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Scientists were able to observe, for the first time, the destruction of a young planet or planets around a nearby star. Observations from NASA's Chandra X-ray observatory indicate that the parent star is devouring planetary debris. This discovery provides insight into the processes that affect the survival of infantile planets.
Since 1937, astronomers have questioned the curious variability of a young star named RW Aur A, located about 450 light-years from Earth. Every few dozen years, the optical light of the star faded briefly before becoming luminous again. In recent years, astronomers have observed the gradation of stars more frequently and for longer periods.
The illustration of this artist depicts the destruction of a young planet or planets, which scientists have seen for the first time Observatory of the Rays. Credits: Illustration: NASA / CXC / M. Weiss; X-ray Spectrum: NASA / CXC / MIT / HMGünther
Using Chandra, a team of scientists was able to discover what caused the most recent star-grading event: a collision of two infantile planetary bodies , including at least one object large enough to be a planet. As the resultant planetary debris fell into the star, it would produce a thick veil of dust and gas, temporarily obscuring the light of the star.
"Computer simulations have long predicted that planets may fall into a young star, but never before," said Hans Moritz Guenther, researcher at the MIT's Kavli Institute of Astrophysics and Space Research. , who led the study. "If our interpretation of the data is correct, this would be the first time we directly observe a young star devouring a planet or planets."
Previous graduation events of the 39, star could have been caused by similar disassemblies, either two planetary bodies or large remains of past collisions that met abruptly and separated again
RW Aur A is located in the Taurus-Auriga Dark Clouds , which house stellar nurseries containing thousands of infantile stars.Young stars, unlike our relatively mature sun, are still surrounded by a disq. and gas and tufts of rotating material, ranging from small grains of dust to pebbles, and perhaps nascent planets. These records last between 5 million and 10 million years
RW Aur A is estimated to be several million years old and is still surrounded by a disk of dust and gas. This star and its binary companion star, RW Aur B, are both about the same mass as the sun.
The notable declines in the optical brightness of RW Aur A that occurred for a few decades lasted about a month. Then, in 2011, the behavior changed. The star has further declined, this time for about six months. The star is finally cleared, and then disappear in mid-2014. In November 2016, the star came back to full brightness, then it dropped again in January 2017.
Chandra was used to observe the star during an optically brilliant period in 2013, then dark periods in 2015 and 2017, when one also observed a decrease in X-rays.
Because x-rays originate from the hot outside atmosphere of the star, changes in the ray spectrum X – the intensity of X-rays measured at different wavelengths – on these three observations were used to probe the density and composition of the absorbent material around the star.
The team found that the troughs in optical light and x-rays are caused by a dense gas obscuring the star's light. The observation in 2017 showed a strong emission of iron atoms, indicating that the disc contained at least 10 times more iron than in the 2013 observation during a brilliant period .
Guenther and his colleagues suggest that the excess of iron was planetary bodies, collided. If one or both planetary bodies are made partly of iron, their destruction could release a large amount of iron into the star disk and temporarily darken its light when the material falls into the sky. star
. grains or particles such as iron can be trapped in parts of a disc. If the structure of the disc changes abruptly, as when the star star's star passes nearby, the resulting tidal forces could release the trapped particles, creating an excess of iron that could fall into the body. 39; star.
from the star in the future, to see if the amount of iron that surrounds it has changed – a measure that could help researchers determine the size of the iron source. For example, if about the same amount of iron appears in a year or two, it may indicate that it comes from a relatively massive source.
"Much effort is currently being devoted to studying exoplanets and their formation – to see how young planets could be destroyed in interactions with their host stars and other young planets. and what factors determine if they survive, "says Guenther.
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