Discovery of iron-60 and manganese-53 substantiates supernova 2.5 million years in the past.
When the brightness of the star Betelgeuse dropped dramatically just a few months in the past, some observers suspected an impending supernova – a stellar explosion that would additionally trigger harm on Earth. While Betelgeuse has returned to regular, physicists from the Technical University of Munich (TUM) have discovered proof of a supernova that exploded close to the Earth round 2.5 million years in the past.
The lifetime of stars with a mass greater than ten instances that of our solar ends in a supernova, a colossal stellar explosion. This explosion results in the formation of iron, manganese, and different heavy parts.
In layers of a manganese crust which might be round two and a half million years outdated a analysis staff led by physicists from the Technical University of Munich has now confirmed the existence of each iron-60 and manganese-53.”The elevated concentrations of manganese-53 might be taken because the “smoking gun” – the last word proof that this supernova actually did happen,” says first writer Dr. Gunther Korschinek.
Typically, manganese happens on earth as manganese-55. Manganese-53, however, normally stems from cosmic mud, like that discovered within the asteroid belt of our photo voltaic system. This mud rains down onto the earth repeatedly; however solely not often will we understand bigger specks of mud that glow as meteorites.
New sediment layers that accumulate 12 months for 12 months on the ocean flooring protect the distribution of the weather in manganese crusts and sediment samples. Using accelerator mass spectrometry, the staff of scientists has now detected each iron-60 and elevated ranges of manganese-53 in layers that have been deposited about two and a half million years in the past.
“This is investigative ultra-trace analysis,” says Korschinek. “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 around 11 to 25 times the size of the sun.”
The researchers have been additionally in a position to decide the half-life of manganese-53 from comparisons to different nuclides and the age of the samples. The consequence: 3.7 million years. To date, there has solely been a single measurement to this finish worldwide.
Reference: “Supernova-Produced 53Mn on Earth” by G. Korschinek, T. Faestermann, M. Poutivtsev, A. Arazi, Ok. Knie, G. Rugel, and A. Wallner, 17 July 2020, Physics Review Letters.
The analysis was funded by the German Research Foundation as a part of the Cluster of Excellence “Origin and Structure of the Universe”. In addition to the Technical University of Munich, the Laboratorio TANDAR, the Comisión Nacional de Energía Atómica, San Martín (Argentina), the Consejo Nacional de Investigaciones Científicas y Tecnicas (CONICET), Buenos Aires (Argentina) and the Helmholtz Center in Dresden-Rossendorf have been participated within the analysis.