AnnSergey E. Koposov, V. Belokurov and G. Torrealba wrote:
(W)e report the discovery of two new star clusters, Gaia 1 and Gaia 2. Gaia 1 is particularly curious, as it is a massive (1.4×104 M), large (∼9 pc) and nearby (4.6 kpc) cluster, situated 10´away from the brightest star on the sky, Sirius!
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Based on the size typical for globular clusters in the MW, we conclude that Gaia 1 is a star cluster, most likely of globular variety given its age and metallicity. It also could be an old open cluster similar to e.g. Berkeley 25 located only ∼1 degree away on the sky from Gaia 1. From the density profile fit we also determine the total number of the satellite’s stars with G<19, N ∼ 1200±120. Assuming the Chabrier IMF and the best-fit isochrone, we deduce the total stellar mass of 14000 M and the V -band luminosity of MV ∼ −4. Note please that these numbers are only the ball-park estimates due to the uncertain age and metallicity of the stellar population.
You can't be Sirius! Globular cluster hidden in glare of brightest star
You can't be Sirius! Globular cluster hidden in glare of brightest star
Globular cluster found in the background of Sirius
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