Scientists are developing a salt-resistant variety of rice. The move was prompted, in part, by last year's Japan tsunami, which flooded some 20,000 hectares of rice paddies. The rice varieties Japanese farmers were growing in those paddies couldn't survive in salt-contaminated soil. Those ruined paddies might be the first to test out the new rice-growing techniques.

Astronomers using data from Kepler mission have discovered the three smallest planets yet detected orbiting a star beyond our sun. The planets orbit a single star, called KOI-961, and are 0.78, 0.73 and 0.57 times the radius of Earth. The smallest is about the size of Mars.

Vitamin D may help prevent hormonal changes that can lead to bone loss among those being treated for HIV with the drug tenofovir, according to the results of a National Institutes of Health network study of adolescents with HIV.