Our Sun is within 300 parsecs (about 1,000 light-years) of a 2,700-parsec (about 9,000 light-years) long sinusoidal dense gas cloud known as the Radcliffe wave. The wavy shape of this structure was discovered using 3D dust mapping, but initial kinematic investigations of its oscillatory motion were inconclusive. Radcliffe waves oscillate in the plane of the Milky Way galaxy, radiating away from the galaxy's center, according to a new study.
Radcliffe waves next to the sun (yellow dot) in a cartoon model of the Milky Way. The blue dots are a group of baby stars.The white line is the theoretical model by Konietzka other. It describes the current shape and movement of the wave. The magenta and green lines show how the waves will move in the future. Image credit: Ralf Konietzka / Alyssa Goodman / Worldwide Telescope.
“By using the movement of baby stars born in gas clouds along Radcliffe waves, we can track the movement of the natal gas and show that the Radcliffe waves are actually rippling,” says Ralph.・Dr. Konietzka said. He is a student at Harvard University and the Smithsonian Center for Astrophysics.
In 2018, astronomers mapped the 3D location of a stellar nursery in the sun's galactic neighborhood.
By combining new data, ESA's Gaia Mission Using a data-intensive “3D dust mapping” technique, they noticed an emerging pattern, leading to the discovery of the 2020 Radcliffe wave.
“This is the largest coherent structure that we know of, and it's in our immediate vicinity,” said Dr. Katherine Zucker, an astronomer at the Harvard University & Smithsonian Center for Astrophysics.
“It's been there all along. We just didn't know it because we weren't able to build high-resolution models in 3D to show the distribution of gas clouds near the Sun.”
Although the 3D dust map clearly showed that Radcliffe waves were present, sufficient measurements were not available at the time to confirm whether the waves were moving.
But in 2022, astronomers used a new release of Gaia data to assign 3D motion to young star clusters in Radcliffe waves.
By understanding the location and movement of the clusters, they were able to confirm that the entire Radcliffe wave was indeed undulating, moving like what physicists call a “traveling wave.”
“Traveling waves are the same phenomenon you see in sports stadiums, where people take turns standing and sitting to do waves,” Konietzka said.
“Similarly, star clusters along Radcliffe waves move up and down, creating patterns that travel through the galaxy's backyard.”
“In the same way that fans in a stadium are pulled back into their seats by Earth's gravity, Radcliffe waves are oscillated by the Milky Way's gravity.”
No one yet knows what causes Radcliffe waves or why they behave the way they do.
“Now we can test all the different theories about why the waves formed in the first place,” Dr. Zucker said.
“Those theories range from the explosion of a giant star called a supernova to disturbances outside the galaxy, such as a dwarf satellite galaxy colliding with the Milky Way,” Konietzka added.
“It turns out we don't need significant dark matter to explain the motion we observe.”
“The gravity of ordinary matter is enough to move waves.”
Furthermore, the discovery of this oscillation has raised new questions about the predominance of these waves in both the Milky Way and other galaxies.
Radcliffe waves appear to form the backbone of the Milky Way's closest spiral arms, so the ripples in these waves may be due to the oscillations of galactic spiral arms in general, making galaxies even more dynamic than previously thought. It may suggest that you are doing something.
“The question is: What causes the displacement that causes the ripples that we see?” said Professor Alyssa Goodman, an astronomer at Harvard University and the Smithsonian Center for Astrophysics.
“And does it happen throughout the galaxy? In every galaxy? Does it happen sometimes? Does it happen all the time?
of result appear in the diary Nature.
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R. Konietzka other. Radcliffe waves are oscillating. Nature, published online on February 20, 2024. doi: 10.1038/s41586-024-07127-3
Source: www.sci.news
