NASA rushes spacesuit repair kit to space station

A spacesuit repair kit has been delivered to the International Space Station, filled with tools and spare parts to hopefully fix astronaut Luca Parmitano's leaky helmet.

Parmitano and fellow astronaut Christopher Cassidy were on a spacewalk on 16 July making repairs outside the station when their task had to be aborted: Parmitano had reported that he felt water on the back of his head. His helmet rapidly filled with liquid, which floated into his eyes, nose and mouth. Cassidy helped him re-enter the ISS and crews quickly removed his helmet and gloves. They later reported that about a litre of water had leaked into the spacesuit.

NASA is still investigating the cause of the leak, although they have narrowed it down to a few possible systems inside the suit. In the meantime, mission managers decided to send up a selection of repair tools on the next available ISS resupply mission, an uncrewed Russian Progress spacecraft that launched from the Baikonur Cosmodrome in Kazakhstan on 27 July.

House in space

"It was a small amount of repair equipment and tools that were sent up that, together, could be used for any of the possible options that could have caused the leak," says NASA spokesperson Josh Byerly at the Johnson Space Center in Houston, Texas. "They launched three tools and a small set of spare parts for the candidate culprits, such as the sublimator, the gas trap, the condensate water valve and the water separator."

These are all parts of the portable life-support system that is mounted to the back of NASA spacesuits used during spacewalks. This system controls levels of oxygen and carbon dioxide in the air the astronaut is breathing, and it removes excess water vapour to control humidity, condensing the vapour into a cool liquid for disposal or recycling.

Although you might expect the space station to be readily stocked with tools to fix broken suits, even astronauts cannot be prepared for every scenario. "It's just like when you are working on your house. Sometimes you have to make a trip to the hardware store," says Byerly. "It just so happens that the store is here on the ground and the house is in space."

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Mummified Inca child sacrifice gives up her secrets

Sitting cross-legged, a Mona Lisa half-smile playing on her lips, the Llullaillaco Maiden looks at peace. When she was unearthed in 1999, the coca quid in her teeth and her icy mountaintop tomb were the only clues that she was part of an Inca child sacrifice ritual 500 years ago.

Now the latest studies of her perfectly preserved body offer an unprecedented glimpse into her life in the months leading up to her death – possibly from hypothermia – and raise questions about the extent to which she was aware of, and accepted, the fate that had been mapped out for her.

The frozen body of the 13-year-old Maiden was entombed in a small chamber 1.5 metres underground near the summit of Volcán Llullaillaco in Argentina, together with the bodies of two 4 or 5-year-olds. With the blood still visible in their hearts and their lungs inflated, the three are probably the best-preserved mummies anywhere in the world, says Andrew Wilson at the University of Bradford in the UK. "They look very recognisable as individuals, which adds to the poignancy of their story."

The children were the centrepiece of an elaborate capacocha ritual – the Inca practice of child sacrifice used to mark important events in the emperor's life. What we know about the ritual comes from 17th-century Spanish accounts, but they reveal little from the children's perspective. The mummies, in particular that of the Maiden, help fill that gap.

Timeline in hair

"She has fantastically tightly braided hair, which effectively acts as a timeline stretching back almost two years before her death," says Wilson. With colleagues, he has analysed how chemical traces in the hair differ from root to tip. The results show the Maiden experienced important dietary changes in those final two years.

Around 12 months before her death, for instance, the Maiden's diet changed markedly from simple to much richer food – perhaps indicating the moment that she was plucked from humble surroundings and elevated to a higher status as someone chosen for sacrifice.

The chemical markers also show she consumed large quantities of alcohol and coca – from which cocaine is extracted – in the final months of her life. Her coca use peaked when she had six months to live, possibly coinciding with a hair-cutting ritual she underwent at the time. The final six weeks of her life, meanwhile, were marked by her consuming more alcohol than usual. This was not seen in the two younger children sacrificed alongside her, who almost certainly both played some subordinate "attendant" role in the capacocha ritual.

This difference intrigued Wilson and his colleagues, who speculate that it may reflect a greater need to sedate the Maiden as the capacocha ritual approached.

Coping mechanism

It's certainly a possibility, says John Verano at Tulane University in New Orleans, Louisiana. "We can only hypothesise, but being older, she might have had more of an idea of what was going on around her," he says. And although she may have considered her imminent death an honour – as we know the Inca were encouraged to do – it may equally have caused her anxiety. "Was she nervous and using drink as a way to deal with it?" asks Verano.

