[The Epoch Times, 18 Samhain, 2024](Epoch Times reporter Chen Juncun reported) The National Aeronautics and Space Administration’s (NASA) Hubble Space Telescope picked up two connected spiral galaxies. The pair of galaxies, 390 million light years away from Earth, are interacting and may eventually become elliptical galaxies.
NASA released this image taken by the Hubble Space Telescope on November 15. The two spiral galaxies pictured together are called MCG+05-31-045.
There are over a thousand known galaxies in the Coma Cluster. Amateur astronomers can easily see several of them in their backyard with a simple telescope.
Most of the galaxies in the Coma Cluster are elliptical galaxies, similar to dense galaxy clusters like the Coma Cluster. Many elliptical galaxies are formed by close encounters between galaxies, and these collisions can build them up or even tear them apart.
Although stars in interacting galaxies can stay together, their gas is twisted and compressed by gravity, and is quickly used to form new stars. When hot blue giant stars die, there is not much gas left to replace them with a new generation of young stars.
When spiral galaxies interact with each other, gravity disrupts the regular orbits in which the spiral arms are formed. Whether through a merger or a close pass, the result is a nearly gasless elliptical galaxy in which aging stars orbit in asymmetric circular orbits. (Further reading:The Webb Telescope captured 19 spiral galaxies showing stellar evolution)
MCG+05-31-045 is likely to suffer a similar fate. When smaller spiral galaxies are torn apart and merged into larger galaxies, many new stars form, and the hot blue stars burn out quickly, leaving cooler, redder stars in the galaxy. elliptical belt similar to other elliptical galaxies in the Coma Cluster. But this process takes millions of years to complete.
Also on November 8, NASA released images of the galaxy NGC 1672 taken by the Hubble Space Telescope. This barred spiral galaxy is so bright it looks like a light show.
Spiral galaxy NGC 1672 photographed by the Hubble Space Telescope. (NASA)
NASA pointed out that NGC 1672 is located in the constellation Dorado, 49 million light-years away from Earth. It displays an impressive array of celestial lights.
Like any spiral galaxy, the disk of NGC 1672 is filled with bright stars that give the galaxy a beautiful glow. Along its two giant spiral arms, bubbles of hydrogen gas emit a stunning red light, produced by radiation from the newborn stars that host them.
Some very special stars are embedded in a ring of hot gas near the center of the galaxy. These new hot stars emit powerful X-rays. The brightest X-ray source is closer to the center of the galaxy, the active galactic nucleus.
This active galactic nucleus led to the galaxy being identified as a Seyfert galaxy. This type of galaxy is very active and makes up about 10% of the galaxies in the universe. They are usually spiral galaxies and have very bright cores, due to large amounts of radiation released from material accreting to the supermassive black hole at their centre.
In addition to the bright young stars and X-ray cores, another highlight of this image is called SN 2017GAX.
Caused by a cardiac collapse and subsequent massive star explosion, SN 2017GAX went from invisible to a new point of light in the sky in a matter of days. In the image above, the supernova has faded, creating a small green dot in the curve of the right spiral arm.
Astronomers wanted to look for any possible companion stars to the progenitor supernova, so they took images of the decaying supernova. ◇
Editor-in-Chief: Ye Ziwei #
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Q: What role does the Hubble Space Telescope play in observing and understanding interacting galaxies like MCG+05-31-045 and NGC 1672?
Interview with Dr. Sarah Thompson and Dr. Michael Kavic, experts in astrophysics and observational astronomy, about the Hubble Space Telescope’s recent observations of interacting galaxies MCG+05-31-045 and NGC 1672.
Thematic Section 1: Introduction to MCG+05-31-045 and NGC 1672
Q: Can you tell us more about the two interacting spiral galaxies, MCG+05-31-045, and NGC 1672? What sets them apart from other galaxies in the Coma Cluster?
A: Dr. Sarah Thompson: Sure! MCG+05-31-045 is a pair of interacting spiral galaxies located about 390 million light-years away from Earth. What’s interesting about them is that they’re part of the Coma Cluster, which is known for having a large number of elliptical galaxies. Elliptical galaxies are formed when spiral galaxies interact and merge, leading to the formation of older stars.
Dr. Michael Kavic: NGC 1672 is another barred spiral galaxy located about 49 million light-years away. It’s unique because it has a ring of hot gas around its central region, emitting X-rays from the energy released by newborn stars. Additionally, it has a bright core, indicating the presence of an active galactic nucleus — a region with a high concentration of mass, most likely a supermassive black hole.
Thematic Section 2: Spiral Galaxies and Their Evolution
Q: How do spiral galaxies like MCG+05-31-045 and NGC 1672 form? What triggers their evolution into elliptical galaxies?
A: Dr. Sarah Thompson: Spiral galaxies like MCG+05-31-045 form from the gravitational pull of gas and dust clumping together in a disk shape, with two spiral arms formed by density waves. As these galaxies interact with each other, their gas and dust are compressed, triggering a burst of star formation. Eventually, this gas is depleted, leaving behind old, redder stars in an elliptical configuration —
