Watch: this is what Mars looked like 3.7 billion years ago

While it seems to be a dead planet today, in the past the Red Planet would have felt very much like home to us - with clouds, oceans and blue sky.

We are nearly as certain as it is scientifically possible to be that there isn't any life on Mars. There is still every chance that there was life at some point, and we might still find it. The landscape is clearly marked with signs of water erosions, and Curiosity and Opportunity (the two rovers currently trundling around up there) have taught us a huge deal about its geology - including the discovery of "abundant" traces of water in Martian soil. Mars clearly had a lot of liquid water on its surface at some point.

The question, though, is why it doesn't have lakes, rivers, oceans, and streams any more - and what it looked like when it did. Nasa's Goddard Space Flight Center has taken a stab at visualising the Martian world of 3.7 billion years ago ahead of its Mars Atmosphere and Volatile Evolution (or Maven) mission which takes off on 18 November, producing a quite lovely animation:

It looks just like Earth because back then Mars had two Earth-like things going for it that it doesn't any more. Firstly, the habitable zone around the younger, larger Sun - that's the range of orbits around any star within which is neither too hot nor too cold for a planet to have liquid water on its surface - was further out, and secondly Mars also had a thick atmosphere. Without the pressure that comes with an atmosphere, liquid water will either freeze solid or evaporate instantly, as happens currently on Mars.

The habitable zone moving inwards had the happy side effect of making the Earth habitable, and eventually - as the Sun enters its final few billion years and swells in size, becoming a red giant - that zone may well move out further again and give Mars a chance at hosting liquid water again. That is, if it gets an atmosphere too, and that's the mystery. We know it must have been there once, but it isn't there now, and we can't be sure why that it. We're not even totally sure if the atmosphere's disappearance is wholly responsible for the transformation of Mars from wet, blue globe like you see above to dusty, red ball that looks like this:

That's a picture taken by the Curiosity rover.
Credit: NASA/JPL-Caltech/MSSS

One possibility for what happened to the atmosphere is that Mars' core cooled down and stopped generating both plate tectonics and a magnetic field, which would have formed a barrier that would have stopped too many atmospheric particles being stripped away into space by the solar wind. Without active volcanoes to generate gases to replace the lost particles, you end up with the situation today where the surface pressure on Mars is, on average, 0.6 percent that of what you'll find on Earth. That's equivalent to being 35km up in the sky on Earth, nearly twice as high as where commercial aeroliners fly.

Maven is an orbiting probe that will launch on 18 November and try to uncover more data about Mars' atmospheric past. Here's Joseph Grebowsky, the mission's project scientist:

Studies of the remnant magnetic field distributions measured by Nasa's Mars Global Surveyor mission set the disappearance of the planet's convection-produced global magnetic field at about 3.7 billion years ago, leaving the Red Planet vulnerable to the solar wind. 

Maven has been designed to measure the escape rates for all the applicable processes and will be able to single out the most prominent. Previous remote Mars observations from orbiting spacecraft have observed the geological features that have been used to estimate the amount of water that did exist and have analysed the global distribution of water ice and surface chemistry to infer that water was lost through time. Mars Curiosity rover has the ability to analyse the chemical composition of the solid surface, which contains information of the atmospheric composition during the formation of the planet, in particular the isotope ratios, the lower atmosphere composition, and the current gas exchange with surface reservoirs. MAVEN is going to measure the current rates of loss to space and the controlling processes. Given the lower-atmosphere information and the nature of the escaping processes, one can extrapolate from current conditions into the climate of the past.

The probe will reach Mars in September 2014, and is scheduled to work for one Earth year on its mission of uncovering more Martian secrets.

Not Earth, but Mars before it lost its atmosphere. (Image: Nasa)

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

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Your life's work, ruined – how storms can wipe out scientific research in an instant

Some researchers face the prospect of risking their own lives to save valuable scientific research that could benefit future generations.

Before the autumn of 2012, if you went into the basement of New York University's School of Medicine in Manhattan, you would find a colony of more than 3,000 live mice. This was the collection of Gordon Fishell, the associate director of the NYU Neuroscience institute, which he had spent more than 20 years building up, and which he was using to discover how neurons communicate with other cells.

As Hurricane Sandy began to approach New York State, Fishell and his colleagues, like others in the city, made preparations for the onslaught. This meant leaving extra food and water for their colonies, and making sure that emergency power was on.

But no one anticipated the size and intensity of the hurricane. On the day it finally arrived, Fishell was forced by the weather to stay home, and to his horror he saw that his lab was now in the path of the storm. As he wrote later in Nature magazine: "We were done for. It was obvious that our labs were in great danger, and there was nothing I could do." All of Fishell's mice drowned. Furthermore, scientific equipment and research worth more than $20m was destroyed.

In seeing years of academic work wiped out by a storm, Fishell and his colleagues at the School of Medicine are not alone. In 2001, Hurricane Allison, a tropical storm turned hurricane, had caused similar devastation at Texas Medical Centre, the world's largest such research centre, inflicting at least $2bn in damages. In 2011, the Japanese tsunami hit Tohoku University’s world-renowned Advanced Institute for Materials Research and destroyed some of the world’s best electron microscopes, as well as $12.5m in loss of equipment.

Such stories used to be seen as unique and unfortunate incidents. But the increasing incidence of extreme weather events over the last 20 years has highlighted the dangers of complacency.

Not only do facilities affected by natural disasters lose decades of irreplaceable research, but many contain toxic chemicals which could be potentially deadly if released into the water or food supply. During the 2007 floods in the UK, a foot and mouth outbreak was traced back to a lab affected by heavy rain. In Houston, during the recent Hurricane Harvey, leakages from industrial facilities contaminated the floodwater. 

Gradually, university deans and heads of research facilities in the United States have realised that the Federal Emergency Management Agency (FEMA) is badly prepared for this kind of problem. "They had never thought of how to deal with a research loss," Susan Berget, the vice president of emergency planning at Baylor College of Medicine told Nature in 2005. "To them, transgenic mice are a foreign concept."

It therefore falls on universities, local communities and regional governments to ensure they are adequately prepared for disasters. A common complaint is the lack of guidance they receive. 

Often, researchers who choose to save valuable scientific research are putting their lives at risk. One particularly harrowing story was that of biochemist Dr Arthur Lustig, who spent four days in his Tulane university laboratory before being evacuated to a shelter. Despite his tenacity, he lost more than 80 per cent of his work on yeast strains, carried out over 20 years, to flooding caused by Hurricane Katrina.

Other than the immediate, heartbreaking effects of losing research, natural disasters also pose a threat to future investment. If a region is increasingly seen as not disaster resilient, it reduces the amount of federal and private funding for groundbreaking research, as well as applications from prospective researchers.

A recent report in the journal of the National Academies of Science, Engineering and Medicine quantified this link. It found that varius tropical storms led to as many as 120 researchers losing their livelihoods. In one instance, a psychology internship for high schoolers was discontinued. 

Disasters like hurricanes and tropical storms are usually thought of as high risk but low probability events. As Bill McKibben noted in the Guardian, Hurricane Harvey was a once in 25,000 years kind of storm, but the “normal” measurements of incidence cannot necessarily be held as true anymore. Just like the rest of us, researchers will have to be prepared for every possibility.