First came the gravitational waves. Then, a burst of gamma radiation. As night fell in Chile, a small telescope had pinpointed the signals in the sky: the first ever neutron star smash-up found with gravitational waves.

Hours after the first signal in the Laser Interferometer Gravitational-Wave Observatory (LIGO) detector in Hanford, Washington, on 17 August, about 70 telescopes and observatories across the planet and in space turned in concert to face the same spot in the constellation Hydra.

Illustration of colliding neutron stars

“I don’t think it’s out of the question that this is the most observed astronomical event ever. It’s a thrilling notion, and a little overwhelming,” says LIGO spokesperson David Shoemaker. “We’ve got somewhere between a quarter and a third of all the world’s astronomers working with us.”

It marks the first gravitational waves from something other than a black hole binary, the first proof that neutron star mergers can cause gamma ray bursts, the first sighting of heavy elements being formed and the first measurement of the universe’s expansion using gravitational waves.

Since it first started listening for disturbances in space-time, LIGO has heard five signals from gravitational wavescreated as pairs of black holes merged and sent ripples throughout the universe, but none from any other cosmic characters.

“We’d always thought that we would see binary neutron stars first and we finally and it was every bit as spectacular as we hoped,” says Nelson Christensen at Carleton College in Minnesota.



A rare sighting of a chimpanzee giving birth in the wild came to a grisly conclusion. Within seconds of the birth, the baby was snatched away and eaten by a male of the same group. The observation explains why female chimpanzees tend to go into hiding for weeks or months when they have their babies.

Little is known about how chimpanzees give birth in the wild because only five births have ever been observed, says Hitonaru Nishie of Kyoto University in Japan. Nishie and his colleagues have been studying chimpanzees in Tanzania’s Mahale mountains for the last few years.

The mother chimp in the story holds an infant she subequently had

One of the reasons so few have been witnessed is that the soon-to-be mothers often leave the group when the baby is due, and don’t return until the infant is weeks or months old. This absence has been described as a chimpanzee’s “maternity leave”.

So Nishie and his colleague Michio Nakamura were surprised when, at around 11 am one December day, a female member of the chimpanzee group they were observing began to give birth in front of the 20 other members.

As soon as the baby was out – and before the mother had even had a chance to touch it – the baby was snatched away by a male member of the group, who then disappeared into the bush. The researchers found him around 1½ hours later, sitting up a tree and eating the infant from the lower half of its body. He ate the entire body within an hour.


Fancy a flutter? The chances of making a profit by betting on football matches are extremely low, but a trio of researchers has managed to beat the odds with a simple formula.

Mathematicians had already developed bookie-beating models that attempt to predict the outcome of sports matches, but they are difficult to devise and don’t always perform consistently. Lisandro Kaunitz at the University of Tokyo and his colleagues wanted to know if a more direct approach would work: using the bookmakers’ own odds against them.

Man sits at betting machines

The team studied 10 years’ worth of data on nearly half a million football matches and the associated odds offered by 32 bookmakers between January 2005 and June 2015. For every game, they looked for odds that might yield a better return than the average offered by bookies – say, 5 to 1 versus a mean of 2 to 1.

“Using the odds that are published, you can get a very good estimate of an event occurring,” says team member Javier Kreiner, a data scientist at transport start-up CargoX in São Paulo, Brazil. “What’s the probability of Barcelona winning against Real Madrid, for example.”

Mean odds of 2 to 1 suggest the bookies collectively think this reflects fair odds for that outcome. But 5 to 1 offers higher returns should the outcome materialise. The team used the historical data to work out the optimal distance from the mean odds – the one that would give a positive payout for the largest number of games.

When they applied their strategy in a simulation, they made a return of 3.5 per cent. Making bets randomly resulted in a loss of 3.32 per cent.


The sun could be one of our biggest threats in the next 100 years. If an enormous solar flare like the one that hit Earth 150 years ago struck us today, it could knock out our electrical grids, satellite communications and the internet. A new study finds that such an event is likely within the next century.

