FGC 1287 is part of a triplet of galaxies in the outskirts of the galaxy cluster Abell 1367, or Leo Cluster, some 300 million light-years away. In the left part of the image, the white contour lines represent regions of neutral hydrogen (gas made of atoms with one proton and one electron).

Spiral galaxies are normally embedded in extensive envelopes of neutral hydrogen, like the one at the bottom left of the image.

What is unusual is the very long tail of neutral hydrogen off the spiral galaxy FGC 1287, well beyond its visible part.

Astronomers are still determining what mechanism is stripping the gas from this galaxy.

Galaxy chosen by Tom Scott.