CDC panel gives thumbs up to vaccine against nine HPV types

Gardasil 9, a vaccine that offers protection against nine types of HPV, has been recommended for use in 11- and 12-year-old girls and boys and in females ages 13 to 26 and males ages 13 to 21 who have not previously been vaccinated or treated with the three-dose series.

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A federal vaccine advisory committee voted February 26 to recommend use of an expanded version of the human papillomavirus shot marketed as Gardasil.

The move, by the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices, clears the way for the broader-coverage vaccine, called Gardasil 9, to be used in the clinic. Current vaccines offer protection against four types of HPV, which causes cervical cancer and is linked to other cancers. The new shot expands protection to nine types of HPV.

While the Food and Drug Administration’s licensure of Gardasil 9 was granted in December, doctors need CDC guidance on any new vaccine’s dosage and scheduling of shots before putting it into use. The new recommendations add Gardasil 9 to shots routinely scheduled for girls and boys age 11-12, but can be given as early as age 9. Gardasil 9 is also recommended for females age 13-26 and for males ages 13 to 21 who have not completed a three-shot series of an HPV vaccine.

Do Russia's flying Bears really pose a risk to civilian air traffic?

Move along now. Ministry of Defence, CC BY

There’s an element of sabre-rattling to Russia’s Tu-95 “Bear” aircraft probing the boundary of European nations' airspace, something that had long gone on during the Cold War and which has restarted under Vladimir Putin. But while their probing of air defences and the subsequent response is well-rehearsed, aircraft flying stealthy around some of the world’s busiest airspace holds the potential for disaster.

The large, propeller-driven Tupolev Tu-95 aircraft were introduced in the 1950s as long-range strategic nuclear bombers, but most of the remaining Bears are reconfigured for either maritime reconnaissance or for gathering electronic intelligence (Elint) – almost certainly what the Bears intercepted by RAF Typhoons off Cornwall were doing.

The flights' aim is to inspect as much of the electromagnetic emission spectrum around UK airspace as possible. This includes emissions from air defence surveillance radars, fighter aircraft radars and command and control communications. The information gathered is used to update Russian electronic warfare systems. In times of war or conflict this information would be used to program electronic jamming systems on-board Russian aircraft in an attempt to interrupt UK air defence radar and communications. The same techniques are used in relation to warships and for land operations.

This electronic eavesdropping activity is not confined to the borders of UK airspace – within the last year, fighter aircraft have intercepted Tu-95s around Turkey, Portugal, Germany, Denmark, Finland and Sweden and, in late 2014, a major Russian reconnaissance exercise was conducted off the US west coast. The Russian Air Force reconnaissance programme is particularly active during NATO exercises as the electromagnetic spectrum is rich with military information.

Invisible to civilian aircraft

To ensure safety in designated air corridors, commercial and civilian aircraft employ what is called secondary surveillance radar (SSR) to identify themselves to air traffic control (ATC). This is a transponder that periodically transmits location, bearing, altitude and other information to ATC. Military aircraft employ similar but more secure systems known as Identification Friend or Foe (IFF). In peacetime or when military aircraft fly in designated air corridors, IFF is operated in a civilian-compatible mode for safety in order to remain “visible” to air traffic controllers.

Russia’s Bears, on the other hand, turn off their IFF transponders so as to maintain the element of surprise. This prompts British air defences, using active radar to sweep the skies, to detect and respond to them as an unknown potential threat. It also means they are invisible to civilian air traffic control and invisible to other aircraft in the sky – unless close enough to be seen by pilots and crew themselves.

While the aircraft design may be more than 50 years old, the Bears are fitted with sophisticated reconnaissance and navigation systems that enable them to adhere to air safety standards by avoiding controlled airspace and busy air corridors. Nevertheless there have been reports of near misses and violations of sovereign airspace, but it’s difficult to separate fact from fiction.