However, Verano points out that the Maiden's increased intake of alcohol may simply reflect her involvement in more rituals before the capacocha – maize beer being an important component of Inca ceremonies.

Charles Stanish at the University of California, Los Angeles, offers another interpretation: rather than the alcohol and drugs being used to sedate the Maiden to make it easier for her carers to manipulate her, they might have been for her benefit – to numb her to her fate. "Some would say that within this cultural context, this was a humane action," he says.

There may be a way to throw more light on the issue, says Verano. Hair also contains the stress hormone cortisol, so it should hold clues to the Maiden's stress levels. "If [cortisol] also increased towards the end of her life, that would certainly be interesting," he says.

Journal reference: PNAS, DOI: 10.1073/pnas.1305117110

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Today on New Scientist

Clouds save Earth from runaway greenhouse hell

The cooling effect of clouds may be what is standing between us and the sweltering conditions seen on Venus

Fixing broken brains: a new understanding of depression

Untreatable depression is on the rise, hinting at fundamental flaws in our understanding of the illness. But new treatments offer hope for everyone

Emmy equals Einstein squared

Discovering symmetry's unsung heroine is all part of a very wild ride through Dave Goldberg's book The Universe in the Rearview Mirror

A garden of my own amid a sea of garbage

In Djenné, Mali, a green-fingered local takes some time to tend his garden in this runner-up photo from the Travel Photographer of the Year 2012 competition

'Parasitism is the most popular lifestyle on Earth'

Parasites are all around us – humans alone have 100 – yet they receive little attention. That should change, says ecologist Kevin Lafferty

Outbreak of global warming optimism is naive

Hopes that we have extra time to rein in emissions and avoid severe climate change are missing the bigger picture, says an energy industry watcher

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Fixing broken brains: a new understanding of depression

Editorial: "New thinking means new hope on depression"

ONE OF Vanessa Price's first chronic cases involved a woman we'll call Paula. Paula came to the London Psychiatry Centre, where Price is a registered nurse, after two years of unrelenting depression. First she stopped seeing her friends. Then she stopped getting out of bed. Finally, she began cutting herself. Sessions with a psychiatrist didn't help, nor did medication. In fact, they made it worse. Paula had joined the ranks of people diagnosed with treatment-resistant depression.

The steady rise in this diagnosis over the past two decades reflects a little-known trend. The effectiveness of some antidepressant drugs has been overstated, so much so that some pharmaceutical companies have stopped researching them altogether.

The stubborn nature of these cases of depression has, however, spurred research into new and sometimes unorthodox treatments. Surprising and impressive results suggest that we have fundamentally misunderstood the ...

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Emmy equals Einstein squared

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• Book information


• The Universe in the Rearview Mirror : How hidden symmetries shape reality by Dave Goldberg


• Published by: Dutton Books


• Price: $27.95

Symmetry is vital to the workings of our world from particles to wheels (Image: Sophie Chivet / Agence VU/Camera Press)

Discovering symmetry's unsung heroine is all part of a very wild ride through Dave Goldberg's book The Universe in the Rearview Mirror

"IF WE'RE trying to understand all that there is, we're going to have to dig a little bit deeper," says astrophysicist Dave Goldberg, laying out his ambition for this book. This ambition is nothing less than to illuminate the basis of modern physics and, arguably, the fulcrum of our knowledge of the world – the idea of symmetry.

Symmetry is more than the aesthetic balance in colonnades and butterfly wings. In the much more general, physics sense, it can apply to time, space, electrical charge, spin, and even more abstruse properties of matter.

Loosely, symmetry means that when you change one thing, other things remain unchanged and still behave the same way. Rotate a square by 90 degrees, and it looks the same. A circle is more symmetrical, because it can be rotated by any angle and look the same. As well as rotation, symmetries include reflection, translation (shifting everything along in one direction) and translation in time (resetting the clocks). As Goldberg explains, symmetry is not just the reason why wheels work, but also why E = mc² , why atoms exist, and why the floor holds you up.

