Deep-Sea Fossils Yield Traces of a 2 million-year-old Supernova
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April 17, 2013

Deep-Sea Fossils Yield Traces of a 2 million-year-old Supernova

 

 

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If Shawn Bishop, a physicist at the Technical University of Munich, is correct about a certain iron-loving deep-sea bacteria, then their fossilized remains hold iron traces from a supernova that exploded 2.2 million years ago possibly in the Scorpius–Centaurus  Association (above), the closest stellar association to our solar system, at a distance of about 130 parsecs (424 light years) from the Sun.

The fossil find would be the first biological signature of an exploding star found on Earth, Nature reports. Bishop based his research on the 2004 findings of the radioactive isotope iron-60, which does not form on Earth, in a chunk of sea floor from the acquired parts of a sediment core from the eastern equatorial Pacific Ocean. The scientists who discovered the iron-60 concluded it must have come from the ancient supernova.

"This apparent signal of iron-60," Bishop said, :could be the remains of magnetite (Fe3O4) chains formed by bacteria on the sea floor as radioactive supernova debris showered on them from the atmosphere, after crossing inter-stellar space at nearly the speed of light."

Bishop and colleagues gathered samples of ocean core dating between 1.7 and 3.3 million years ago and took samples every 100,000 years in the rock, treating the samples with chemicals that would isolate only the iron-60. The only strata they could find traces of the iron-60 was in sediment samples dated around 2.2 million years old.

The wide field X-ray image of the Scorpius-Centaurus association above was constructed from the data of the ROSAT All Sky Survey Background maps. The yellow dots mark the positions of bright X-ray sources detected in the survey (only about 10% of the brightest X-ray sources are shown). The blue circles mark the three subgroups Upper Scorpius, Upper Centaurus-Lupus, and Lower Centaurus-Crux (from left to right).

The Daily Galaxy via Nature.com

Comments

What is exactly "radioactive supernova debris"?
It sounds like it is matter and not electromagnetic radiation.
And if it is matter how can it travel at the speed of light?
Thank you and I hope for a reply.

Read it again. The term used was nearly the speed of light, which is indeed possible ; especially if we're talking charged particles which can be accelerated by electromagnetic fields. Any debris would probably be ionized and moving at high velocities, but wouldn't necessarily be radioactive.


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