New Cold War? Ministry of Defence, CC BY

Near misses

For example, in December 2014 there was a close encounter between a passenger flight taking off from Copenhagen carrying 132 passengers bound for Rome and a Russian reconnaissance aircraft, with transponders turned off, 50 miles south-east of Malmo. A collision was apparently avoided thanks only to good visibility and the alertness of the airliner’s pilots.

Another came in April 2014 when a Russian reconnaissance aircraft entered Dutch airspace before being intercepted by Dutch fighter aircraft. Again, the objective was Elint collection on NATO air defence systems.

Although there have been reported near misses the actual risk to commercial air traffic is considered minimal – but vigilance is necessary. NATO air defence systems are well integrated into civilian air traffic control systems so once an intruding Bear has been identified controllers can be alerted to the presence and aircraft in the vicinity can be warned.

Not just the Russians

However this is not an activity reserved for the Russians. NATO, and particularly the UK and US, also undertake extensive reconnaissance Elint operations against Russia and other countries deemed hostile.

Throughout the Cold War, extensive operations were undertaken against the Soviet Union in areas stretching from the Scandinavian Kola Peninsula, through the Baltic and Germany to the Black Sea, with similar operations in the Far East. This continues today, with incidents in which NATO surveillance aircraft tracked by Russian defences. The Israeli Air Force proved that Elint and electronic warfare was vital during the Lebanon War in 1982 against Russian-built air defence systems supplied to Syria.

But it has not been without casualties – early in the Cold War several NATO reconnaissance Elint aircraft were shot down by the Soviets around the Baltic and Black seas, so these missions were sometimes considered dangerous. Today the Royal Air Force and the USAF employ Boeing RC-135 Rivet Joint reconnaissance aircraft to fulfil the same role for NATO as the Tu-95 Bear, and operate in a similar manner. Perhaps such surveillance, although concerning to some, actually benefits both sides: by keeping the military on their toes and discovering more about each other’s military capabilities, it makes the prospect of war less likely.

Can a zen-like state of mind power super cyclist to one of sport's great world records?

Sarah Storey in the zone David Davies/PA

A golden age of British cycling appears to be coming to an end. In the recent World Championships in Paris, the country’s cyclists performed below expectations, recording their poorest showing at that level since 2001.

Yet the World Championships don’t include the event that many purists regard to be the most demanding challenge in the sport: the one-hour time trial. The current women’s world record stands at 46.065km, set by Dutch rider Leontien Zijlaard-Van Moorsel in Mexico City in 2003. The men’s record under the current rules was set several weeks ago in Granges, Switzerland, by Australia’s Rohan Dennis, who achieved 52.491km.

On February 28 at the Lee Valley Velodrome in London, Dame Sarah Storey will aim to break the women’s mark. Only a handful of British riders – and none from the current generation – have held these records.

It is worth noting – but not central to the narrative – that Sarah Storey is a paralympic champion. Born without a functioning left hand, she is a 20-times world champion in swimming and cycling. She has been at six Olympics and has competed both against disabled and able-bodied athletes at the highest level. But more than any other challenge perhaps, the one-hour time trial is her opportunity to establish a position in the history of the sport.

In sport, preparation is everything. The venue will be warmed to around 25 degrees to ensure the minimum of air resistance. The sport-science team behind Storey will have data to ensure the optimal gearing and weight of the bike. In the only concession to Storey’s paralympian status, one side of her handlebars will be slightly shortened to accommodate her left limb.

The bike and her riding position will have been tested in a wind tunnel to identify the optimal position for reducing drag, thereby translating muscle power into velocity. And over the past months, data will have been collected on physiological parameters leading to the wattage required to go one metre beyond the record, such as blood lactate accumulation.

Mind v matter

Storey and her team will know that every 250m lap must be covered in an average time of around 19.3 seconds to give her a chance. But no rider, Storey included, is a pedal-pounding android. The factor which will ultimately determine whether she achieves her goal will be her 60-minute battle with fatigue, a battle in her mind.

