Stars form from the gravitational collapse of interstellar clouds of gas and dust, and it has long been assumed that this implies that stars in a cluster have about the same age. A recent paper presents new observations of the well-known massive star cluster W3, and concludes that the ages of the stars in the cluster are quite different — from newly born stars to some that are 2 million years old.

This very nice piece of work was carried out by Arjan Bik and coworkers.I have very fond memories of Arjan who was my office mate in Amsterdam where we were both grad students; we had a good time!

You can read more about this in the Press Release; and here’s the ApJ paper.