Messier 46 is an open star cluster located in the constellation Puppis. It is approximately 5,400 light-years away from Earth and contains around 100 stars, with its brightest members being of spectral type B. The cluster is estimated to be about 300 million years old. One interesting feature of Messier 46 is the presence of a planetary nebula, known as NGC 2438, which appears to be superimposed on the cluster. This nebula is actually much closer to Earth than the cluster itself, highlighting the depth of space and the varying distances of celestial objects.