What is Westerlund 2?
Q: What is Westerlund 2?
A: Westerlund 2 is a massive young super star cluster containing some of the hottest, brightest, and most massive stars known.
Q: How old is Westerlund 2?
A: Westerlund 2 is about one or two million years old.
Q: Is Westerlund 2 close to the Earth?
A: No, Westerlund 2 is 20,000 light years away in the Milky Way galaxy.
Q: What are some of the stars found in Westerlund 2?
A: Westerlund 2 contains a dozen of O-type main sequence stars, of which at least three are eclipsing binaries, many very young pre-main sequence stars, and two Wolf–Rayet stars. The core of the cluster contains several examples of rare very hot stars.
Q: Is Westerlund 2 the only cluster discovered by Bengt Westerlund?
A: No, Westerlund 2 was discovered by Bengt Westerlund in the sixties, but its stellar content was assessed only in later years.
Q: Where is the massive eclipsing binary WR20a found in relation to Westerlund 2?
A: The massive eclipsing binary WR20a is found just outside the cluster, at 30 arcseconds (about 1.1 pc in projection), on the lower right side of the cluster center.
Q: What is obscuring Westerlund 2?
A: Westerlund 2 is partly obscured with gas.
