We’ve never seen our galaxy in such detail before. Since last May, the planets, stars, quasars
and other celestial objects in the Milky Way may be located in the most detailed and accurate map of our galaxy to date. The European satellite Gaia is equipped with a camera that can photograph a 1-euro coin on the surface of Earth from the Moon. Now, professional and amateur astronomers, as well as the public, have free and unlimited access to this map.
The map has several layers representing parameters such as brightness, density, and size of stars, their speed, and the distance between them. For example, temperature is represented by colours ranging from red (warmer temperatures) to blue (cooler temperatures). The result is a mixture of colours and shapes that team-member Antonella Valenari defines as “a beautiful work of art offering a lot of information”.
Thanks to this map, scientists will be able to know in detail this corner of our universe and get a sense of its mysterious, yet-unknown origin. There’s more: by analysing how stars move, they will find out how dark matter (a type of matter that accounts for about 80% of the matter-energy in the universe, does not interact with electromagnetic radiation, and is invisible throughout the electromagnetic spectrum) is distributed in our galaxy.
This is the second map designed after images from the Gaia satellite, which has collected data for 22 months. The first map was published in 2016 and contained the movement and distance of “only” two million stars, a task that took just over a year to complete. Gaia will be orbiting the Earth and photographing space until 2020, at least.