Emmy Noether's theorem may be the most profound idea in science (Image: Science Photo Library)

Symmetry's central position in modern physics stems from a stunning insight by a German mathematician called Emmy Noether. The daughter of Max Noether, a mathematics professor at the University of Erlangen, she chose to stay in the family business despite the resistance to women in the field. Working unpaid for much of her career, Noether surpassed her eminent father when, in 1915, she proved that every symmetry in nature leads to a conserved quantity.

Her work was inspired in part by Einstein's newly published general theory of relativity, an extension of his special theory.

It may sound obscure, but Noether's theorem is possibly the most profound idea in science. It tells us that because physics remains unchanged if you move a bit to the left or right, total momentum in the universe must remain unchanged. Because physics is the same today as it was yesterday, there is a conserved thing called energy. The idea of a link between time and energy is still startling today. And that is only the beginning. After Noether's work, fundamental physics became a search for symmetries.

Unsurprisingly, she was not always well treated by the mathematics establishment. Goldberg tells us how she found an ally in the mathematician David Hilbert, who recalled how "tradition, prejudice, external considerations, weighted the balance against her scientific merits and scientific greatness, by that time denied by no one".

When Noether was first denied a Privatdozent (a title conferring the right to lecture), Hilbert made a rousing but futile defence of her. "I do not see that the sex of the candidate is an argument against her admission," he said. "After all, we are a university, not a bathhouse."

Although Noether is well known among mathematicians today, having established much of the basis of modern algebra, she deserves wider fame. Goldberg is a cheerleader, considering her the star of his story. Even so, I was disappointed by how briefly she appears, and wanted more on how she proved her theorem.

Ancient symmetries

But Goldberg is a restless author and there is much to cover. And so we are off, discovering more of nature's strange and subtle symmetries. We learn how particle replacement symmetry and the quirks of quantum spin combine to nail together the periodic table – and how physicists Chen Ning Yang and Robert Mills extended Noether's work to show that symmetries generate all the particles and forces in the universe.

We also discover that symmetries can break in interesting ways. Broken symmetries today hide the underlying simplicity of unified quantum fields, which would have been evident to a physicist lurking in the very hot early universe. The main object of fundamental physics is to reconstruct these ancient symmetries from our cooler perspective.

One slightly broken symmetry allowed matter to triumph over its evil twin, antimatter, in the early universe. Matter sprang from a hot bath of gamma radiation: our genesis is "much like [that of] The Incredible Hulk," says Goldberg. Clearly it helps to be on top of your comic books and speculative fiction, as Goldberg packs in sci-fi, superheroes and fantasy references.

On the whole, this tendency doesn't warrant the apologies that Goldberg makes, although the allusions sometimes seem forced. He describes, for example, how it is possible to detect neutrinos by "building giant detectors underground – oddly reminiscent of the Dwarrowdelf in Middle Earth".

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A garden of my own amid a sea of garbage

Caption (Image: Timothy Allen)

YOU can grow food in the unlikeliest of places, it seems. Here in Djenné, Mali, a green-fingered local takes some time to look after his garden.

Photographer Timothy Allen took the picture while in Mali to photograph the annual restoration of the Great Mosque of Djenné. "By chance I stumbled across the scene during an evening stroll," he says. "The garden stood out from the very yellowy mudbrick colour of Djenné."

During the dry season the Bani river, seen in the background, shrinks back and exposes the mass of litter and debris thrown away by Djenné's 33,000 inhabitants. While the town's population normally uses mud from the river banks as a building material, this farmer took advantage of the damp riverbed and nearby water supply to grow some crops. "The area he was working in would be underwater during the rainy season," says Allen.

Many farmers have been displaced by conflict in the north of Mali and the United Nations has emphasised that they must be helped to return to their lands – though this farmer's story is unknown. Allen suggests he could be growing herbs or cassava for himself and his family.

The image won Allen a runner-up prize in the Travel Photographer of the Year 2012 competition. A selection of the photos is now on display at the Royal Geographical Society in London.

This article appeared in print under the headline "Island of green"

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'Parasitism is the most popular lifestyle on Earth'

Parasites are all around us – humans alone have 100 – yet they receive little attention. That should change, says ecologist Kevin Lafferty

Why did you choose to focus your work on parasites, the least loved of creatures?