In sports science, there is currently a debate about the extent to which fatigue is about mind over matter. Traditional theories argue that fatigue is a physiological state, independent of the central nervous system, and cannot be consciously overridden.

Fatigue: all in the mind? Lukiyanova Natalia / frenta

This is being challenged by what is called the “central governor hypothesis”. It argues that the brain reaches an emotional decision that it is fatigued based on information from the body.

One of the main consequences of this debate is that the role of psychology in discussions about fatigue has been rehabilitated. Certainly the newer theory sounds intuitively right: anyone who has played sport will appreciate that fatigue is qualitatively different when you are winning as opposed to when you are losing.

What psychology can do

From a psychological perspective, Storey will need to effectively balance the paradox of keeping the brain comfortable while the body suffers increasing discomfort. As the hour progresses, the brain’s signals of fatigue will become more overt and require conscious action to manipulate the central nervous system to keep the record attempt on track.

The margins in this event are so fine that psychologically the rider must be engaged from the first second to the last. Storey has acknowledged that there will be “grippy” points – meaning that the little voice in her head will be intruding and presenting her with things that don’t help.

Primarily these will be about how comfortable she feels. As the hour clicks by, the answer will progressively become “not very”. For a physically well prepared performer, it is likely that they will feel “comfortable” for maybe the first five minutes of the event at most.

One of the most effective strategies for managing a large and difficult task is to chunk it down into manageable sections, with goals for each. The team will be giving feedback on where she is in relation to these.

This feedback is both vital in itself and will also serve to fuel her internal dialogue and the “what ifs” involved – “I’m ahead of schedule, what if I’m going too fast and will exhaust myself before the hour?”; “I’m behind schedule, what if I can’t recover the required tempo?”; or even “I’m bang-on but I’m going at my limit and I’ve still got 40 minutes to go – what if I can’t sustain this?”

She may dissociate from the discomfort through carefully monitoring her thinking, filtering out the unhelpful and reconnecting with positive cues. She may engage in an internal conversation with her legs, as Jens Voigt (a previous holder of the men’s hour record) famously did. He coined the phrase “shut up legs”, which is known to all top riders.

The pain barrier

Ultimately, Storey is searching for a method of coping with profound and potentially overwhelming pain. We know that the body produces its own natural painkillers – endorphins. Recent studies have shown that painkilling drugs do allow riders to ride harder, reporting improved lactate tolerance and maximum safe heart rate.

Yet the solution ought to be natural. The ideal for Storey would be reaching the “zone”, a “zen-like” state in which performers report altered perceptions of effort and pain tolerance.

The search for this state has its roots in some of the earliest research in modern sport psychology. Work as far back as 1977 linked peak performance to “loss of fear” and “ability to execute basic skills”, together with “no thought about the activity being undertaken” and “total immersion in the activity”.

These findings and later research on the concept of “flow” offer some ideas about how riders like Storey should approach the mental side. Flow is about total absorption and engagement in an activity, to the point where normal perceptions of effort and time become distorted. This is often linked to the production of endorphins.

The problem for time-triallists such as Storey is that this so-called “runner’s high” appears spontaneous. Yet some recent work using advanced brain-scanning techniques gives some clues to what a rider can do to capture and harness it.

Storey in Mexico in April 2014 Christian Palma/PA

It suggests for example that Storey should avoid higher-level cognitive thoughts such as calculating lap times or pacing. Better to mindfully focus on attention and awareness cues, such as engaging with the sprinters' line on the velodrome track, the feeling of her feet on the pedal and every face in the crowd. And she should relax, as much as one can when your heart is going at around 190bpm and you are moving at just over 28 miles per hour.

There will be a moment, at around three-quarters distance, where Storey’s emotion will change. This could be in a positive way, where she will know that the record is hers, which will re-engage her and lift her emotionally. Or it could be negative, knowing that it is highly unlikely. At this point she may just get off her bike. The interesting thing to the sport scientist is that physiologically, these two completely different outcomes are identical. What better way to illustrate the vital part that the mind plays in this kind of challenge.

