Beautiful Chaos

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[/caption] Can you imagine living in this region of space? Just think of the beautiful views you'd have in the sky – that is, if you survived the chaos as one galaxy is passing through the core of three other galaxies at ridiculous (ludicrous?) speeds (3.2 million km per hour / 2 million miles per hour) generating a shock wave of gas and X-rays.

This is Stephen's Quintet, A compact group of galaxies, discovered about 130 years ago, located about 280 million light years from Earth. The curved, light blue ridge running down the center of the image shows X-ray data from the Chandra X-ray Observatory. The galaxy in the middle, NGC 7318b is passing through the core of the other galaxies at high speed and is thought to be causing the ridge of X-ray emission by generating a shock wave that heats the gas. The most prominent galaxy in front (NGC 7320) is actually far away from the other galaxies and is not part of the group.

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See the Chandra webpage for a roll-over labeled version

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Additional heating by supernova explosions and stellar winds has also probably taken place in Stephan's Quintet. A larger halo of X-ray emission - not shown here - detected by ESA's XMM-Newton could be evidence of shock-heating by previous collisions between galaxies in this group. Some of the X-ray emission is likely also caused by binary systems containing massive stars that are losing material to neutron stars or black holes.

Stephan's Quintet provides a rare opportunity to observe a galaxy group in the process of evolving from an X-ray faint system dominated by spiral galaxies to a more developed system dominated by elliptical galaxies and bright X-ray emission. Being able to witness the dramatic effect of collisions in causing this evolution is important for increasing our understanding of the origins of the hot, X-ray bright halos of gas in groups of galaxies.

Source:

Chandra

Nancy Atkinson

Nancy Atkinson

Nancy Atkinson is a space journalist and author with a passion for telling the stories of people involved in space exploration and astronomy. She is currently retired from daily writing, but worked at Universe Today for 20 years as a writer and editor. She also contributed articles to The Planetary Society, Ad Astra (National Space Society), New Scientist and many other online outlets.

Her 2019 book, "Eight Years to the Moon: The History of the Apollo Missions,” shares the untold stories of engineers and scientists who worked behind the scenes to make the Apollo program so successful, despite the daunting odds against it. Her first book “Incredible Stories From Space: A Behind-the-Scenes Look at the Missions Changing Our View of the Cosmos” (2016) tells the stories of 37 scientists and engineers that work on several current NASA robotic missions to explore the solar system and beyond.

Nancy is also a NASA/JPL Solar System Ambassador, and through this program, she has the opportunity to share her passion of space and astronomy with children and adults through presentations and programs. Nancy's personal website is nancyatkinson.com