In the powerful, fast-fading realm of gamma-ray bursts, scientists say they have detected for the first time a lingering afterglow of the shortest types of bursts, which themselves disappear within a second.

This afterglow, radiating in X rays, may provide crucial insight into what triggers the mysterious bursts, the most energetic explosions in the Universe, second only to the big bang in total power. Previously, scientists had only detected the afterglow of longer bursts, which can last fr

Interstellar travellers should be “motivated, tolerant and nice”.

One hundred and sixty fertile, motivated, English speakers could make it to distant stars, researchers have worked out. But generations down the line, returning voyagers may speak an alien tongue.

Travel to planets orbiting other stars will soon be technically possible, the meeting of the American Association for the Advancement of Sciences in Boston heard last week. But the 200-year odyssey will require a cer

Sophisticated jewellery appeared with social events.

Our early ancestors glammed-up for a get-together. Humans worldwide began wearing jewellery at the same time as groups started meeting up, say US researchers. The finding counters the idea that ’modern’ behaviour swept the globe when modern humans migrated out of Africa.

Mary Stiner and her colleagues unearthed ancient necklaces at three sites in Asia, Africa and Europe. Residents of Kenya around 40,000 years ago

Bleak forecast for sea level in 2100.

Sea level could rise by up to 30 centimetres over the next century, a new estimate predicts. That’s almost twice as much as the Intergovernmental Panel on Climate Change (IPCC) projected last year.

“My grandchildren will almost certainly be affected,” says Mark Meier of the University of Colorado, Boulder, who made the revised estimate. Such a rise could push shorelines back by 30 metres, he said, flooding coasts and submerging islands.

Obesity epidemic sweeps into developing world

Obesity is spreading to all corners of the globe, researchers warned the meeting of the American Association for the Advancement of Science in Boston. Sedentary lifestyles and fast food are causing previously unaffected populations to fall foul of fat.

“Obesity is no longer confined to Western, industrialized societies,” said anthropologist Marquisa LaVelle of the University of Rhode Island, Providence. Guatemalans in the United S

Match up folds to fight stubborn paper.

No road journey is complete without a wrestle with the map. Now a US computer scientist has worked out why the map usually wins.

Erik Demaine of the Massachusetts Institute of Technology in Cambridge has come up with an origami algorithm that predicts when a stubborn street plan will be re-foldable. “It’s the meeting of paper folding and computer science,” he says.

The rules governing whether a sheet of paper divided into a g