The streak from a Starlink satellite appears in this image of the Andromeda galaxy, taken by the Zwicky Transient Facility, or ZTF, during twilight on May 19, 2021. The image shows only one ...

Dots show locations of stars in the spectroscopic survey superimposed on an image of the Andromeda galaxy (M31). Dots are color coded according to their velocity relative to the Milky Way ...