Orbits of the nearby stars around the galaxy

The movement of almost 75 thousand stars from the Gaia Catalogue of Nearby Stars in their orbits around the centre of the galaxy are shown in this video. Their motion for the next 500 million years is shown from three different perspectives (face-on, side view, and perspective). Each second on the video corresponds to six million years, and the field of view for each image of the galaxy is 100 000 light years wide.

Stars in the Gaia Catalogue of Nearby Stars (GCNS) come from Gaia’s Early Data Release 3 (Gaia EDR3), which was made public on 3 December 2020. The GCNS contains 74 281 stars within 100 pc (326 light years) of the Sun that have measured radial velocities in EDR3. The orbits have been computed to take into account the gravitational field of the Milky Way, but not the gravitational interaction between the stars.

Most of the stars in the GCNS have a disc-like orbit, similar to the Sun, with small deviations away from circularity. They stay close to the Galactic plane but form long ribbons that eventually wind themselves around the galaxy.

The solar neighbourhood is also visited by stars from the outer reaches of the galaxy. This part is known as the halo, and stars from here are shown in orange. Their orbits have larger deviations from circles, and can be seen heading into the outer parts of the galaxy, away from the Galactic plane. Stars coming from or going to the inner parts of the galaxy are also shown (yellow dots).

The Hyades and Coma Berenice star clusters are also clearly visible as small clumps of stars (blue dots).

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