Near-death experiences are often thought of as mystical phenomena, but research is now revealing scientific explanations for virtually all of their common features. The details of what happens in near-death experiences are now known widely - a sense of being dead, a feeling that one's "soul" has left the body, a voyage toward a bright light, and a departure to another reality where love and bliss are all-encompassing.

Approximately 3 percent of the U.S. population says they have had a near-death experience, according to a Gallup poll. Near-death experiences are reported across cultures, with written records of them dating back to ancient Greece. Not all of these experiences actually coincide with brushes with death - one study of 58 patients who recounted near-death experiences found 30 were not actually in danger of dying, although most of them thought they were.

Recently, a host of studies has revealed potential underpinnings for all the elements of such experiences. "Many of the phenomena associated with near-death experiences can be biologically explained," says neuroscientist Dean Mobbs, at the University of Cambridge's Medical Research Council Cognition and Brain Sciences Unit. Mobbs and Caroline Watt at the University of Edinburgh detailed this research online August 17 in Trends in Cognitive Sciences.

We may have interbred with Neanderthals in the past, but only rarely was that sex successful in producing offspring, scientists now suggest.

Any such dalliances might either have been scarce or only rarely produced offspring, or both, researchers explained.

Recent analyses of Neanderthal genes revealed that many of us have this extinct lineage within our ancestry. Estimates suggest that Neanderthal DNA makes up 1 to 4 percent of modern Eurasian genomes.

To learn more, scientists designed a computer model that estimated how much Neanderthal ancestry would be present in modern humans based on different levels of interbreeding, simulating potential interactions after our ancestors expanded into Neanderthal territory from Africa starting about 50,000 years ago. They next applied this model on the level of Neanderthal DNA seen in modern French and Chinese groups.

Based on this data and model, the researchers discovered the interbreeding success rate was probably less than 2 percent in most scenarios. Assuming that both lineages interacted for about 10,000 years, this means successful interbreeding would have, on average, happened just once every 23 to 50 years, they calculated.

A key source of information about the health of the ozone layer above the Arctic looks set to be choked off.

In a year that saw the first genuine 'ozone hole' appear in the Northern Hemisphere, atmospheric scientists say they are shocked to learn that Environment Canada, the country's environment agency, has decided to drastically reduce its ozone science and monitoring programme.

Its network of monitoring stations provides about one-third of the Arctic's ozone measurements and this year contributed key data showing unprecedented depletion of stratospheric ozone over the Arctic. With regular in situ measurements going back to 1966, Canada also holds the longest-running record of atmospheric ozone levels in the world - an archive that is also threatened.

The Canadian observation network comprises 17 stations - from London, Ontario, in the south to Alert in the high Arctic - which use several techniques to measure ozone (see 'The ozone network'). But atmospheric scientists and research institutes around the world, including Canada, Britain, Switzerland and Germany, have been told, informally, that the network will be shut down as early as this coming winter. This will be the end of in situ ozone measurements, including those made by balloons launched at least once a week from 11 of the stations. "This is devastating for the whole field," says Tom Duck, who conducts atmospheric research at Dalhousie University in Halifax, Nova Scotia.

The HARPS spectrograph on the 3.6-metre telescope at ESO's La Silla Observatory in Chile is the world's most successful planet finder [1]. The HARPS team, led by Michel Mayor (University of Geneva, Switzerland), have announced the discovery of more than 50 new exoplanets orbiting nearby stars, including sixteen super-Earths [2]. This is the largest number of such planets ever announced at one time [3]. The new findings are being presented at a conference on Extreme Solar Systems where 350 exoplanet experts are meeting in Wyoming, USA.

"The harvest of discoveries from HARPS has exceeded all expectations and includes an exceptionally rich population of super-Earths and Neptune-type planets hosted by stars very similar to our Sun. And even better -- the new results show that the pace of discovery is accelerating," says Mayor.

In the eight years since it started surveying stars like the Sun using the radial velocity technique HARPS has been used to discover more than 150 new planets. About two thirds of all the known exoplanets with masses less than that of Neptune [4] were discovered by HARPS. These exceptional results are the fruit of several hundred nights of HARPS observations [5].

Working with HARPS observations of 376 Sun-like stars, astronomers have now also much improved the estimate of how likely it is that a star like the Sun is host to low-mass planets (as opposed to gaseous giants). They find that about 40% of such stars have at least one planet less massive than Saturn. The majority of exoplanets of Neptune mass or less appear to be in systems with multiple planets.

