The mystery of strange cosmic radio rings that are larger than entire galaxies has been solved
The mysterious ring-shaped radio waves, which are larger than entire galaxies, may be galactic winds from stars that exploded billions of years ago. Such winds can travel at speeds of up to 2,000 kilometers per second.
This is stated in a study published in the journal Nature. Scientists have delved into the massive star galaxies that can control these superfast winds.
In 2019, the Australian telescope ASKAP (Australian Square Kilometer Array Pathfinder) discovered something no one had ever seen before: ring-shaped radio waves in space that were so large that they contained entire galaxies at their centers.
For example, the structure discovered was at least hundreds of kiloparsecs across, while our Milky Way galaxy is only 30 kiloparsecs across. One kiloparsec is equal to 3,260 light years.
Since then, scientists have tried to unravel the mystery of this phenomenon but have been unsuccessful. Now, a team of American astrophysicists has stated that such ring-shaped waves are shells formed by outflowing galactic winds that are the result of supernova explosions.
This theory was confirmed by computer simulations, which showed that such galactic winds can blow for more than 750 million years.
According to the scientists, exploding galaxies have an extremely high rate of star formation. When stars die and explode, they push gas from the star and its surroundings back into interstellar space.
If such explosions occur nearby and at about the same time, their force can push gas from the galaxy itself into outflowing winds that can reach speeds of 2,000 kilometers per second.
The simulations showed outflowing galactic winds blowing for 200 million years before they stopped. When the galactic wind stopped, the forward push continued to push high-temperature gas out of the galaxy and create a radio ring, while the backward push sent cooler gas falling back into the galaxy.
The researchers note that for this to work, a high rate of mass outflow is required, and the surrounding gas outside the galaxy must have a low density. Otherwise, the push will stop.
According to previous versions, scientists believed that such ring-shaped radio waves could come from planetary nebulae or even be the result of black hole mergers. However, no evidence of these theories was found.
Earlier, OBOZ.UA reported that scientists have solved the mystery of one of the strangest asteroids that was hiding in the sun.