GM regulation 'not fit for purpose', says Commons committee – and it's right

Vitamin A-enhanced GM Golden Rice has become a flashpoint for campaigners despite its health benefits. IRRI

As a scientist who has spent the past 32 years using genetic modification to improve crops and make biological discoveries, the report published by the House of Commons Science & Technology Committee on GM technology is a joy to read. Others, particularly campaigners against the technology, will be dismayed at their failure to convince ten independent-minded MPs of their concerns.

The report is a carefully written assessment of the arguments for and against a controversial method, with many sensible recommendations for what should happen next. It’s a good read for anybody with an interest in new technologies to improve crops, or in how public misunderstanding (often encouraged by campaigners) can result in disproportionate regulation that can hamper innovation.

Reviewing regulations

The report starts by remarking on the scale of the food security challenge, notes that GM has already been widely adopted and points to published findings regarding its safety. The question is whether UK and EU regulations regarding GM food are fit for purpose – and what changes, if any, are required.

Crucially, the MPs endorsed the view that it is wrong to think of GM as a single, generic technology – as the government’s chief scientific adviser Sir Mark Wolpert said:

Whether GM technology is a good or bad thing is not a sensible question; it depends on how it is applied. The question in every case is: what gene, what organism and for what purpose?

The report quite rightly strongly recommends that the government re-frames the debate away from an overly simple notion of “GM”.

Land area in 2011 used for GM crops was 160m hectares, or 1.6m sq km. Fafner, CC BY-SA

Reasoning with the opposition

Those opposed to GM tend to claim it is represented as a “silver bullet” that could alone provide food security, or that it is a technology that could lock its users into a method that “cannot peacefully co-exist with other methods”, or is one that has “squeezed out” other approaches to agricultural innovation. After careful examination of the evidence, the committee found none of these criticisms to be valid.

Paul Burrows, the executive director of BBSRC, told the committee that, of BBSRC’s nearly £500m annual research budget (including £70m spent on plant science), only £4m is allocated to GM research. By this measure GM, far from displacing other research, accounts for only a tiny fraction of it.

The report highlights more complex concerns over intellectual property rights. Industry representatives argued that the long regulatory process and large costs involved in the EU meant that without a competition-free period (through patents) to exploit the inventions, nobody would invest. Such investment is indispensable if we want to meet the food security challenge. On the other hand, the absolute position of campaign group GM Freeze is that “genetic resources are a public good and should not be owned by anybody”. The report is right to recommend that this issue should be examined in depth after the election.

Sidestepping the ‘precautionary principle’

European regulation and the “precautionary principle” (which can be paraphrased as “look before you leap”) have had a major influence on the import and cultivation of GM crops. The committee urges the European Commission to “clearly and publicly state when it has drawn on the precautionary principle in the policy formation process” since there is lack of clarity on this issue. The report is right to “remind the commission that any legislation guided by the precautionary principle must allow for an exit from precautionary measures once there is strong scientific consensus that any risks are low”.

There have been many studies of GM crops in the past. Chris Young/PA

Not fit for purpose

Among the evidence cited in the report is that from Eric Poudelet, the safety director of the European Commission, about the influence of politics on whether or not the European Commission and the Council of Ministers decide to act on the recommendations of the European Food Standards Agency. “Dysfunctional” EU regulation has led to abandonment by major companies of GM-based crop improvement in Europe. Professor Joyce Tait of the University of Edinburgh pointed out that “the more onerous the regulatory system, the more difficult it is for small companies to get through to the market”. This only reinforces the tendency towards domination of the sector by a few large companies.

A crucial finding of the committee is that:

A regulatory system under which it takes many years – sometimes decades – to reach a decision cannot possibly be considered fit for purpose.

The recommendations include several very important points. For example, those campaigning against the technology, such as Greenpeace against pro-Vitamin A-enhanced Golden Rice, should “review their public communication materials to ensure that they are evidence-based and honest in setting out the reasons for opposition to this technology".

