NGC 2540 is a bright open star cluster located in the constellation of Monoceros. It is approximately 1,500 light-years away from Earth and contains several young, hot stars that are primarily blue in color. The cluster is estimated to be around 100 million years old. Discovered by John Herschel in 1834, NGC 2540 is notable for its relatively high concentration of stars within a small area. Observations of this cluster can provide insights into stellar evolution and the dynamics of star formation in open clusters.