Science review of 2011: the year's 10 biggest stories

Neutrino particles appeared to prove Einstein wrong by travelling faster than light, while the discovery of an Earth-like planet raised hopes of finding life on another world

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An artist’s impression of Curiosity, Nasa’s Mars-bound science lab, as it analyses Martian rock. Photograph: Reuters

Graphene is going to be the 'it' material of the 21st century

Or at least that is what George Osborne hopes. After two Manchester University scientists, Konstantin Novoselov and Andre Geim, won the 2010 Nobel prize for physics for their graphene research, the chancellor announced in the autumn that Britain would be investing £50m in setting up a national research programme into the substance. Graphene – a sheet of carbon atoms one atom thick – could be used to make everything from touchscreens to plastics cheaper and more efficient, say scientists, though such developments may take decades to achieve.Certainly much has been made of its potential. According to research carried out by James Hone of Columbia University, graphene is the strongest material ever measured, some 200 times stronger than structural steel. "It would take an elephant, balanced on a pencil, to break through a sheet of graphene the thickness of cling film," he told the BBC. However, it is the versatility of graphene – a possible source for composite materials, electronic components and other goods – that causes the excitement. As Geim says: "It is not even one material. It is a huge range of materials." Hence the billions that IBM, Samsung and Nokia are putting into graphene research, a commitment that puts Osborne's £50m investment into perspective.

Flying faster than the speed of light just might be possible after all

Despite Einstein assuring us a century ago that no moving object could surpass the velocity of light, scientists this year appear to have found an anomaly to the rule. In September, physicists at Cern in Geneva fired a beam of neutrinos – tiny entities that barely weigh anything, and which hardly ever interact with anything – to colleagues at the Gran Sasso laboratory 454 miles away in Italy. To their considerable surprise, the scientists found the neutrinos arrived so quickly, they must have been travelling faster than light, albeit only slightly – about 60 billionths of a second quicker. Most experts thought that the experiment would be proved flawed when it was repeated. However, a second firing of a beam of neutrinos produced a similar result. This leaves Professor Jim Al-Khalili, of Surrey University, facing the prospect of an uncomfortable new year. The physicist has pledged to "eat his shorts" live on TV if it is proved that neutrinos can travel faster than light.

Modern humans have been hanging around Europe for thousands of years longer than we had thought

Bones and teeth found in England and Italy have pushed back the dates for the arrival of modern humans in Europe by 5,000 years or so, researchers revealed. Two baby teeth, found in the Grotta del Cavallo, Apulia, and a jawbone fragment, from Kents Cavern, Devon, were dated as being 45,000 and 41,000 years old respectively, according to articles published in Nature. Previously it was thought that Homo sapiens arrived in Europe around 35,000 to 40,000 years ago, just when the Neanderthals – who had ruled the continent for several hundred thousand years – began to die out. If humans were responsible for replacing Neanderthals, they must have worked very fast, palaeontologists argued. However, these new dates increase the overlap of modern humans and Neanderthals, according to Dr Tom Higham, from Oxford University, who led the study at Kents Cavern. "We estimate that probably 3,000-5,000 years of time is the amount of the overlap," he told the BBC. Thus humanity had a comfortable period of several millennia to wipe out the Neanderthals, it now transpires.

The female brain lights up in a very special way after an orgasm

Last month, scientists revealed that they had used scanning images to create the world's first movie of the female brain as it approached, experienced and recovered from an orgasm. The animation showed the steady build-up of activity as disparate bunches of neurones flickered into life and then came together in a crescendo of activity before gently settling back down again as a test subject brought herself to orgasm. According to Professor Barry Komisaruk, a psychologist at Rutgers University in New Jersey, whose team carried out the research, the findings should lead to treatments that could help both men and women who cannot reach sexual climax. Kayt Sukel, whose orgasm was recorded by the Rutgers team, told the Guardian that she managed to stimulate herself despite having to lie still inside the dark, cramped confines of a MRI scanner. "If you move too much during an MRI scan you can compromise the data," she said. "It wasn't easy to work up to an orgasm but I found it wasn't quite as difficult as I had imagined." The earth moved, but not very much, in other words.

The best candidate for finding life on another world has been pinpointed by astronomers

Observations by the US space telescope Kepler pinpointed a planet orbiting another sun that is the closest thing to another Earth that has been detected to date. Kepler 22-b is about 2.4 times the size of Earth and lies in the so-called "Goldilocks zone" around its home star. In other words conditions there are not too hot and not too cold. Indeed, scientists estimate that the planet's surface temperature is a relatively balmy 22C while a year there that lasts 290 Earth days. Astronomers also speculate that Kepler 22-b possesses water. "This is a major milestone on the road to finding Earth's twin," said Douglas Hudgins, Kepler program scientist at Nasa headquarters in Washington. However, prospects for visiting the planet are remote. Kepler 22-b is 600 light years from Earth. Even having a radio conversation with any inhabitants that it might possess will be frustrating. At that distance, a radio message asking inhabitants how they are doing would not receive a reply for another 1,200 years.

