluster;
more recent work suggests that some of these stars were erroneously assigned membership of the cluster, distorting the overall result. After removing these, the subsequent reanalysis concluded that Laevens 1 is a faint, intermediate-age globular cluster.
Laevens 1 is orbiting the galaxy at approximately the same distance as the ultrafaint dwarf galaxies
Leo IV and
Leo V. This hints that all three satellites may once have been closely associated before falling together into the Milky Way halo.
See also
*
Globular cluster
*
Dwarf spheroidal galaxy
References
External links
* {{cite simbad, title=NAME Laevens 1
Globular clusters
Crater (constellation)