Dwarfs vs Planets

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Today I had a nice surprise. One of my old friends and his colleagues published an article at the prestigious journal Nature. So this make a nice first entry for my blog. Here is the editor's summary:

Four trans-Neptunian objects are currently recognized as dwarf planets: Eris, Haumea, Makemake and Pluto. Of these, the 'demoted' planet Pluto has been studied for many years and has a detected atmosphere. The others are difficult to observe because of their extreme distance from the Sun, but a stellar occultation event on 6 November 2010 provided an opportunity for a closer look at Eris. The data obtained reveal Eris as a 'twin' for Pluto in terms of size, and previous work showed the two to have similar surface compositions. Eris, however, has no detectable atmosphere and its surface is bright, possibly a result of atmospheric collapse in an extremely cold environment.

I must admit that I was not aware of the 4 dwarf planets, even though I remember when the IAU (International Astronomical Union) decided to 'demote' Pluto from its planet status.

This is significant for me because my friend W. Corradi was the only professor at the physics department to encourage and support an iniciative of some crazy engineering students that decided to build their own radiotelecope from scratch. I may talk more about this sometime. For now you can take a look at the original article from Nature or a digest form National Geographic Daily News.