This NASA/ESA photograph of the Hubble Space Telescope shows the serenely drifting jellyfish galaxy JW39. This galaxy, one of many jellyfish galaxies Hubble has observed over the past two years, lies around 900 million light-years away in the constellation Coma Berenices.

Hubble Photographs a Moving Galaxy!

What are the effects of galaxy clusters on the shape and gas content of galaxies?

Although it seems serene, this jellyfish galaxy is actually drifting in a galaxy cluster, which is an extremely dangerous environment. The gravitational attraction of larger companions frequently warps galaxies in galaxy clusters, twisting them into a variety of designs. Additionally, a searingly hot plasma known as the intracluster medium dominates the area between galaxies in a cluster. Despite the extreme thinness of this plasma, galaxies moving through it have an almost current-like sensation, and this interaction can deplete galaxies of star-forming gas.

What Phenomenon Creates the Distinctive Trailing Tentacles in Jellyfish Galaxies?

Ram-pressure stripping, or the interaction between the intracluster medium and the galaxies, is what causes the jellyfish galaxy’s trailing tentacles. As JW39 traveled through the cluster, the intracluster medium’s pressure sucked away gas and dust, creating long trailing ribbons of star formation that now extend away from the galaxy’s disk.

What is the impact of harsh environments on star formation in jellyfish galaxies?

Astronomers used Hubble’s Wide Field Camera 3 to investigate these trailing tendrils in great detail because they represent a particularly hostile environment for star formation. Surprisingly, researchers found little difference between star production in the galaxy disk and star formation in the ‘tentacles’ of jellyfish galaxies.

This view from the NASA/ESA Hubble Space Telescope shows the globular cluster NGC 6325, which is closely packed.  Glistening Star Cluster is located in the constellation Ophiuchus, approximately 26,000 light-years from Earth.


How do astronomers use globular clusters to study the birth of stars?

Globular clusters, such as NGC 6325, are tightly bonded groups of stars with tens of thousands to millions of members. They can be found in all kinds of galaxies and serve as real-world research facilities for astronomers who investigate the birth of stars. Because the constituent stars of globular clusters tend to develop at around the same time and with comparable starting compositions, astronomers may use them to fine-tune their theories of how stars grow.

Why did astronomers focus on

Glistening Star Cluster

 examining this particular cluster?

Astronomers examined this particular cluster

 in order to find a hidden monster rather than to understand star formation better. Though it appears to be serene, astronomers believe this cluster contains an intermediate-mass black hole that subtly alters nearby stars’ velocity. Previous research discovered that the dispersion of stars in some highly concentrated globular clusters – those with stars packed relatively tightly together – differed slightly from what astronomers predicted.

How did researchers investigate the possibility of a black hole in NGC 6325?

This discrepancy shows that a black hole may be hiding at the center of at least part of these tightly packed globular clusters, maybe NGC 6325. To investigate this concept further, researchers used Hubble’s Wide Field Camera 3 to observe a broader sample of densely packed globular clusters, including this star-studded image of NGC 6325. This image also includes data from Hubble’s Advanced Camera for Surveys.