With upgrades to both hardware and software systems in progress, HARPS is being pushed to the next level of stability and sensitivity to search for rocky planets that could support life. Ten nearby stars similar to the Sun were selected for a new survey. These stars had already been observed by HARPS and are known to be suitable for extremely precise radial velocity measurements. After two years of work, the team of astronomers has discovered five new planets with masses less than five times that of Earth.

Mom and Dad warned that television would rot your brain, and a new study suggests it's true - at least from certain frenetic-style cartoons.

Kids who watched just nine minutes of the fast-paced children's cartoon SpongeBob SquarePants did worse afterward at tasks requiring focus and self-control than did kids who watched a slow-paced cartoon and kids who entertained themselves by coloring.

The study was small, and scientists weren't sure how long the brain-drain effect persists. But the research highlights the importance not just of how much TV a child watches, but of what kind, said Dimitri Christakis of the Seattle Children's Research Institute at the University of Washington. Christakis was not involved in the study, but penned an accompanying editorial appearing today (Sept. 12) in the journal Pediatrics.

"It's not ... all television that creates deficits in attention," Christakis told LiveScience. "It's the pacing of the program, what we call the 'formal features,' that actually matter."

Nautilus foresaw the Arab Spring and the whereabouts of Bin Laden (sort of). What happens next is anyone's guess

Hey, wouldn't it be great if we had a supercomputer that could predict the future? By "we", incidentally, I mean "we" as in "the human race", not "we" as in "myself and you - you specifically". You might be Josef Fritzl for all I know. I don't want to find myself sharing a supercomputer desktop with Fritzl. Every time I went to open a window, he'd nail it shut.

That's a massive digression for an opening paragraph, so let's pretend it didn't happen and start again, after I click my fingers. Since you won't be able to hear me click my fingers, I'll substitute a pound sign for the noise itself. Ready? 3 ... 2 ... 1 ... £!

Lightning discharges in the atmosphere are familiar, but what about the ones underground?

The electrical phenomenon we call lightning is not well understood. The most common interpretation involves the circulation of water vapor up and down through clouds in a process called convection. Water is heated by the Sun until it evaporates, rising into the air where it collects into clouds. The water vapor continues to rise higher and higher, finally cooling enough to condense back into liquid. Earth's gravity then pulls it back to the surface where the cycle repeats.

According to consensus opinions, water droplets tend to collide during convection, knocking electrons off one another, creating a charge separation. Electrons accumulate in the lower portion of the cloud, where it acquires a negative charge. As the droplets that have lost an electron continue to rise, they carry a positive charge into the top of the cloud.

A chemical essential for life may have been brought to Earth from outer space by meteorites, scientists claim.

Astrobiologist Dr Terry Kee, from the University of Leeds, has found meteorite fragments contain a precursor to a key chemical that allows biological cells to capture energy from their surroundings.

He believes debris from meteorites that hit the Earth billions of years ago may have combined with slightly acidic water on the planet to produce early forms of the compound.

This would then have allowed the first forms of cellular life to form and to use energy from their surroundings.

"There is strong scientific evidence that chemicals essential to life have been found in interstellar material such as meteorites," Dr Kee said.

"Meteorites are fragments of some of the oldest materials in our solar system, and their composition can hold clues as to the appearance and environment of our own planet and what lived on it billions of years ago."

The rewards outweigh the risks -- when you're in a group, anyway. A new USC study explains why people take stupid chances when all of their friends are watching that they would never take by themselves. According to the study, the human brain places more value on winning in a social setting than it does on winning when you're alone.

Georgio Coricelli of the USC Dornsife College of Letters, Arts and Sciences led a multinational team of researchers that measured activity in the regions of the brain associated with rewards and with social reasoning while participants in the study entered in lotteries.

Their study appears in the Proceedings of the National Academy of Sciences.

The researchers found that the striatum, a part of the brain associated with rewards, showed higher activity when a participant beat a peer in the lottery, as opposed to when the participant won while alone. The medial prefrontal cortex, a part of the brain associated with social reasoning, was more activated as well. Those participants who won in a social setting also tended to engage in more risky and competitive behavior in subsequent lotteries.

"These findings suggest that the brain is equipped with the ability to detect and encode social signals, make social signals salient, and then, use these signals to optimize future behavior," Coricelli said.

Feeling lazy? It may be in your genes, say McMaster University researchers.

A study with lab mice at the Hamilton, Ont., university suggests rodents who lack key muscle genes could not run as far as normal mice, who typically love to run.

"While the normal mice could run for miles, those without the genes in their muscle could only run the same distance as down the hall and back," Gregory Steinberg, associate professor of medicine in Michael G. DeGroote School of Medicine and Canada Research Chair in Metabolism and Obesity, said in a statement.