I wasn't interested in parasites until I was asked to be a teacher's assistant for a parasitology course. I hadn't taken the course; I was totally disgusted by the subject. But I became fascinated when we brought in fish, sharks and invertebrates for the students to dissect. As a marine biologist, I thought I knew pretty much everything about these organisms. Yet no one ever told me to look inside them for parasites. When we did, we found lots of species. It struck me that an entire component of my education had been neglected. At that point I decided that there's a real need to know more about the role of parasites.

How significant are parasites in nature?

We don't know for sure, but we do know that parasitism is the most popular lifestyle on Earth. Most animal species are probably parasitic. For humans alone, there are more than 100 host-specific parasites. Among described species on the planet, the ratio of free-living to parasitic is about 60:40, but that's a gross underestimate. In reality, the numbers are probably much more in favour of the parasites.

If they are so prevalent, why don't they get more attention?

Almost all intellectual effort focused on parasites is directed at how we can kill and prevent them. That's not the best way to get an insight into their ecological role. Early ecologists were well aware of parasites, but in more modern times that aspect of thinking was dropped. There has been little training to look inside organisms. Fortunately that has changed in the last 10 years and we have seen an incredible surge of interest.

How important are parasites to ecosystems?

Parasites are integral, basic components. The more intact the ecosystem, the more parasites you tend to find there. That can be shocking to people, who usually think parasites are a sign that a system is out of balance. In general, though, we tend to find lots of parasites in pristine places.

But I don't want to sound romantic about parasites and tell you they are great – I mean, they are our enemies. Anybody with parasites doesn't harbour any warm feelings towards them.

How will climate change affect parasites?

For free-living species, what we expect to see with climate change is that there will be some winners and some losers. Parasites, for the most part, are going to follow similar patterns. They will shift ranges, and those that can't will be reduced as a consequence. For example, the whole map of malaria risk in Africa is likely to change, but not necessarily become worse. That's a pretty controversial statement to make because there has been an awful lot written about how climate change is going to lead to a sicker world.

Have you been host to any interesting ones?

My first experience with a parasite was at summer camp when I had a tick on my testicle. It was emotionally scarring. All the kids looked on as a camp counsellor burned the tick off with a match.

This article appeared in print under the headline "One minute with... Kevin Lafferty"

Profile

Kevin Lafferty is a research ecologist who specialises in parasite and conservation biology at the University of California, Santa Barbara, and the US Geological Survey

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Outbreak of global warming optimism is naive

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Hopes that we have extra time to rein in emissions and avoid severe climate change are missing the bigger picture, says an energy industry watcher

Editorial: "We can't afford to wait on climate change"

DOOM-MONGERS of the climate variety might want to look away now – we apparently have more time to save the planet. A recent study published in Nature Geoscience suggests it will warm more slowly than feared, perhaps buying an extra decade for action.

There are other reasons to be cheerful. The International Energy Agency (IEA) has just said nations can get back on track to keep warming below 2 °C at no net economic cost. President Obama is talking tough on emissions and the US and China, the biggest emitters of greenhouse gases, are, incredibly, collaborating on efforts to curb them.

So it all adds up to an unexpected opportunity to get ahead of the crisis – or at least catch up. Or does it?

The idea that preventing the worst of global warming might be not only sensible but also economically sound is not new: in 2007 the UK's Stern review concluded it would cost just 1 per cent of global GDP. Of the recent developments, what is really surprising is the IEA's suggestion that keeping the hope of 2 °C alive until 2020, when a new global treaty could come into force, can be achieved effectively for free.

Even more surprising, the IEA's plan to achieve this rests on just four policies: improved energy efficiency; limiting use of the most inefficient coal-fired power stations; reducing methane leaks from oil and gas production; and phasing out fossil fuel subsidies. It says these could deliver 80 per cent of the reductions needed by 2020. Unfortunately it all looks like pie in the sky.

The biggest questionable assumption is the reliance on efficiency to deliver half of the projected emissions reductions. Of course, like motherhood or world peace, efficiency is hard to knock. But history suggests that in a straight fight with economic growth, it usually loses and emissions continue to rise.

There are exceptions. The latest BP Statistical Review of World Energy points out that energy consumption in the industrialised world has fallen in four out of the last five years, and that in three of those four the economy grew. Last year, for example, energy consumption in the OECD countries, mainly advanced economies, fell 1.2 per cent while the economy grew 1.4 per cent. Apparently it is possible to loosen the ties between growth and energy consumption, but perhaps only when growth is feeble.

