22 June 2025
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Radioactive ‘timers’ reveal likely source of galactic cosmic rays

22 April 2016 Astronomy Now

Most of the cosmic rays arriving at Earth from our galaxy come from nearby clusters of massive stars, according to new observations from NASA’s Advanced Composition Explorer (ACE) spacecraft. But the detection of a few radioactive cosmic-ray iron nuclei also indicates that there has been a supernova in our galactic neighbourhood within the last few million years.

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News Headlines

  • universe
    Is the Hubble Tension Resolved?
    9 June 2025
  • The Universe
    Universe’s end – sooner rather than later
    16 May 2025
  • T Coronae Borealis
    A faint star will reveal itself as it throws a hissy-fit
    26 March 2025
  • Saturn
    Saturn’s Rings to “Disappear”
    24 March 2025
  • Big Bang
    The Lithium Problem
    17 March 2025
  • Home
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      • August last issue
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