The Committee considered alleged health and other concerns about GM crops and concluded that:

The current EU legislative framework for novel plants is founded on the premise that genetically modified plants pose inherently greater risk than their conventional counterparts. The weight of peer-reviewed scientific evidence, collected over many years, has shown this to be unjustified. Where genetically modified crops have been shown to pose a risk, this has invariably been a result of the trait displayed – for example, herbicide tolerance – rather than the technology itself.

We are disappointed that the government has not more publicly argued this fact. We recommend that the government publicly acknowledge that genetically modified crops pose no greater inherent risk than their conventional counterparts.

Bravery in controversy

In summary, ten MPs from three parties currently seeking re-election have written a brave report on a controversial technology. Their recommendations are indisputable. There is nothing intrinsically risky about GM. Current regulation is not fit for purpose; we should regulate specific traits, not the method by which they are delivered, in each member state.

As they themselves conclude: “Regulatory reform is no longer merely an option, it is a necessity.” The report recommends the government makes a commitment to argue for major reform of EU regulation of genetically enhanced novel crops. Legislators must grasp this nettle and remove the regulations that prevent science and technology from improving our crops and providing solutions to longstanding crop problems of weeds, pests and disease.

Baby sea turtles starved of oxygen by beach microbes

Gasp. Magnus Manske, CC BY

On a small stretch of beach at Ostional in Costa Rica, hundreds of thousands of sea turtles nest simultaneously in events known as arribadas. Because there are so many eggs in the sand, nesting females frequently dig up previously laid nests, leaving the beach littered with broken eggs. But these endangered sea turtles are facing a new threat: sand microbes encouraged by the decomposing eggs.

Results from a new study we’ve published in PLOS ONE show how these sand microbes cause low levels of oxygen in the nests that interfere with the embryonic development of the sea turtles.

Despite the large number of nesting females, hatching success at Ostional beach is particularly low. Scientists have long thought that the problem is due to high microbial activity in the sand caused by the decomposing eggs. In a previous study, we found that nests at Ostional have lower oxygen levels than other sea turtle nests do. This suggested that microbial activity did indeed impact nest oxygen – but it wasn’t until now that this was tested and confirmed. It means that we can now use the results to aid the conservation of these endangered turtle species.

Head in the sand

To understand how microbes affect sea turtle nests, we used different treatments to alter the number of microbes within the nest sand. We monitored nest temperature and oxygen levels throughout the incubation period. We also quantified the number of microbes in the sand and the microbial decomposition of organic matter.

Our results allowed us to look at how all of these factors were associated with sea turtle hatching success. We found that removing and replacing the sand, much like the agricultural practice of tilling, was the most successful treatment for increasing hatching success and decreasing microbial numbers. As we suspected, higher numbers of microbes in the sand were associated with lower hatching success as well as lower oxygen and higher temperatures in the nest.

Essentially, microbial activity in the sand at Ostional beach is so high that microbes are taking up all of the oxygen that the sea turtle embryos need to develop. Additionally, just like a compost pile, the microbial decomposition also increases nest temperatures.

Is it safe to come out yet? Author provided

Hatching success of sea turtles is a primary conservation concern, given the current threatened and endangered status of these species. In addition to the disruption of nest oxygen levels by microbial activity, human activity above ground also affects hatching success.

Conservation implications

Increasing temperatures due to climate change could increase microbial decomposition rates even more, further impacting sea turtle hatching success. Temperature increase is a particularly important factor because it determines the sex of the sea turtle and high temperatures are also lethal to embryos. Another human impact on sea turtle hatching success comes from the use of fertilisers and beach re-nourishment programmes, which introduce extra organic materials to the beach. These could fuel higher microbial activity, thus also impacting sea turtle hatching success.

While arribadas occur at very few beaches, sea turtle conservation programmes around the world use hatcheries to protect nests from threats such as beach erosion and poaching. These enclosures into which nests are relocated often have problems with microbial infestations, just like those studied in Costa Rica. Our results will therefore help these conservation programmes by providing sand treatment options to manage microbial infestations and increase hatching success.

