APOD: 2024 September 27 - Stellar Streams in the Local Universe

Good Red Friday morning, Rallypoint, and welcome to the September 27th edition of Astronomy Picture of the Day (APOD). A 'stellar stream' is a collection of stars orbiting a galaxy. Gravity has taken what was once a globular cluster or dwarf galaxy and has torn it apart and stretched out along its new orbit by tidal forces.

The photos shown here are images of galaxies superimposed on their inverse images to better highlight the presence of stellar streams. In each case, what appears to our eyes as a delicate tendril is actually the result of gravity acting on a mass likely hundreds (if not thousands) of times the size of our Sun. And if that isn't enough to boggle the mind, what we see is actually looking back in time. The light from each galaxy has taken thousands of years to reach us. Who knows what those galaxies look like now?