Skywatch

  • July 26, 2007

    Episode 111: Small Wonders

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    Shownotes

    New details about some of the interesting smaller objects in the solar system are shedding some light on the "planet controversy." Astronomers have been trying to establish what constitutes a planet, taking size, orbit and other factors into consideration. One of the important objects astronomers have been studying is Eris, discovered in 2005. Astronomers suspected Eris was bigger than Pluto, but now they know for sure that Eris has 1.27 times more mass that Pluto. Eris appears to have a density similar to Pluto's, and probably contains rocky material as well as ice. Another object of interest is the asteroid Ceres. Astronomers have imaged Ceres with the Hubble Space Telescope in preparation for the launch of the DAWN mission in 2007. DAWN will travel to and orbit Ceres as well as another large body in the asteroid belt between Mars and Jupiter - Vesta.