Echoes of Ancient Supernova

In the year 1572, a new heavenly body appeared in the sky, shattering astronomers' (astrologers', actually) notions of the universe. The star appeared in the constellation Cassiopeia and was even visible during the day. Danish skygazer, Tycho Brahe, recorded the event in his book, Stella Nova. Its appearance challenged the idea that stars were unchangeable - a notion which was forwarded by Aristotle and his acolytes and dominated Western thought. Now scientists have uncovered "fossil evidence" of the supernova Brahe first observed and recorded.

Using telescopes in Hawaii and Spain, scientists picked up echoes from the supernova reflected by interstellar dust. The debris has expanded over the years into a cloud of dust approximately 20 light years in diameter. Brahe recorded the first light wave to pass Earth, but even today, light waves from the explosion reach us. These "echoes" create what are essentially fossil imprints which allow researchers to reconstruct the original explosion.

The BBC has more information on this discovery, along with video.

© C Harris Lynn, 2008