While there's still no evidence that life evolved on Mars, we now know that it at least could have.
Astronomers have found a new and more accurate way to measure the ages of huge groups of stars called globular clusters.
If the earth keeps accumulating mass, does that mean that the Earth's gravitational pull has been increasing?
Scientists have a new estimate for the geological age of one of Mercury's oldest regions.
One of the great mysteries: Does life exist elsewhere in the universe. Research has found that such planets may be more common, and much closer, than we think.
NASA's Curiosity rover has found evidence for life-supporting conditions on ancient Mars.
The Kepler space telescope has shown us that we live in a galaxy full of Earth-sized planets.
The European Space Agency's Venus Express orbiter discovered evidence of volcanic eruptions that occurred as recently as several thousand years ago.
Some simple sugars detected by astronomers, glycoaldehydes, are thought to be the basic building blocks of life.
Pluto was demoted to dwarf planet status, but it still has moons. This new moon, called P5 for now, is the fifth moon found orbiting Pluto.