Ultrahigh-Energy Cosmic Rays – Local Origin?
Ultrahigh-energy cosmic rays (UHECRs) are the fastest moving objects ever found. If a ray of light travels through a void for 300 million years, and an UHECR travels on the same journey, light will get there a mere microsecond quicker.
Given the density of microwave radiation thought to fill the voids of space, scientists have been puzzled as to how the UHECRs are hitting Earth at full speed, without being slowed down by radiation (or anything else in their way).
According to Scientific American (April 2008, pages 14-15), the world’s largest array of cosmic ray detectors in Argentina has discovered that most UHECRs are coming from nearby galaxies. Strangely none are coming from the Virgo cluster of galaxies, only 60 million light years away.
One of the possible explanations is that super-massive black holes in Virgo are lacking the power of those in other nearby galaxies.
As usual, the super-massive black hole at the center of our own galaxy, and the capacity it may have to bombard us with cosmic rays, is not mentioned.
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