Alicia Chang

National security warrants NASA background checks, judge says.

Two months after surviving a giant dust storm, one of NASA's martian rovers begins a risky drive into Victoria Crater.

Scientists believe heat from radioactive decay inside a tiny, icy Saturn moon shortly after it formed billions of years ago may explain why geysers are erupting from the surface today.

LOS ANGELES (AP) -- The astronomers who claim to have discovered the 10th planet in the solar system have another intriguing announcement: It has a moon