This ‘jellyfish’ galaxy has bunny ears and swims in a galaxy cluster located in the Coma cluster

Since ancient times has it not been exciting to be an astronomer? 😊

"Astronomers have discovered a “jellyfish” galaxy whose unusual shape and internal mechanisms — including distinctive “bunny ears” and an inner “tail” — are giving researchers an unprecedented view of dynamics within one of the universe’s most extreme environments. ...

a new study ... focused on the internal and external forces influencing a galaxy known as NGC 4858, located in the Coma cluster, more than 300 million light-years from Earth.

Galaxy clusters are some of the largest structures in the universe, containing massive amounts of hot gas, dark matter, and hundreds — even thousands — of galaxies. As an individual galaxy moves through a cluster, extreme outside pressure (called ram pressure or “wind”) strips away a portion of the galaxy’s interior gas. This narrows and elongates the galaxy, giving it a “jellyfish” appearance right down to the long trails of gas and young stars that resemble jellyfish tendrils. ..."

From the abstract:

"We present new CO(2-1) observations (resolution pc) of the Coma cluster jellyfish galaxy NGC 4858 obtained from the ALMA-JELLY large program. Analyzing this data alongside complementary Subaru H and HST (F600LP / F350LP) observations, we find numerous structural and kinematic features indicative of the effects from strong, inclined ram pressure, including an asymmetric inner gas tail. We estimate a highly-inclined disk-wind angle of .

By subtracting a simple circular velocity model, we find 

(1): gas clumps that are being accelerated by ram pressure, and 

(2): signatures of gas clumps that had been previously pushed out of the disk but are now falling inwards.

We also discuss head-tail morphologies in star complexes within the stellar disk that appear to be RPS-influenced.

Lastly, we compare this galaxy to state-of-the-art galaxy ``wind tunnel'' simulations. We find that this galaxy is one of the best nearby examples of strong and inclined ram pressure gas stripping, and of gas that is perturbed by ram pressure but not fully stripped and falls back. We emphasize the importance of torques due to ram pressure in highly-inclined interactions, which help drive gas inwards on the side rotating against the wind, contributing to the formation of asymmetric inner RPS tails."

This ‘jellyfish’ has bunny ears — and swims in a galaxy cluster | Yale News "A Yale-led research team offers a detailed look at the inner workings of a “jellyfish” galaxy hundreds of millions of light-years away."

ALMA-JELLY I: High Resolution CO(2-1) Observations of Ongoing Ram Pressure Stripping in NGC 4858 Reveal Asymmetrical Gas Tail Formation and Fallback (open access)

A Hubble Space Telescope image of NGC 4858, showing the stellar tendrils extending north from the barred spiral disk. The cold molecular gas in NGC 4858, seen by the ALMA radio telescope with its “bunny ear” inner tail, is shown in orange.