Scientists on Sunday said that methane which leaked from the 2010 oil-rig blowout in the Gulf of Mexico persisted in the sea for months beyond a presumed cleanup of the gas by marine microbes.

As much as half a million tonnes of natural gas, 80 percent of it methane, leaked into the deep sea as a result of the blowout on April 20, 2010, on BP's Deepwater Horizon rig.

Scientists on Sunday said they had used a harmless electrical current to modify sleep so that an individual has "lucid dreams," a particularly powerful form of dreaming.

The discovery provides insights into the mechanism of dreaming -- an area that has fascinated thinkers for millennia -- and may one day help treat mental illness and post-trauma nightmares, they said.

The global cost of securing a clean energy future is rising by the year, the International Energy Agency (IEA) warned Monday, estimating that an additional $44 trillion of investment was needed to meet 2050 carbon reduction targets.

Releasing its biennial "Energy Technology Perspectives" report in Seoul, the agency said electricity would increasingly power the world's economies in the decades to come, rivaling oil as the dominant energy carrier.

Winds in the wild Southern Ocean are blowing at their strongest in a millennia as climate change shifts weather patterns, leaving Antarctica colder and Australia facing more droughts, a study showed Monday.

Rising carbon dioxide levels in the atmosphere were strengthening the winds, already dubbed the "Roaring Forties" for their ferocity, and pushing them further south towards Antarctica, researchers from the Australian National University (ANU) said.

Thousands of vacuum-sealed plastic pouches filled with bits of bone rest in a Manhattan laboratory. These are the last unidentified fragments of the people who died in the World Trade Center on Sept. 11, 2001.

On Saturday, the 7,930 pouches are to be moved in a solemn procession from the city medical examiner's office to the new trade center site. They will be kept in a bedrock repository 70 feet underground in the new Sept. 11 Memorial Museum that opens May 21.

Cambodian customs officials are pictured with a haul of seized ivory at a port of Sihanoukville on May 9, 2014

Cambodian customs on Friday seized more than three tonnes of ivory -- the country's largest-ever haul of elephant tusks -- hidden in a container of beans.

Scientists have discovered 14 new species of so-called dancing frogs in the jungle mountains of southern India — just in time, they fear, to watch them fade away.

Indian biologists say they found the tiny acrobatic amphibians, which earned their name with the unusual kicks they use to attract mates, declining dramatically in number during the 12 years in which they chronicled the species through morphological descriptions and molecular DNA markers. They breed after the yearly monsoon in fast-rushing streams, but their habitat appears to be becoming increasingly dry.

The International Space Station is down one power channel because of an electrical malfunction. But NASA says everyone and everything is safe up there.

Mission Control says one of eight power channels went down Thursday because of an apparent trip in an electrical switch. Most of the station systems that depend on that power line immediately switched to a backup. Within an hour, flight controllers moved the remaining systems to the backup power channel.

Antarctic Treaty signatories made progress Wednesday towards future protection of the icy continent's marine life, NGO officials said.

Authorities at the treaty's annual meeting, in Brasilia this year, "sent a strong message of support" to the commission overseeing Antarctic wildlife protection, said Mark Epstein, director of the Antarctic and Southern Ocean Coalition. 

Radio waves disrupt the magnetic "compass" in robins, according to a study published on Wednesday that is likely to fuel debate about the safety of electronic devices.

In a long and careful experiment, German scientists found that migrating robins became disorientated when exposed to electromagnetic fields at levels far lower than the safety threshold for humans.