Gaia-Enceladus tagged posts

Scientists have succeeded in dating some of the oldest stars in the galaxy with unprecedented precision by combining data from the stars’ oscillations with information about their chemical composition.

The team, led by researchers at the University of Birmingham, surveyed around 100 red giant stars, and were able to determine that some of these were originally part of a satellite galaxy called Gaia-Enceladus, which collided with the Milky Way early in its history.

The results, published in Nature Astronomy, revealed that the group of stars surveyed all have similar ages, or are slightly younger than the majority of the stars known to have started their lives within the Milky Way...

N-body simulation of the merger of a Milky Way-like galaxy (with its stars in blue) and a smaller disky galaxy resembling the Small Magellanic Cloud in mass (with it stars in red). At the beginning, the two galaxies are clearly separated, but gravity pulls them together and this leads to the full accretion of the smaller one. Distinguishing the accreted stars from the rest is not easy by the final stage, but it is possible using the motions of the stars and their chemical composition. Credit
Credit: H.H. Koppelman, A. Villalobos, A. Helmi (University of Groningen)

Some ten billion years ago, the Milky Way merged with a large galaxy. The stars from this partner, named Gaia-Enceladus, make up most of the Milky Way’s halo and also shaped its thick disk, giving it its inflated form...