The History of the Milky Way Comes Into Focus

Christopher Intagliata said that when you look up at the stars, you are looking at Rome. The Eternal City has layers upon layers of history. The astronomer Hans-Walter Rix said so.

There were glory days, there were disasters, and all of these things happen in the life of the universe. You can see individual episodes in actual detail if you look at the stars in the Milky Way.

Rix and a colleague at the Max-Planck Institute for Astronomy in Germany have gone star by star to determine the ages of nearly a quarter million stars. They have been able to reconstruct some of the major life events in the universe over the last 13 billion years.

It showed that the youth and childhood of the Milky Way was turbulent, but we have lived a sheltered life compared to most other galaxies. The suburbs grew peacefully and sprawled as gas poured in.

The thick disk of the galaxy began to form 800 million years after the Big bang, according to the astronomer. Around 11 billion years ago, a satellite crashed into the Milky Way.

There was a burst of star formation or an increase of star formation in our own Milky Way. That suggests that the perturbance that this in-falling satellite created, caused a lot of gas in our Milky Way to form stars.

The details are in the journal Nature. A time-resolved picture of our Milky Way's early formation history.

People have done simulations of the formation of the Milky Way before.

Rix: I think what our work has done is it shows a long-suspected picture is coming into focus.

This work lays out a more definitive playbill of the acts in this drama.

The above text is a transcript.