“The sun is usually thought of as a friend and the source of life, but it could also be the opposite,” says Avi Loeb at Harvard University. “It just depends on circumstances.”

Loeb and Manasvi Lingam, also at Harvard, examined data on other sun-like stars to see how likely solar “superflares” are and how they might affect us.

Solar flare

They found that the most extreme superflares are likely to occur on a star like our sun about every 20 million years. The worst of these energetic bursts of ultraviolet radiation and high-energy charged particles could destroy our ozone layer, cause DNA mutations and disrupt ecosystems.

But in the shorter term, the researchers say that less intense superflares of a type we know can happen on our sun could still cause problems. In 1859, a powerful solar storm sent enormous flares towards Earth in the first recorded event of its kind. Telegraph systems across the Western world failed, with some reports of operators receiving shocks from the huge amounts of electrical current forced through the wires.

Back then, there was not very much technology so the damage was not very significant, but if it happened in the modern world, the damage could be trillions of dollars,” says Loeb. “A flare like that today could shut down all the power grids, all the computers, all the cooling systems on nuclear reactors. A lot of things could go bad.”

Loeb says an event as powerful as the 1859 one could cause about $10 trillion of damage to power grids, satellites and communications. A flare just a bit stronger could even damage the ozone layer


Would you ride in a car that was prepared to kill you? An “ethical knob” could let the owners of self-driving cars choose their car’s ethical setting. You could set the car to sacrifice you for the survival of others, or even to always sacrifice others to save yodau.

A woman in a driverless car

The dilemma of how self-driving cars should tackle moral decisions is one of the major problems facing manufacturers. When humans drive cars, instinct governs our reaction to danger. When fatal crashes occur, it is usually clear who is responsible.

But if cars are to drive themselves, they cannot rely on instinct, they must rely on code. And when the worst happens will it be the software engineers, the manufacturers or the car owner who is ultimately responsible?

People’s attitudes to the issue are also complicated. A 2015 study found that most people think a driver less car should be utilitarian, taking actions to Minimise the amount of overall harm, which might mean sacrificing its own passengers in certain situations. But while people agreed to this in principle, they also said they would never get in a car that was prepared to kill them.


Psilocybin  a hallucinogenic compound found in magic mushrooms, may help re-set the activity of neural circuits in the brain that are involved in depression. Magic mushroom enthusiasts have long believed that the drug’s ability to induce profound-feeling experiences could be therapeutically useful. Brain-imaging studies have shown that psilocybin targets areas of the brain overactive in depression.

A hand holding mushrooms

Last year, Robin Carhart-Harris of Imperial College London and his colleagues conducted the first clinical trial of using psilocybin to treat depression, and got some encouraging results. The trial only involved 12 people and no control group, but the team found that after two sessions of psilocybin-assisted psychotherapy, all of the volunteers had reduced symptoms.

Now Carhart-Harris and his team have shown that psilocybin seems to cause changes in the brains of people with depression. The study involved 19 people who had depression that had not been helped by conventional treatments.

Each volunteer was given a 10 mg and 25 mg dose of psilocybin, seven days apart. Brain scans showed that, after taking the drug, activity in some regions of the brain reduced. These areas included the amygdala, which plays a role in processing stress and fear. The participants reported an immediate improvement in mood that lasted for up to five weeks.


A sperm age calculator can tell men how “old” their sperm are, using clues from DNA analysis, and has revealed some of the effects of smoking on sperm.

Sperm cells

While a woman’s age has long been known to affect the health of her offspring, we have only recently begun to understand how a father’s age can have similar effects. Older fathers are now known to pass on more genetic mutations to their children than older mothers do. And children of older fathers are more likely to have autism and schizophrenia.

“The hope is that we could potentially screen people and say, ‘your sperm is really old’, and identify risks for the offspring,” says Tim Jenkins at the University of Utah.

Growing evidence suggests that older dads might pass on health risks through epigenetic tags on the DNA in their sperm. These tags alter how active genes are, and lifestyle factors such as diet and smoking are known to make epigenetic changes that may affect the next generation.