Astronomers Uncover the Astonishing Longest Gas Tail: Scientists have confirmed the longest-known tail of gas extending behind a group of galaxies (groups of approximately 50 or fewer galaxies bonded together by gravity). The galaxy group, designated NGC 4839, is located near the border of the Coma galaxy cluster, one of the largest known clusters about 340 million light-years away.
As the galaxy group approaches the centre of the Coma cluster, its hot gas is stripped away by its collision with cluster gas, leaving behind an X-ray emitting trail. According to new data from NASA’s Chandra Observatory, the tail is 1.5 million light-years long. It is tens of millions of times longer than the distance between the Sun and the nearest star, making it the longest tail ever observed lingering behind a cluster of galaxies.
The results will aid astronomers in gaining a better understanding of how galaxy clusters expand to such enormous sizes.
Astronomers Uncover the Astonishing Longest Gas Tail
According to the researchers, the gas in the tail behind NGC 4839 will eventually combine with the vast quantity of heated gas already present in the Coma Cluster.
Using Chandra data to analyse the atmosphere in front of the cluster of galaxies, the scientists made a further intriguing discovery. They detected a shock wave similar to a supersonic jet’s sonic explosion, indicating that NGC 4839 is hurtling through the galaxy cluster at an astounding speed of approximately 3 million miles per hour.
In addition, the team examined the turbulence within the tail’s gas and discovered that NGC 4839’s gas exhibits a low level of turbulence, indicating that heat conduction within the galaxy cluster is low.
On one side of the gas tail, the scientists also discovered potential evidence of a structure known as Kelvin-Helmholtz instabilities. Caused by differences in the velocity of adjacent strata of moving gas or fluid, these structures are frequently observed in various space and terrestrial environments, such as cloud formations. According to the researchers, the presence of this structure within NGC 4839 indicates that the gas within the tail has either a feeble magnetic field or a low viscosity.