NASA has scheduled a press conference for tomorrow morning at 9:00am PDT, and you should all watch it. The announcement has to do with a new Kepler discovery. Kepler is a space telescope that is responsible for finding over a thousand confirmed extrasolar planets, or planets orbiting other stars. The new findings will very likely be the most Earth-like planet found to date.
The press conference can be watched live here:
Best-case scenario? Kepler has found an Earth-like planet whose atmosphere has a high concentration of dioxygen, or O2, which did not exist on Earth until the evolution of photosynthesis. Since O2 is not produced in stellar reactions (elemental oxygen is, but not molecular oxygen) or in large quantities by other known natural processes, the presence of the molecule on another planet would be a strong indicator of life.