Further evidence has emerged that Mars still has some liquid water

Scientists analysing images of Mars have found even more signs that, in rare circumstances, Mars may have water flowing across its surface.

Mars is supposed to be a dead, dry planet. There are clear signs that liquid water used to flow across its surface - remember Nasa mocking up that video of the Mars of 3.7 billion years ago? - but one of the Curiosity rover’s jobs right now is to investigate what we take to be ancient river bed.

This makes it very surprising indeed that scientists saw dark, water-like streaks in the red dust, in 2011. This should not be happening on a planet with no atmosphere.

To be clear, this isn’t proof that there’s liquid water on Mars - it’s just that we’ve seen something that looks a heck of a lot like liquid water. Here’s a slideshow of eight images showing what we’re talking about, provided by Nature:

Those black lines, as spotted by the Mars Reconnaissance Orbiter, are known as “recurring slope lineae”, and they darken the Martian soil just as water darkens soil on Earth. They were originally found two years ago at seven sites in the highlands of southern Mars, at middle latitudes which warm up in the summer and freeze again in the winter.

This latest study, by the same team of planetary scientists led by Alfred McEwen of the University of Arizona in Tucson, has found a further 12 sites with streaks, all on or near the equator. The equator has roughly the same temperatures year-round, and that means that - if there’s liquid water flowing on the surface - there must be a mechanism in place to replenish it. Mars’ low atmospheric pressure means that liquid water on the surface should sublimate into a gas almost immediately.

We now know that there’s quite a lot of water on Mars, be it frozen on the surface at the poles, under the surface elsewhere on the planet, or bound up with the soil itself. The implication of a flowing water source is that it might be the most likely location of life that still exists on Mars - but, conversely, that also makes it more crucial that we don’t send improperly sterilised probes there. If those Earth microbes are to survive anywhere on Mars - and scientists recently discovered a whole new species of microbe that could survive in even the most sterile of spaceship construction labs - then they’ll survive on these slopes.

It's also exciting for future colonists, who will save on energy if they don't have to heat up ice for drinking water. Our best chance of figuring out the exact nature of these lines on Mars is from afar, with the Mars Reconnaissance Orbiter, until we can decide what further action to take. Perhaps even the first colonisers, whoever they be (maybe it'll be Mars One, who want to send people there on a one-way mission starting from 2024) will be able to take advantage of that water source.

Dark streaks on Mars that may be water. (Image: NASA/JPL-Caltech/U. of Arizona)

Ian Steadman is a staff science and technology writer at the New Statesman. He is on Twitter as @iansteadman.

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Beesic Instinct: Labour wants to protect the bees from Brexit

Leaving the EU could weaken protections, which is a shame because politicans have a lot to learn from hive behaviour

No more bumbling around from Labour: the Party is now firmly pro-Bee. Their new manifesto says they would ban the controversial pesticides, known as neonicotinoids or “neonics”, from the UK:

The pledge is not just great news for bees, whose nervous systems are attacked by the chemicals, but for admirers of bees' elegant political decision making too. In fact, if our politics was more bee-like perhaps it would bug us less.

Bees, it turns out, are skilled in the political arts. When honey bees have to move to a new hive they send “scouts" to check out the options - a cosy crevice in your shed perhaps. The scouts then relay their findings to their comrades with a “waggle dance” up the honeycomb walls. Their sequence of steps indicates a site’s location, and if their opinion of your shed is not so hot, they’ll only bother to repeat their dance a couple of times. If they love it, they can dance a few hundred.

The longer a bee dances, the larger her audience grows. Her fellow scout bees can then follow the directions and visit the venue themselves. On their return, they perform their opinion for others. Eventually a hive should end up with a critical mass of the creatures all dancing for the same place. At that point, the entire hive takes flight to its new, democratically elected, home. Talk about waxing lyrical. 

Now just think about what such a system could do for British politics? Leaving aside the joyful prospect of our Right-Honourables jigging their way through parliament, would bees be vague about what kind of EU relationship they were choosing? No way. Would they have been swayed by dodgy facts? Nope. 

But, wait, what’s that I hear you say? – it’s not real democracy if only the scout bees get a vote! Fair point. But in that respect, neither is our own: just take 16 year-olds or foreign nationals. 

Plus the sad truth is that leaving the EU is putting the UK's capacity for strong, scientific decision making in doubt - not least over which pesticides are safe to use.

At present, The European Food Saftey Authority evaluates the safety of the substances proposed in new “plant protection products” and shares the results among the member states. In 2013, its findings led the European Commission to restrict the use of three key neonictides which the EFSA warned posed a “high acute risk” to honey bee health. This science has recently been reviewed by the EFSA and may see the restrictions extended to a complete ban

In the event of Brexit, the UK will have to decide on whether or not to maintain, extend or reduce EU rulings on pesticides. Labour's call for prohbiition is in line with calls from seventeen of the UK’s leading environment and conservation groups (the Green Party already pledged to ban neonoictinoids in their 2015 campaign). But while the Conservative government says it will take a "risk based" approach to the matter, it is under pressure from pesticide and farming groups to relax present regulation. In 2013 it also voted against the EU’s partial ban.

The even wider question, however, is how Britain will conduct scientific reviews and licensing in future. Dave Timms, senior policy campaigner for Friends of the Earth, is concerned about what our future relationship to the EFSA's review process will be: "You've got so many chemicals coming up for review all the time that member states take it in turn to be rapporteurs - and that process of sharing the science, sharing the effort, could be lost if we leave."

Even Defra has highlighted the problem of repatriating such decisions to the UK: "some areas (such as chemicals or ozone-depleting substances) might present more challenges than others because they are currently delivered by EU agencies, systems or resources,” it said in evidence presented for a recent government report.

The need for decisions based on shared and transparent scientific evidence has thus arguably never been greater. Otherwise we risk a situation in which, as Dr Elli Leadbeater of Royal Holloway told the NS, “evolution seems to have found a better solution than we have.”

India Bourke is an environment writer and editorial assistant at the New Statesman.

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