Red supergiants “dance” because they have too much gas
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Scientists can finally explain why some giant stars appear to fly in the sky when they aren’t actually moving. study.
Dancing stars, known as red supergiants, are giant stellar objects that swell and cool as they approach the end of life. These stars Sun It can have a diameter of up to 700 times the diameter of the sun.This corresponds to the surface of the Sun reaching beyond the orbit of Mars (engagement). Mercury, Venus, Earth And in the process, the red planet). However, despite their huge height, these slowly dying giant animals can be very difficult to find exactly.
Astronomers can usually locate a star almost exactly by identifying the point of the center of light that the star emits, usually at the center of the star’s light, or usually at the center of gravity or the center of gravity. For most stars, the center of the photo occupies a fixed position. However, on red supergiants, this point wobbles across the star and appears to move slightly from side to side over time. Its movement provides the exact cosmic address of the star, making it difficult to identify the center of gravity of the star, which does not move around like the center of a swaying photo.
In a new study, researchers compared dancing red supergiants to smaller main sequence stars, or stars in the stable part of their lives. Scientists have examined the stars in the cluster of Perseus. This is an area where stars such as red supergiants are concentrated, about 7,500 light-years away from the stars. Solar system — Uses data from the Gaia Space Observatory of the European Space Agency.
Related: The newly discovered “Micro Nova” jumps out of the magnetic poles of a cannibalistic star.
“We found that the position uncertainty of red supergiants is much greater than that of other stars,” said a research co-author, an astronomer at the University of Hawaii and director of the Institute for Space Particle Biophysics in Munich, Germany. Rolf Kudritsuki of. Said in a statement (Opens in a new tab)..
To determine why these stars wobble, the team created a surface intensity map of the red supergiant, calculated radiation measurements, and used hydrodynamic simulations to show changes in the star’s 3D skin. ..
Maps reveal that the surface of red supergiants is highly dynamic, has a massive gaseous structure that increases and decreases over time, and emits bursts of energy stronger than other surface regions. These temporary, yet high-intensity structures flare brighter than the rest of the star’s surface, shifting the center of light. When the bright structure flares up on the left side of the red supergiant, the center of the photo also moves to the left side.
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The huge size of the red supergiant can explain why this is happening. The outer shell of most stars is made up of thousands of adjacent convection cells. An elongated pocket of rotating gas, primarily hydrogen and helium, circulates hotter gas from the inside to the outside of the star, where it cools and sinks like bubbles. Inside the lava lamp.
However, the red supergiant is so huge that gravity On their surface, they are much weaker than their core. Therefore, their convection cells are much larger than other stars, occupying 20% to 30% of the effective radius of red supergiants, or 40% to 60% of their diameter. Studies show that larger convection cells can transport more gas to the surface of the star, creating a very bright structure that causes the movement of their light centers.
Team data show that the sizes of these surface structures can vary. “The largest structures evolve over a time scale of months or years, while the smaller structures evolve over a period of weeks,” said the lead research author, astronomer at the Lagrange Institute in Nice, France. Andrea Chiavassa and Maxplank Institute for Astrophysics (MPIA) Munich, said in a statement. This means that the position of the center of the star’s photo is always fluid, he added.
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Astronomers suspect that red supergiants may play an important role in the evolution of the galaxy. Giant stars exhale large amounts of gas and heavy elements that are important for the birth of new stars. Exoplanet.. The bright and enormous surface structure of supergiants may help release these important substances, and future studies of star wobble will help solve exactly how it happens. There is a possibility.
“The pattern of red supergiant dance in the sky will tell us more about their boiling envelope,” research co-author and MPIA director Selma de Mink said in a statement. I did. “We can extract important information about stellar dynamics and better understand the physical processes that cause intense convection in these stars.”
This study was published in the journal on May 6th. Astronomy and astrophysics (Opens in a new tab)..
Originally published on Live Science.
Red supergiants “dance” because they have too much gas
Source link Red supergiants “dance” because they have too much gas
