How massive is the Milky Way? According to a new study using data from ESA's Gaia spacecraft, less than we thought. A new estimate puts the Milky Way's mass at 200 billion times the mass of the Sun, which is 4-5 times less than previous estimates that pegged it closer to a trillion solar masses. Using detailed information about millions of stars, astronomers were able to build an extremely accurate rotation curve for the Milky Way and use that to estimate its mass. They found that the rotation of the Milky Way isn't typical for large spiral galaxies, decreasing its estimated mass.

What is the mass of the Milky Way galaxy? It is difficult to measure the mass of a galaxy, and previous estimates appear to have been inaccurate. There is a new study that has used data from the Gaia spacecraft to calculate a more accurate mass for the Milky Way. The study found that the Milky Way is much less massive than previously thought, with a mass of about 200 billion solar masses. This means that the Milky Way has less dark matter than previously thought.