Carina OB2 explained

Carina OB2 is a giant OB association in the constellation Carina. It contains anywhere from 91 to 157 stars, many of which are hot blue stars of spectral types B and O. It is located 3.1 kiloparsecs distant and is around 4 million years old.^[1]

Notes and References

1. Garcia. Beatriz. 1994. A study of Carina OB2 association. 2: Analysis and discussion of the data. Astrophysical Journal, Part 1. 436. 2. 705–19. 10.1086/174944 . 1994ApJ...436..705G. free.