Saturday, January 6, 2018
How to find a star cluster - UNIVERSE
In the latter years of the 18th century, astronomers William and Caroline Herschel began to count stars. William called the technique "star gauging" and his aim was to determine the shape of our Galaxy.
With this simple technique the Herschels produced the first shape estimate for the Galaxy. Fast-forward to the 21st century and now researchers use star counts to search for hidden star clusters and satellite galaxies. They look for regions where the density of stars rises higher than expected. These patches are called stellar over-densities.
It's the perfect meeting of old and new. Astronomers have combined recent data from ESA's Gaia mission with a simple analysis technique from the 18th century to discover a massive star cluster that had previously escaped detection. Subsequent investigations are helping to reveal the star-forming history of our Galaxy, the Milky Way.
Source & further reading:http://sci.esa.int/gaia/59741-how-do-you-find-a-star-cluster-easy-simply-count-the-stars/
Video credit: ESA