Monday, October 22, 2007


This is a NASA's Hubble Space Telescope color image of Ceres, the largest Main Belt asteroid and one of the three known dwarf planets of the Solar System. At 18 km/pixel, this is probably the best picture currently available of this world. Don't be fooled by the light appearance -the image is actually contrast-enhanced to show features, Ceres by itself absorbs 91% of light falling on it. The Dawn Mission is going to show us better pictures in 2015.

Saturday, October 20, 2007

An healthy mouse challenges genome evolution models.

Why is this mouse healthy? Scientists know that genomes of mammals share DNA sequences whose function is unknown, but that are perfectly conserved between species. It seems natural to think those sequences must be somehow vital to the organism, since tens of million years of evolution didn't touch them. Yet when they deleted one of them (herein printed under the mice) from the genome of some mice, they found that no apparent side effect happens. What is the role, then, of these sequences?

Read the full story on PLoS Biology.