Behaviour study shows rats know how to repay kindness

"Remember, we're all in this together." Kuttelvaserova Stuchelova/Shutterstock

Embargoed until 12.00am Wednesday Feb 25

If I scratch your back and you scratch mine, then we’re both better off as a result – so goes the principle of reciprocity, one of the most popular explanations for how co-operative behaviour has evolved. But what if one partner provides a better service than another? A paper by Dolivo and Taborsky shows that Norway rats will only give as good as they get.

As humans, we are familiar with the concept of helping those who help us, whether it is by buying rounds of drinks or expelling diplomats. But demonstrating reciprocity in other species has proved more challenging. Part of the reason for this may be that reciprocity is rarer than might be imagined. But a major factor is the difficulty of establishing an objective means of measuring the costs and benefits of apparently helpful behaviour in the field.

Do as you would have done to you

This is where the laboratory rat comes in. If the economics of behaviour elude field measurement, an attractive alternative is to perform controlled lab experiments. Dolivo and Taborsky trained rats to pull on a stick that drew a food item within reach of a rat in an adjoining cage separated from them by wire mesh.

They then introduced a further treatment in which an experimental rat was placed in a cage with other caged rats on either side. On one side the rat pulled a stick that provided pieces of carrot to the rat in the central cage, while the other pulled a stick that produced banana pieces. In subsequent trials the focal rat had the opportunity to repay the other rats using the same stick apparatus to deliver food items.

Now, the rats had typically turned their noses up at the carrot and showed a strong preference for the more desirable banana. On the basis that the banana-providing rat should therefore be remembered as the superior partner, the authors predicted that in the test phase the focal rat would more readily help provide for banana-purveying rats than for carrot-offering rats. This proved to be the case, so it did seem that the rats that had provided better help in the past received greater rewards, as expected if they were behaving reciprocally.

Behavioural scientists have questioned the extent to which non-human animals have the capacity to engage in reciprocity without being exploited by “cheats” who take advantage of their kindness. It seems that this is cognitively demanding, in terms of bringing together the memories of who did what and judging how to respond.

Dolivo and Taborsky’s latest results show that rats can recall the quality of help provided and by which rat, and adjust their subsequent behaviour so as to invest more time and energy in helping those that helped them. Taken together with the Taborsky group’s prior findings that rats are more likely to help a partner that had helped them before than one that had not helped them at all, these results provide interesting insight into how animals are able to manage the challenges of conditional co-operation.

Not just rats

It is increasingly apparent that we shouldn’t underestimate the ability of animals to engage in reciprocity. For example, a 2006 study by Alicia Melis and colleagues reported that chimpanzees took into account their experience with potential partners when choosing which to recruit for a collaborative venture.

A similar effect is seen among client fish – those species that are co-operatively served by other species of cleaner fish – which will preferentially associate with cleaner fish they have observed behaving in a co-operative manner. So there is evidence that other animals can assess the quality of partners and behave conditionally – a requirement for reciprocity to work.

The latest paper fits within a resurgence of interest in reciprocity, as researchers take up the challenge laid down by critiques questioning its occurrence in non-human animals. For example, the classic case of blood donation among vampire bats has been revisited with a demonstration that the best predictor of donations received was whether donations had been made.

Meanwhile recent experiments with pied flycatchers also appear to demonstrate that birds will help those that have helped them mob owls in their territories.

Good examples of reciprocity in non-human animals may be uncommon but Dolivo and Taborsky’s work supports the view that, where reciprocity does pay, animals can make it work through co-operating conditionally and favouring those partners which provide the best quality help.

Earth's other 'moon' and its crazy orbit could reveal mysteries of the solar system

Cruithne's wacky orbit around the sun YouTube, CC BY-SA

We all know and love the moon. We’re so assured that we only have one that we don’t even give it a specific name. It is the second-brightest object in the night sky, and amateur astronomers take great delight in mapping its craters and seas. To date, it is the only other heavenly body with human footprints.

