Astronomers knew about the “Local Bubble” — it’s her name— for a long time, just as they had located, in our region of the galaxy, places where stars were emerging. But this is the first time that the two facts have been linked together. In an article published on January 12 in the journal Nature, researchers led by astrophysicist Catherine Zucker, describe the 3D map of these different regions of star formation that they have drawn up.
This map was made possible by data from the European Gaia satellite. In position since 2013 at point L2 – where the James-Webb space telescope is currently going – the mission of the satellite, literally, is to map our galaxy, the Milky Way: eventually, it should have pointed the distance and the movement speed of a good billion stars.
The local Bubble in question is composed mostly of empty space inside: where our solar system and neighboring stars are located. On the other hand, what arouses interest of these astrophysicists is on the surface of the bubble: this “shell” is an aggregate of clouds of gas and dust, representing what remains of stars that have exploded in the past – we are talking about at least 15 dead stars . And in some denser regions of that gas and dust, new stars are forming.
The irregular shape of this bubble could possibly even reveal the locations of stars that exploded millions of years ago: especially as this bubble continues to grow, at an estimated rate of 6 kilometers per second. As for our solar system, it is only a “passing through” visitor: it was not born in this bubble, but entered it perhaps 5 million years ago and will come out of it one day. .