The universe is a stage of huge explosions of various kinds. These include stellar flares, where stars suddenly release magnetic energy; and neutron star mergers, where two dense stars collide. But one class of explosions outweigh the rest: Gamma ray bursts are the most energetic explosions observed in the universe.
Gamma rays are one of the most energetic forms of light, and gamma rays emit almost unimaginable amounts of them. First discovered during the Cold War – by military satellites searching for signs of nuclear tests in the upper atmosphere – gamma ray bursts are now thought to be caused by massive explosions caused by massive stars running out of fuel. These events are rare, but so energetic that they can be observed in galaxies several billion light years away.
Until recently, astronomers thought they had seen evidence of one of these explosions from the most distant galaxy. But a recently published paper casts doubt on these claims, suggesting that it may be due to a more mundane source much closer to home.
gamma ray burst
No gamma ray bursts have been documented in our galaxy yet, which is probably not a bad thing. A gamma ray pointed directly at Earth would probably lead to a mass extinction event, and the end of civilization as we know it. Unspecified events may actually have caused mass extinction events already in Earth’s history.
However, gamma ray bursts have been observed far away. The researchers suggested that researchers had discovered a new gamma ray burst in the farthest known galaxy. Posted in 2020. Using the Keck telescope on Mauna Kea, Hawaii, the researchers observed the stripes of the sky, and happened to see a bright flash, just a few seconds long, in one of their exposures.
By modeling the duration and brightness of the flash, they ruled out the possibility that it was a natural or man-made satellite close to home. He also ruled out several other astronomical explanations, and concluded that the most likely explanation was, in fact, a gamma ray burst.
What was so unique about this discovery was that the team pinpointed the direction of the event and found it to be coming from the same region known as GN-z11, the most distant and oldest galaxy near us. Is. found out so far.
Was it an incredible cosmic coincidence? Or was it an indication that gamma ray bursts were more common in the very early universe, just 400 million years after the Big Bang? The later findings would have major implications for our understanding of how stars and galaxies formed in the early universe, and caused much excitement among astronomers.
But unease about the group’s findings surfaced, with some arguing that it was far more likely that the flash was from an object within our solar system, which could be a natural (such as the Moon) or artificial satellite. In another paper, a different team suggested that the most likely explanation was a reflection from a man-made satellite. The original authors followed up on these claims, doubling down on their gamma ray burst interpretation, but the chorus of skeptics was only getting louder.
space junk
Now, the controversy has taken another turn, with a new paper recently published in Nature. The authors of this paper suggest that the alleged gamma-ray burst was actually a flash caused by a man-made satellite. Researchers used a public space-track website to search for potential human satellite interference in the direction and at the time of flash detection.
Krzysztof Kaminski, Adam Mickiewicz University in Poznan
Around the time that the original team was studying the sky, a Russian Proton rocket reached low-Earth orbit and released its upper stages (called Breeze-M), which then became space junk, which became Earth’s orbit. was circumambulating. By observing the orbit of the space debris and matching it with observations taken in the original study, the new team found that the flash could be easily explained by an upper stage falling over the part of the sky that the telescope was observing.
Read more: The Sun’s atmosphere is hundreds of times hotter than its surface – here’s why
The Proton rocket has been in operation since the 1960s, and this isn’t the only time one of its Breeze-M upper stages has been in the news. An explosion in 2013 scattered massive amounts of debris into Earth’s orbit, and left NASA to assess whether it would pose a threat to the International Space Station.
While this particular event was perhaps particularly ominous, with the increasing amount of junk in space, and the launch of large constellations of satellites by private company SpaceX and others in the years to come, it highlights the growing difficulties that astronomers face. to be viewed from the surface of the earth.
Better databases of satellites and space debris will help avoid this type of misidentification. But rising light pollution from satellite constellations is also threatening the ability of on-the-ground telescopes to even see clearly enough to do world-leading science.
This article is republished from – The Conversation – Read the – original article.
