UNITED STATES (OBSERVATORY NEWS) — Every month, meteors break through the interstellar abysses into the Earth’s atmosphere at sublight (!) Speeds. Space cataclysms disperse them: supernova explosions. Scientists who have made such amazing conclusions suggest ways to find traces of space guests.
Details are set out in a scientific article for publication in the Astrophysical Journal. In the meantime, you can familiarize yourself with her preprint.
Last year, Amir Siraj ( Amir Siraj ) and Abraham Loeb from Harvard University announced the discovery of the first interstellar meteor. Now the same authors went further. In a new work, they analyze the hypothesis that some of these bodies enter the atmosphere at a speed of 1% light.
What forces can disperse an ordinary stone to such an extent? The authors suggest that these are shock waves from supernova explosions.
Let us explain that on Earth there are such heavy elements as gold and uranium. They do not form in the stars. Experts believe that such atomic nuclei are synthesized mainly in supernova explosions (although collisions of neutron stars can play a significant role).
“We know that supernovae emit a significant amount of dust on the sub relativistic (ie sub-light – ed.). Speed” – says Siraj in the material Universe Today.
At the same time, observers see certain signs that part of this dust (although it is not known which one) is sent to the Universe in the form of lumps of millimeter or centimeter size.
“If at least 0.01% [mass] of the dust emission is contained in objects of a millimeter or larger, we expect that every month a sub relativistic meteor will appear in the Earth’s atmosphere – based on the frequency of supernova explosions in the Milky Way galaxy,” the scientist says.
Loeb and Siraj are not the only specialists to come to such conclusions. The hypothesis of the existence of sunlight meteors of millimeter size has previously been expressed by several astronomers. Among them, by the way, was the great Lyman Spitzer, in whose honor the famous space telescope was named .
Why then do we not know anything about the existence of such “guests”? Because, oddly enough, they never tried to find out.
“Meteors usually travel at a speed of about 0.01% of the speed of light,” Siraj explains. “Therefore, the current [search methods] are set to search for signals from objects moving at that speed.”
Bodies flying a hundred times faster simply elude existing surveillance systems, the expert explains.
In this regard, Siraj and Loeb wondered what phenomena would accompany the contact of such haste with the air ocean of the planet. To do this, they developed a model of a cloud of red-hot plasma, which is formed around a sublight meteor due to friction against air.
Scientists have found that a flash of light and a sound shock wave should warn of an interstellar visit to earthlings. Both phenomena last about a tenth of a millisecond.
Moreover, they are quite accessible for observation at the current technological level. So, a suitable optical detector measuring just one square centimeter (!) Is capable of capturing a flash from the combustion of a millimeter sublight meteor. High-speed infrasound microphones will help in shock wave detection.
According to the authors, a global network of only 600 detectors, covering the entire sky, is able to capture several such events a year.
It is also possible that such a network already exists. According to experts, the equipment servicing the CNEOS meteor and fireball database could well cope with this task.
Another thing is that the results of observations of flares and explosions with characteristics of interest to the authors … are simply classified. Siraj and Loeb urge the US government to declassify this data so as not to force astronomers to create a duplicate network.
This article is written and prepared by our foreign editors writing for OBSERVATORY NEWS from different countries around the world – material edited and published by OBSERVATORY staff in our newsroom.
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