Unfortunately it is not true where it really matters. Since 2008, when the West plunged into recession, energy consumption in the OECD has been increasingly overtaken by the non-OECD nations, such as China, India and Brazil. They now claim 56 per cent of global energy. Great strides have been made in improving efficiency too, but these have been overwhelmed by growth. China has roughly halved its emissions per unit of economic output over the past 20 years, yet despite this its energy consumption and emissions have more than doubled as the economy boomed over the past decade.

In 2012 alone, the IEA notes approvingly, China's energy efficiency improved 3.8 per cent – yet still its emissions rose by 300 megatonnes, contributing three-quarters of the entire global increase. In other words, global carbon dioxide emissions have climbed inexorably to record highs, and an atmospheric concentration of 400 parts per million, in spite of significant efficiency gains by the world's biggest emitter and the OECD.

There seems little reason to expect these trends will change in the coming decade. China's economy has proved resilient in the face of widespread slowdown, and per capita GDP and energy consumption are still a fraction of those in the West. A senior Chinese official said last year the country's emissions would grow until per capita GDP had risen fivefold. In this context, it is hard to imagine the IEA's efficiency measures – sensible as they are – making much of a dent.

Some of its other proposals – phasing out fossil fuel subsidies in the Middle East, for example, where dirt cheap petrol and electricity are vital to defending the thrones of local tyrants – look equally forlorn.

If the IEA's plan looks unlikely to keep a 2 °C trajectory alive until 2020, it is not even clear that this is the right target, or that we have any "extra" time as has been suggested. On the contrary, many climate scientists, including James Hansen and Pushker Kharecha, argue that 2 °C of warming would trigger catastrophic consequences, and the increase must be limited to 1 °C.

This would mean leaving most known fossil fuel reserves alone, never mind the emerging unconventional resources such as shale oil and gas, the amount of which in the US was recently estimated by the country's Department of Energy to be equivalent to 10 years of global demand. Given that we have already started exploiting non-conventional oil and gas sources, it would imply immediate and continuing cuts in fossil fuel consumption.

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A phone, or an all-seeing sentry at your command?

Video: Stick-on lens gives your phone peripheral vision

PUT your smartphone down on a table and it will necessarily ignore you. But give it peripheral vision and it could interact with you and your surroundings like never before.

Phones can already record wrap-around imagery using omnidirectional lenses like the $49 Dot lens made by start-up firm Kogeto, based in New York City. Fixed to a smartphone's main camera, it lets you shoot immersive, 360-degree photos and video. On playback, you can pan around within the footage, or watch all 360 degrees at once. But until now, a Dot-equipped phone could not recognise or respond to anything in its environment.

It can now. Xing-Dong Yang at the University of Alberta in Edmonton and colleagues reasoned that, if placed on a phone's user-facing camera instead of the main, rear one – which mostly points at the ground – such a set-up could monitor activity and track objects in the user's surroundings. So the team fitted a Dot to the front camera on an HTC Butterfly phone and trained an Android app to recognise locations and gestures.

Users can use the app to control laptops, wireless speakers and other objects with pinch and swipe gestures in the air. The app can also ask the user if they have forgotten their phone when they walk away from it. If you don't want your phone, a sweeping hand gesture sets it to voicemail mode. Recognising multiple faces present in a gathering, the phone automatically mutes itself, and if it identifies the interior of your car and hears engine sounds, it blocks calls as a safety measure, Yang told New Scientist.

Called Surround-See, Yang's combination of lens and app gives just a glimpse of what smartphones could offer if fitted with depth-sensing cameras. That became a distinct possibility last week after it emerged that Apple is in talks to purchase PrimeSense, the Israel-based firm that pioneered the depth camera at the heart of Microsoft's Kinect sensor. The news is fuelling speculation that future Apple devices will be fitted with gesture-sensing technology.

"Surround-See is a nifty idea," says Chris Harrison of Carnegie Mellon University in Pittsburgh, Pennsylvania. "For smart devices to get smarter, they need more information, so having a sensor like this brings new capability."