You can win the Nobel prize even though you are dead

One of the strictest rules established by the committee that implemented Alfred Nobel's bequest for the science prizes was the edict that only the living receive an honour. "Work by a person since deceased shall not be considered," it states. But on 3 October, the Nobel committee announced that Ralph Steinman had won the prize for medicine, unaware that the Canadian immunologist had died of cancer the previous Friday. After a quick look at the rulebook, an emergency meeting of the Nobel assembly decided the decision should stand as it "was made in good faith, based on the assumption that the Nobel laureate was alive". In fact, the edict about awards for the deceased was not made until 1974. Before that date, a person could be awarded a prize posthumously if they had already been nominated before February of the same year – as was the case for Dag Hammarskjöld, who won the Nobel peace prize in 1961. Steinman shared his prize with American Bruce Beutler and French biologist Jules Hoffmann. All were honoured for research on the immune system. Prior to his death, Steinman had been treating himself with a therapy based on his own research but died after a four-year battle with pancreatic cancer.

Stem cells may not be the great white hope for medicine in the 21st century after all

The dream that paralysed people could walk again after injections of stem cells suffered a major blow, following the decision by the US biotech giant Geron to abandon the first human trial of its kind. Geron said difficult economic conditions, which make it hard to raise money, had forced it to quit its stem cell work. The decision was a blow to those who thought stem cell therapy for humans would soon become commonplace. Four patients had been injected with Geron's stem cell therapy, the goal being simply to establish whether the treatment was safe. There were no ill effects, but Geron acknowledged that the patients had not seen any improvement, even though lab tests had given paralysed rats the power to move their hind legs. Researchers who are testing stem cells for other conditions, including Alzheimer's and Parkinson's, are still hopeful of ultimate success.

Mars continues to be a tricky place to reach

Despite half a century of sending probes to the red planet, space engineers still have a shaky record of success. Of the 38 Mars missions, 19 have suffered some kind of major flaw, a failure rate of 50%. The latest victim of the Great Galactic Ghoul – as boffins call the curse of Mars probes – was the Russian Phobos-Grunt mission, which was supposed to fly on a 10-month mission to Mars after its launch last month. Instead it found itself stuck in orbit only a few hundred miles above Earth. Despite all attempts to coax the errant satellite to reboot its computers and to relaunch itself towards Mars, its radio emitted only a few, unhelpful beeps before conking out. This leaves planetary scientists pinning their hopes on Curiosity, the giant mobile science laboratory built by the US, which was also launched last month. Set to arrive at Mars in August, six-wheeled Curiosity will be lowered from a rocket-powered "sky crane" on to the planet's surface and will then trundle over it for several years, drilling samples from rocks which it will analyse for signs that the planet once supported life. US space controllers say the craft is currently on a perfect course to Mars. So far, so good.

Archaeopteryx may not have been the world's first bird

This biological bombshell for the science of bird evolution is the handiwork of Xing Xu at Linyi University in China, whose colleagues studied a new Archaeopteryx-like fossil – called Xiaotingia zhengi – and found the creature belonged not in the lineage of birds, but to a group ofdinosaurs called deinonychosaurs. More strikingly, Archaeopteryxappeared in the same group, after their analysis, according to a study published in Nature. Deinonychosaurs, such as the velociraptor, walked on two legs, ate meat and had vicious retractable claws. The finding is tentative, but builds on doubts that have emerged over the special status of Archaeopteryx following the discovery of other bird-like dinosaurs over the past decade or so. Archaeopteryx was discovered in 1861, two years after Charles Darwin published On the Origin of Species. The spectacular fossils of an animal with the feathered wings of a bird, but the teeth and tail of a dinosaur, caused an immediate sensation in Victorian England, where society was wrestling with the consequences of evolution through natural selection. The creature became renowned as the most primitive bird on the planet – until now. Certainly, doubts about its status are rising, though many scientists remain cautious. As Paul Barrett, a dinosaur researcher at the Natural History Museum in London, says: "Maybe Archaeopteryx wasn't on the direct ancestral line to birds, but was part of an early experimentation in how to build a bird."

And finally, we learned that the Higgs boson really does exist

Well it probably does. Or put it this way, it might just possibly be real. On the other hand, it is also possible that it might not exist. After spending a decade and around £6bn building the Large Hadron Collider on the Swiss-France border in order to smash particles together at colossal speeds and so recreate conditions of the early universe, scientists reported this month that the prime goal of these efforts – the pinpointing of the Higgs boson, the entity which gives all other particles their mass – may have been realised. Two experiments on the collider both noted evidence of a particle at a mass of around 125GeV being created from their collisions. This could be the Higgs boson, they declared. On the other hand it might not be, they added. "There is definitely a hint of something around 125GeV but it's not a discovery yet. We need more data! I'm keeping my champagne on ice," said Jeff Forshaw, a physicist at Manchester University. In other words, the collision data might just be a statistical anomaly that could disappear once more results come in. So all we have to do is wait for another 12 months and then we should know – one way or the other. Something to put in next year's science review, if nothing else.