Trumpler 27 is a possible open cluster in the southern constellation Scorpius. If it exists, it is a few thousand light-years away from the Sun, with estimates ranging from 3,900 light-years (1,210 kiloparsecs)[3] to 6,800 light-years (2,100 kiloparsecs)[4] The name refers to Robert Julius Trumpler's catalog of open clusters, published in 1930.[5]
It was originally thought to be young open cluster in the outer edge of the Sagittarius Arm, still surrounded by interstellar matter.[5] The light from the stars is heavily extinguished and reddened by intervening interstellar dust.[4] The light coming from the stars is also significantly polarized.[6] However, a close study in 2012 could not confirm whether the stars truly form a cluster, or if they are a close alignment of bright stars.[2]
^ abcMoffat, A. F. J.; Fitzgerald, M. P.; Jackson, P. D. (1977). "Trumpler 27: A heavily reddened young open cluster with blue and red supergiants". The Astrophysical Journal. 215: 106. Bibcode:1977ApJ...215..106M. doi:10.1086/155338.
^ abThe, P. S.; Stokes, N. (1970). "A study of the southern open clusters : TR 27, TR 28, NGC 6416, NGC 6425". Astronomy and Astrophysics. 5: 298. Bibcode:1970A&A.....5..298T.
^Bakker, R.; The, P. S. (1983). "An investigation of the heavily reddened young open cluster TR 27 on the Walraven photometric system". Astronomy and Astrophysics Supplement Series. 52: 27. Bibcode:1983A&AS...52...27B.