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Astrophile: The changing face of icy dirt-ball Quaoar

Astrophile is our weekly column on curious cosmic objects, from the solar system to the far reaches of the multiverse

Object: Quaoar, a Kuiper belt misfit

Shape: Craggy, or eggy

Pluto shouldn't complain. It may no longer be a planet, but at least it gets to be the beloved king of the dwarfs. Life isn't so simple for Quaoar, another ball of ice and rock adrift in the freezing fringes of the solar system.

It was once Pluto's second in command, the second-largest object in the Kuiper belt, a ring of dwarf planets and other bodies beyond the orbit of Neptune. But new, bigger worlds kept turning up. Meanwhile, the size of Quaoar (pronounced "kwawar") was revised downwards thanks to improved measurements. The strange world was all but forgotten.

Now Quaoar may have lost its last remaining honour, as the densest object in the Kuiper belt. The latest revisions to its size, density and shape suggest that the neglected object has a lot more in common with its neighbours than we suspected.

That could be a good thing – its new, larger size potentially ups its eligibility for membership to the dwarf planet club, which was formed as a result of Pluto's fall from grace. Except that Quaoar seems to be an ellipsoid, which could be a no-no – even dwarf planets must be spherical.

Screwy mountains

Named for a Native American creator-god, Quaoar orbits at about 6.5 billion kilometres from the sun. Its size puts it near the limit of what the Hubble Space Telescope can see, making it hard to tease out details. Previous work combed over Hubble's blurry images and made models of Quaoar and its only moon, Weywot, based on the notion that both objects would look roughly like the moons of Uranus. That research hinted that Quaoar is about 900 kilometres wide and so dense that it may be mostly rock – unusual for the Kuiper belt, where most objects are mixtures of ice and dirt.

But infrared views from modern telescopes, such as the Herschel space telescope, and other observations showed that Quaoar's surface composition is nothing like anything seen on the Uranian moons. So Felipe Braga-Ribas of the National Observatory in Rio de Janeiro, Brazil, and colleagues took a different tack.

In 2011 and 2012, multiple teams watched Quaoar cross in front of a star, making that star wink out for a short while. By carefully timing the observations and recording the changes in starlight, these occultations gave some of the most accurate measurements yet of distant Quaoar's size and shape.

Eggy Quaoar

Braga-Ribas's team calculates that Quaoar is actually 1138 kilometres wide – a bit bigger than the dwarf plant Ceres – and that it has a density of just 1.99 grams per cubic centimetre, which would make it more of an icy dirt-ball like Pluto.

But there's a catch. The occultations make most sense if Quaoar is an elongated ellipsoid incorporating either a very large mountain or a deep crater. The trouble is that neither feature should last for long if the object is made of an ice-rock mixture. "When you take the times recorded at face value, Quaoar looks screwy – it's completely unreasonable," says Wesley Fraser of the Herzberg Institute of Astrophysics in Victoria, British Columbia, Canada, who was not on the research team.

So the team also examined what it would take for a smoother shape to fit the data. Assuming slight timing errors that are mostly within expected limits, a featureless but rounder, egg-shaped ellipsoid could fit too.

Kuiper chemistry

Braga-Ribas's team also reports no atmosphere on Quaoar. This is something that Fraser finds suspicious. "Most of the large objects in the Kuiper belt are expected to have atmospheres of some sort," he says. "They have moderately volatile ices on their surfaces that are relatively warm; enough to produce slight, tenuous atmospheres."

In work submitted to the Astrophysical Journal Letters, Fraser and his colleagues present data from when Quaoar seemed to pass the edge of a star in mid-July, from the perspective of the Gemini South telescope in Chile. They rule out a nitrogen or carbon monoxide atmosphere, but they think a pure methane atmosphere is still possible, and that a fluffy, diffuse covering of methane would actually fit with Braga-Ribas's occultation results. Either Quaoar does have a slim envelope of gas, or it is somehow defying our understanding of Kuiper belt chemistry.

What is clear from the various sightings is that Quaoar is not perfectly round. But when the International Astronomical Union (IAU) redefined planets, it also decided that dwarf planets need to be massive enough that their gravity makes them at least nearly round. So does Quaoar's probable egg-shape exclude it from the club?

"Ceres isn't perfectly round either. That would suggest the IAU definition may need to be re-examined," says Fraser. "I would lean towards calling it a dwarf, and someone would have to convince me otherwise."

Journal reference: Astrophysical Journal, DOI: 10.1088/0004-637x/773/1/26

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