Supernova Explosion Discovered From 2.5 Million Years Ago

Scientists have discovered that a massive supernova explosion likely occurred in Earth's vicinity 2.5 million years ago. Researchers have theories across the board on whether or not it links to the period of the Ice Ages or even bipedalism. In a new research paper from the Technical University of Munich, originally reported by Universe Today, a team of researchers led by Gunther Korschinek have discovered proof of a supernova explosion in the form of a very specific manganese isotope known as 53Mn. These isotopes were discovered in a chunk of manganese crust found on Earth and what makes them unique is that they can only be produced by a supernova. [ignvideo url="https://www.ign.com/videos/2019/04/10/scientists-have-revealed-the-first-photo-of-a-black-hole"] "The increased concentrations of manganese-53 can be taken as the 'smoking gun' — the ultimate proof that this supernova really did take place," Korschinek said in a press release related to the discovery.

What Is a Supernova?

Supernovae are massive explosions with the potential to sterilize or even destroy entire planets. They occur when a large star reaches the end of its life and the resulting explosion can light up nearby skies for months. Without actually seeing a supernova, scientists are able to discover one might have occurred through the large blast of chemicals the explosions release. These chemicals are blasted outwards and can form concentrations of isotopes in places like Earth's crust. Scientists have long pondered the idea that a supernova occurred in Earth's vicinity due to a concentration of an iron isotope known as 60Fe. This isotope is produced by supernovae, but scientists have never been sure that the 60Fe actually came from such an explosion, because 60Fe can also be produced by Asymptomatic Giant Branch stars. With the discovery of the 53Mn isotopes in ferromanganese crust samples on Earth, scientists also discovered 60Fe, and unlike 60Fe, 53Mn cannot be produced by AGB stars. This is why Korschinek's team believes a supernova explosion produced both isotopes. [caption id="attachment_2417621" align="alignnone" width="1041"] A Hubble Space Telescope image of supernova remnants discovered in 2017. Image credit: NASA.[/caption] "A feasible way to detect 53Mn in Earth's reservoirs is, as in the case of the finding of 60Fe, direct atom counting by accelerator mass spectrometry (AMS)," Korschinek said. Korschinek's team used AMS to detect 53Mn in samples of ferromanganese crust as AMS helped pick out this isotope among other very similar isotopes like 55Mn, which is more common to begin with as its the only "naturally occurring" manganese isotope. When the scientists discovered the 53Mn, they realized it was significantly abundant in concentration, too. This led the team to further believe it was the work of a supernova explosion that occurred about 2.5 million years ago. "This is investigative ultra-trace analysis," Korschinek said. "We are talking about merely a few atoms here. But, accelerator mass spectrometry is so sensitive that it even allows us to calculate from our measurements that the star that exploded must have had 11 to 25 times the size of the sun."

Did the Supernova Impact Earth?

The supernova explosion was too far away to cause something of a mass extinction for Earth, according to the team, but it likely caused a change in climate due to a shower of cosmic rays. "However, this can lead to increased cloud formation," research paper co-author Thomas Faestermann said. "Perhaps there is a link to the Pleistocene epoch, the period of the Ice Ages, which began 2.6 million years ago." [widget path="global/article/imagegallery" parameters="albumSlug=the-25-best-sci-fi-movies&captions=true"] Some researchers believe that the supernova might have led to a partial extinction known as the Pliocene Marine Megafauna extinction, while others believe a supernova like this one might have triggered humankind's conversion to bipedalism, according to Universe Today. The supernova's effects of life here on Earth is still a question of debate, but this new discovery of 53Mn provides even stronger evidence that a massive supernova explosion did occur within the Earth's vicinity 2.5 million years ago. Here's hoping Earth survives the next one, whenever that may be. If you're looking for more science stories, read about the black hole closest to Earth recently discovered and then check out this story about how Earth might be causing the Moon to rust. For something off world, read about possible signs of life discovered on Venus that date back to 1978 and then check out this story where scientists claim to have evidence of a parallel universe where time runs backward. [poilib element="accentDivider"] Wesley LeBlanc is a freelance news writer and guide maker for IGN. You can follow him on Twitter @LeBlancWes. 

from IGN News https://ift.tt/36D146X
via IFTTT