Located 220 million light years from Earth, the spiral galaxy is known as the "jellyfish" galaxy because of the blue ribbons of stars that emerge from it like cosmic tentacles. But when viewed in X-ray light, it reveals an even longer tail of hot gas stretching across 260,000 light years of space. Data from NASA ChandraXRay and the spiral galaxy imaged are shown in purplish blue.
Newly formed stars in the tail are a mystery to astronomers. Galaxies living in a cluster tend to stop forming new stars earlier than galaxies outside the cluster. The "jellyfish" galaxy in the cluster is pulled in by the cluster's gravity, which causes the gas to move like the wind and can lift gas and dust in a process called "ram pressure stripping".
Since galaxies need gas to form stars, this would slow down the star formation process. Astronomers hope to learn how the stripping process changes over time and how this affects the conditions under which new stars form.
A bright blue light surrounded by translucent blue swirls rockets towards the upper left corner of the image, leaving two long ribbons of blue young stars dangling like cosmic tentacles from the galaxy's disc. Against the black background of space filled with twinkling stars, blue gas and star clusters appear to be travelling with the galaxy alongside the streaming tails. In this image, X-ray light is represented by blue in the tail of hot gas flowing behind the galaxy. In visible light, you can see the blue branches like "jellyfish tentacles".
Does it look like a jellyfish to you?