Motions of the observed stars in the Milky Way (mpg)

A team of astronomers from Denmark, Switzerland and Sweden [2] has achieved a major breakthrough in our understanding of the Milky Way, the galaxy in which we live.

After more than 1,000 nights of observations spread over 15 years, they have determined the spatial motions of more than 14,000 solar-like stars residing in the neighbourhood of the Sun.

For the first time, the changing dynamics of the Milky Way since its birth can now be studied in detail and with a stellar sample sufficiently large to allow a sound analysis. The astronomers find that our home galaxy has led a much more turbulent and chaotic life than previously assumed.

ESO Press Video eso0411 shows the stars studied during the present programme making their most recent orbital revolution around the Galactic centre before converging into the small volume where they were observed by the team. The duration of the video corresponds to about 250 million years. The yellow dot and white curve show how the Sun moved during this last of its about 20 laps around our Galaxy.