Tigers change behavior to live near people

Tigers don't necessarily need huge dedicated reserves, say scientists, but can accommodate themselves to patterns of human activity by becoming more nocturnal.

Night lights used to track diseases

Satellite images of city lights can be used to monitor outbreaks of disease, says a team led by Princeton University.

Solar plane makes it safely through the night

Solar Impulse has successfully completed its first night flight, the first solar-powered plane to do so.

Solar powered plane soars over Swiss skies

The solar powered Impulse HB-SIA has successfully completed its maiden voyage over a picturesque Swiss airfield.