The Big Picture blog has started their photo-a-day countdown to Christmas this year, again using images from the Hubble Space Telescope. A new photo is added every day here.

I think Carl Sagan would approve. My dad loaned me the book Cosmos to go along with my watching of the show, and here’s my holiday thought for this season:

The Cosmos may be densely populated with intelligent beings. But the Darwinian lesson is clear: There will be no humans elsewhere. Only here. Only this small planet. We are a rare as well as an endangered species. Every one of us is, in the cosmic perspective, precious. If a human disagrees with you, let him live. In a hundred billion galaxies, you will not find another.