Surroundings Andromeda Galaxies, three dozen small galaxies, are not acting as scientists expected.
NASAThe Hubble Space Telescope trained Andromeda to dig deeper into how orbital satellite galaxies formed and changed over time. What they found revealed a group of dwarf galaxies that were completely different from the ones that were circling milky way.
Approximately 2.5 million Light year Away, the neighbours of these spaces formed most of the stars long ago. However, as computer simulations suggest, rather than stopping production, they slowly continued to create new stars from gas stockpilings.
“The star formation really continued later, but this is not what you would expect from these dwarf galaxies,” said Alessandro Savino, an astronomer from Berkeley, California. statement. “No one knows what to make of that.”
Small galaxies have stopped making stars for billions of years. After that, I rebooted.
Hubble captured the view of birds of known dwarf galaxies orbiting the large Andromeda galaxy. These 36 small satellites are circled in yellow.
Credit: NASA/ESA/ALESSANDRO SAVINO/JOSEPH DEPASQUALE/AKIRA FUJII DSS2
In the past, scientists have mainly observed d-star galaxies near the Milky Way, but they never knew if they were representatives of others in the universe. That’s why they pointed to Hubble orbiting the Earth. The nearest big galaxythere are a herd of satellite galaxies.
studyIt is published in Astrophysical Journalbased on observations from over 1,000 telescope orbits. The Cleaning Science Campaign allowed astronomers to build detailed 3D maps of Andromeda’s 36 dwarf galaxies, reconstructing how they created new stars over 13.8 billion years. big bang. The image offers a Seey view of Andromeda and its environment.
Masculine light speed
In addition to the years that featured long-standing stars in the dwarf galaxy, scientists were surprised that half were sitting on the same plane moving in the same direction. but, Merger and conflict Typically, objects move in an inconsistent direction.
“That’s weird,” said Daniel Wise, a lead investigator in Berkeley, California, in a statement. “In fact, finding satellites in that configuration was a complete surprise, but I don’t fully understand why they look like that.”
Astronomers have learned that galaxies tend to start small and grow by collecting gas It fuses with other galaxies. However, the galaxy of most d stars that created the stars before The era of reionization I have never returned to business since then. Reionization was a major transition era that occurred more than 13 billion years ago. That was when the baby’s universe was converted from a neutral state to something filled with free electrons and protons.
The animation above provides a fly-around view of the Andromeda galaxy and its surrounding dwarf galaxy, based on Hubble data.
As most small galaxies have turned off star-building activities in the first hundreds of millions of years of the universe, many scientists believe that it is due to reionization. However, some researchers do I question that idea.
Astronomers suspect that Andromeda had a major collision with another galaxy relatively recently, perhaps 2-5 billion years ago. Meanwhile, the Milky Way probably hadn’t gotten used to another galaxy for 800-10 billion years. Andromeda Clash – and its larger scale – It explains Galaxy’s exotic and diverse satellite systems.
The study only deepened the team’s speculation that dwarf galaxies are nothing like home-like. They can have a wide range of destinies, and researchers need more observations to imagine assumptions and confirm why.
“Everything scattered across the Andromeda system is very asymmetric and perturbed. It seems that something important happened too long ago,” Wise said. “Our work shows that low-mass galaxies in other ecosystems are following evolutionary paths that we know from satellite galaxies in the Milky Way.”
