The International Space Station suffered a small leak of ammonia used to cool its power system on Thursday, but there was no danger to the crew, NASA said.

The U.S. space agency said crew had spotted small white flakes floating away from an area outside the craft before reporting the incident to Mission Control in Houston.

Sky-gazers were treated to an annular solar eclipse in remote areas of Australia on Friday, with the Moon crossing in front of the Sun to leave a "ring of fire" around its silhouette.

The eclipse, which occurs when the Moon passes between the Earth and the Sun but is too close to the Earth to completely cover the Sun, was seen in full across northern Australia, while Sydney saw a partial eclipse.

When Michael Gore stands, it's a triumph of science and engineering. Eleven years ago, Gore was paralyzed from the waist down in a workplace accident, yet he rises from his wheelchair and walks across the room with help from a lightweight wearable robot.

The technology has many nicknames. Besides "wearable robot," the inventions also are called "electronic legs" or "powered exoskeletons." This version, called Indego, is among several competing products being used and tested in U.S. rehab hospitals that hold promise not only for people such as Gore with spinal injuries, but also those recovering from strokes or afflicted with multiple sclerosis and cerebral palsy.

Beijing urged the European Union on Thursday to avoid engaging in protectionism, after Brussels proposed an anti-dumping levy on imports of Chinese solar panels.

The EU's executive arm, the European Commission, is considering a heavy tariff of 47 percent, an EU source told Agence France Presse, as European solar panel makers complain they are being undercut by cheap Chinese imports.

Scientists unveiled a new method on Wednesday for extracting metallic iron from its ore while curbing Earth-warming carbon dioxide emissions.

This is achieved with electrolysis and has the added benefit of releasing oxygen as a byproduct, a team from the Massachusetts Institute of Technology reported in the journal Nature.

For three quarters of an hour a giant swarm of locusts streams across the sky above southwest Madagascar.

Along National Route Seven, normally an artery for tourists enjoying breathtaking views of the island's vast open spaces, a 15 kilometre long (nine mile) swarm clouds the sky.

Landing astronauts safely on Mars is one of the biggest technological hurdles for any future manned mission to the Red Planet, even more complicated than last year's daring rover touchdown.

NASA dazzled observers by landing the one-ton Curiosity rover on Mars in August in a high-speed operation using a sky crane and supersonic parachute, but experts say the task would be even more challenging with humans onboard.

A community group that raised $1.3 million in a six-week online fundraising effort has purchased a laboratory once used by visionary scientist Nikola Tesla.

"We're feeling very excited and gratified that we've reached this milestone," said Jane Alcorn, president of the Tesla Science Center at Wardenclyffe, on New York's Long Island. Her group announced last week that it had finalized the purchase of the Tesla lab and property for $850,000.

The old coastal road in this fishing village at the eastern edge of Grenada sits under a couple of feet of murky saltwater, which regularly surges past a hastily-erected breakwater of truck tires and bundles of driftwood intended to hold back the Atlantic Ocean.

For Desmond Augustin and other fishermen living along the shorelines of the southern Caribbean island, there's nothing theoretical about the threat of rising sea levels.

Scientists say a disease destroying entire crops of cassava has spread out of East Africa into the heart of the continent, is attacking plants as far south as Angola and now threatens to move west into Nigeria, the world's biggest producer of the potato-like root that helps feed 500 million Africans.

"The extremely devastating results are already dramatic today but could be catastrophic tomorrow" if nothing is done to halt the Cassava Brown Streak Disease, or CBSD, scientist Claude Fauquet, co-founder of the Global Cassava Partnership for the 21st Century, told The Associated Press.