The light from a dying star is so intense that it can turn asteroids into dust.
New research shows this will happen to most stars currently burning in the universe, including the Sun, which will destroy its asteroid belt in about 5-6 billion years.
According to simulations, the only cause of this massive destruction would be electromagnetic radiation, and it is associated with the Yarkovsky-O'Keefe-Radzievsky-Paddak Effect (YORP), named after four scientists who contributed to its understanding.
The YORP effect occurs when the heat of a star alters the rotation of a small object in the Solar System, such as an asteroid.
The sun's light energy is absorbed by the asteroid, heating it up. Heat penetrates the rock until it is again radiated in different directions in the form of thermal radiation.
This blowout generates a small amount of thrust; over short periods of time, this will not affect anything, but over longer periods the effect will lead to a change in the rotation rate or deviation of the asteroid from the axis.
The phenomenon of falling asteroids is one of the ways in which we can observe this process today. But as the Sun develops, the effect will become more pronounced.
When main sequence stars such as the Sun enter the red giant stage, they expand to become very large and very bright. This stage lasts only a few million years, after the outer layers are shed, leaving a dense, dead star called a white dwarf.
For the Sun, this process will begin in about 5 or 6 billion years (mark this on your calendar).
“When a typical star reaches the giant stage, its luminosity rises from 1000 to 10,000 times that of our Sun,” explained astrophysicist Dmitry Veras of the University of Warwick.
'The star then collapses very quickly into a white dwarf the size of the Earth, its glow falling.' Hence, the YORP effect is very important during the giant phase, but hardly occurs after the star has turned into a white dwarf. '
Due to the initially increased brightness, the YORP effect will also increase. And most asteroids are not dense chunks of rock; these are loose, low-density conglomerates, cut with air pockets.
According to the team's computer simulations, the YORP effect would turn most of the asteroids into dust.
This will not happen with objects of higher structural integrity such as dwarf planets (so Pluto is safe!). But the asteroid belt has a different fate.
'The YORP effect in stellar systems is very strong and acts quickly, on the order of a million years. Not only will our own asteroid belt be destroyed, but also planets. And only thanks to the light of our Sun. '
This is proven not only by computer simulations. Our observations of white dwarfs show us this in practice.
The study was published in the Royal Astronomical Society's Monthly Notices.
Sources: Photo: NASA / JPL-Caltech