What you might not know is that the moon is not the Earth’s only natural satellite. As recently as 1997, we discovered that another body, 3753 Cruithne, is what’s called a quasi-orbital satellite of Earth. This simply means that Cruithne doesn’t loop around the Earth in a nice ellipse in the same way as the moon, or indeed the artificial satellites we loft into orbit. Instead, Cruithne scuttles around the inner solar system in what’s called a “horseshoe” orbit.

Cruithne’s orbit

To help understand why it’s called a horseshoe orbit, let’s imagine we’re looking down at the solar system, rotating at the same rate as the Earth goes round the sun. From our viewpoint, the Earth looks stationary. A body on a simple horseshoe orbit around the Earth moves toward it, then turns round and moves away. Once it’s moved so far away it’s approaching Earth from the other side, it turns around and moves away again.

Cruithne from a stationary Earth position

Horseshoe orbits are actually quite common for moons in the solar system. Saturn has a couple of moons in this configuration, for instance.

What’s unique about Cruithne is how it wobbles and sways along its horseshoe. If you look at Cruithne’s motion in the solar system, it makes a messy ring around Earth’s orbit, swinging so wide that it comes into the neighbourhood of both Venus and Mars. Cruithne orbits the sun about once a year, but it takes nearly 800 years to complete this messy ring shape around the Earth’s orbit.

Cruithne close up

So Cruithne is our second moon. What’s it like there? Well, we don’t really know. It’s only about five kilometres across, which is not dissimilar to the dimensions of the comet 67P/Churyumov-Gerasimenko, which is currently playing host to the Rosetta orbiter and the Philae lander.

The surface gravity of 67P is very weak – walking at a spirited pace is probably enough to send you strolling into the wider cosmos. This is why it was so crucial that Philae was able to use its harpoons to tether itself to the surface, and why their failure meant that the lander bounced so far away from its landing site.

Given that Cruithne isn’t much more to us at this point than a few blurry pixels on an image, it’s safe to say that it sits firmly in the middling size range for non-planetary bodies in the solar system, and any human or machine explorers would face similar challenges as Rosetta and Philae did on 67P.

Possible clash: Venus J.Gabás Esteban, CC BY-SA

If Cruithne struck the Earth, though, that would be an extinction-level event, similar to what is believed to have occurred at the end of the Cretaceous period. Luckily it’s not going to hit us anytime soon – its orbit is tilted out of the plane of the solar system, and astrophysicists have shown using simulations that while it can come quite close, it is extremely unlikely to hit us. The point where it is predicted to get closest is about 2,750 years away.

Cruithne is expected to undergo a rather close encounter with Venus in about 8,000 years, however. There’s a good chance that that will put paid to our erstwhile spare moon, flinging it out of harm’s way, and out of the Terran family.

It’s not just Cruithne

The story doesn’t end there. Like a good foster home, the Earth plays host to many wayward lumps of rock looking for a gravitational well to hang around near. Astronomers have actually detected several other quasi-orbital satellites that belong to the Earth, all here for a little while before caroming on to pastures new.

Secrets: solar system Tashal

So what can we learn about the solar system from Cruithne? Quite a lot. Like the many other asteroids and comets, it contains forensic evidence about how the planets were assembled. Its kooky orbit is an ideal testing ground for our understanding of how the solar system evolves under gravity.

As I said before, it wasn’t until the end of the 20th century that we even realised that bodies would enter such weird horseshoe orbits and stay there for such a long time. The fact they do shows us that such interactions will have occurred while the solar system was forming. Because we think terrestrial planets grow via collisions of bodies of Cruithne-size and above, this is a big new variable.

One day, Cruithne could be a practice site for landing humans on asteroids, and perhaps even mining them for the rare-earth metals our new technologies desperately crave. Most importantly of all, Cruithne teaches us that the solar system isn’t eternal – and by extension, neither are we.