Fakultät für Physik und Astronomie
STEPHEN PHILLIPS hostreviews.co.uk / UNSPLASH

The Merger History of the Milky Way - What Gaia Revealed

Eva Grebel , ARI

Cosmological models suggest that Milky Way-like galaxies are made up in part of stars that formed in situ and in part of stars that formed in other, smaller galaxies and that were subsequently accreted. Most of the more massive merger events should have occurred more than nine or ten billion years ago. In combination with massive ground-based photometric and spectroscopic surveys, Gaia is confirming and refining the cosmological picture. These data have uncovered numerous stellar tidal streams in our Galaxy, not all of which have known progenitors. Many come from disrupted dwarf galaxies, others from dissolving globular clusters - Gaia permits us to trace the detailed assembly history of our Galaxy, revealing the type of objects, their numbers, their properties, and the time of accretion. The most spectacular discovery is arguably that of the fairly massive dwarf galaxy Gaia-Enceladus or Gaia Sausage, which merged with the Milky Way about 10 Gyr ago. This event contributed many globular clusters and likely triggered the formation of the thick disk. In fact, Gaia data suggest that possibly half of our globular clusters come from merger events. Also, Gaia reveals the orbits of the surviving satellites, providing clues to their origins and future merger history.

ARI Institute Colloquium
11 Nov 2021, 11:15
ARI, Moenchhofstrasse 12-14, Seminarraum 1, 1.OG

Add to calendar Add to calendar
Today:
There are no scheduled talks today.
Upcoming:
How clumpy was the intergalactic medium during reionization?
Frederick Davies
Thu, 4 Apr 2024, 11:00
TBD
TBD
Thu, 4 Apr 2024, 11:00
Recent research results from the HKU Late State stellar evolution team - Strange Galactic alignments and solving the sulphur anomaly in Planetary Nebulae
Quentin Parker
Fri, 5 Apr 2024, 11:00
TBD
TBD
Thu, 11 Apr 2024, 11:00
Explaining the simplicity of the cosmos
Prof. Neil Turok
Thu, 11 Apr 2024, 18:30