Physicists at the Technical University of Munich (tum) have found evidence of a supernova explosion near Earth (cosmic scale) about 2.5 million years ago. Supernovae usually occur at the end of the life of a star ten times more massive than our sun. Huge explosions produce heavy elements such as manganese. A team led by tum physicists has confirmed the presence of both fe-60 and mn-53 in the earth’s Manganese shell about 2.5 million years ago. The researchers said the increased concentration of Manganese-53 is clear evidence that supernovae did occur. < / P > < p > If a supernova occurs very close to the earth, it may cause great damage to the earth and any life on the earth at that time. However, this particular supernova is far enough away from earth that the only side effect is an increase in cosmic rays that lasts for thousands of years. Researchers Dr Thomas faestermann said that the increase in cosmic rays could lead to an increase in cloud formation, possibly related to the Pleistocene era (the ice age that began 2.6 million years ago). < / P > < p > generally on earth, manganese occurs only in the form of mn-55. Manganese-53 comes from cosmic dust, as found in the asteroid belt of the solar system. That kind of dust keeps hitting the earth, but there are few large dust spots on the earth. The researchers say the sediments on the seafloor preserve the distribution of elements in manganese crusts and sediment samples. < / P > < p > the team used an accelerator mass spectrometer to detect increased levels of iron-60 and Manganese-53 in layers deposited about 2.5 million years ago. The researchers point out that this is an investigative ultra trace analysis, and they’re talking about just a few atoms. However, the accelerator mass spectrometer is sensitive enough for scientists to calculate that the mass of the exploded star must be about 11 to 25 times the size of the sun. Global Tech

By ibmwl