NGC 2105 is a bright open star cluster located in the constellation of Canis Major. It is approximately 4,000 light-years away from Earth and contains several hundred stars, many of which are young and hot. The cluster is estimated to be around 100 million years old. Discovered by John Herschel in 1834, NGC 2105 is notable for its relatively high concentration of stars in a small area. Observations of this cluster can provide valuable insights into stellar formation and evolution, making it an interesting target for both amateur and professional astronomers.