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US plans to answer the lure of Europa

To planetary scientists Jupiter’s icy moon Europa is a Siren, calling out to them across the solar system. With its youthful surface, abundance of water and the tantalising evidence of a moon-wide ocean – it is one of the best chances for us to find life within our solar system. Last week the Europa Clipper mission won some critical support of US congress representatives, who attended a meeting organised by the Planetary Society called ‘The lure of Europa’.

Can you hear it calling you? The beautiful surface of Europa. NASA/JPL/Ted Stryk

But it hasn’t been ‘plain sailing’ for the Clipper mission. In 2013 the planetary science community gathered and put out a decadal plan, citing the exploration of Europa as one of its highest objectives. However, cuts to funding for ‘outer’ planetary research in favour of Mars and the manned space program left many dispirited. The community have powered on, investing energy in lobbying policy makers, and now traction for the Europa mission is building.

So why go back?

Just in the past year there have been two remarkable insights made about Europa, only making its Siren call louder. The first of these was that the Hubble Space Telescope spotted evidence that geysers were shooting up into space from the moons surface. This immediately put Europa in a rather elite category of planetary bodies, ones that we have observed to be doing things! Now along with the ‘Tiger Stripes’ of Enceladus, sulfur volcanoes of Io and magic islands of Titan – the geysers of Europa show that this moon is more than a passive snowball.

The second insight has been a paper that did a ‘reverse jigsaw puzzle’ study of Europa’s surface. Since the Galileo mission returned it’s startling images of the surface of Europa, the features that were most obvious were extensional. Analogous to the mid-Atlantic ridge, these features were interpreted to be extending the ice crust.

The issue was, though, that nobody could see where the crust had contracted to compensate for this. Putting aside the thought that Europa had just got bigger, a recent paper has picked up on a number of lines of evidence for subduction on Europa. On Earth, subduction is one of the main ways the giant plates of crust are destroyed, with one plate being forced under the other. Among the evidence that was picked up from the Galileo images – was the mismatch of features on the surface, leaving the researchers to identify the missing ‘pieces’ of crust that had been pushed under.

Finding the missing pieces of Europa’s crust, this image shows the tectonic reconstruction of part of the surface. NASA/JPL/S. Kattenhorn

Both of these insights have highlighted the fact that Europa’s surface and interior are linked and there are ways and means that material can be brought to the surface from the interior and vice versa. There’s not proof yet that this would extend to the potential ocean below, but it’s tantalising that maybe it hasn’t been locked away from outside influences.

For me, Europa has currently lured me away from home in Australia to Japan. For the next three months I’ll be based at the University of Tokyo where I’m currently recreating bits of Europa in the lab, using high-pressure and low temperature equipment. Chiefly what I’m interested in, is how possible impurities from Europa’s sister moon Io could effect water-ice under these conditions.

Will Clipper be scooping up the Europan surface to investigate the ice crust and its impurities directly? Sadly not, there are no plans for a lander in the Clipper mission. This is mostly because we don’t have good enough images of the surface to plan this yet. But the fly-bys that are currently being planned for Clipper would add greatly to the potential of this happening, with audacious plans to have a lander that could then burrow through the ice.

The Europa Clipper probe, zipping past the icy moon NASA/JPL

But until about 2020, when the hope is that Clipper will launch towards the Jupiter system, there’s a lot of time for me to do experiments yet!

Who are the two new arrivals at Mars?

As I write this, a team of engineers and scientists will be nervously watching the clock (in fact they are probably in their beds not sleeping). They are waiting for the time when the Mars Orbiter Mission (or MOM) will fire its thrusters and start a gravitational pas-de-deux with Mars.

These engineers and scientists are not sat in Huston, but in Bangalore and represent India’s first attempt at reaching the red planet. If they succeed they will become only the fourth space agency, after NASA, the Soviets and ESA, to achieve such a feat.

Mangalyaan Mars Orbiter Mission MOM Vipal M.B.

Mostly the MOM spacecraft is a technology mission, designed to test the systems and space engineering of the craft as well as the technology the Indians have developed to complete it.

It has, however, carried a few scientific instruments mostly to investigate Mars’s atmosphere. One key scientific target of MOM, is to search for the signal of methane in Mars atmosphere – a potential sign of life hiding somewhere on the planet.

A potential ‘whiff’ of methane in the atmosphere of Mars was first detected in 2004, by the ESA Mars Express mission. But counter to these observation, as MOM took off in November 2013, was the fact that just months before the Curiosity rover had looked for methane and did not find any. So there’s fantastic potential that any observations from MOM will really add to this debate.

The project has not been without controversy, and has sparked debate as to how a country racked with poverty, can afford to send missions to space. Not only is it expensive sending spacecraft to Mars, but also very risky – as the Chinese, Japaneseand NASA space agencies have found to their cost.

Having said that, NASA has learnt from its difficulties with other Mars missions, and made the insertion of MAVEN into the gravitational well of Mars look ‘old hat’.

Arriving at Mars orbit on Sunday, MAVEN’s (which is a rather forced acronym standing for Mars Atmosphere and Volatile EvolutioN) scientific goals will focus almost entirely on the red planet’s atmosphere. One of the questions it is hoping to answer is ‘Has all of Mars’ water escaped to space?’

How MAVEN will go about searching for Mars’s lost water.

Water on Mars is an on-going issue - we now have planet-wide images of Mars showing, what seem to be, water cut features. On top of this the rovers on the ground are picking up evidence for minerals that (from our current understanding), could only have been formed through some interaction with water.

Evidence is mounting that it is not trapped underground, with the results from the ground penetrating radars carried by the Mars Express and NASA’s Mars Global Surveyor. Hence, the next ‘sink’ of the water to be investigated is space itself – and that’s the job MAVEN has turned up to do.

So fingers crossed for a couple of hours’ time, when MOM tries to wriggle into orbit. You can watch the live feed from the Indian Space Agency here http://webcast.isro.gov.in/. I hope that it makes it, and together with MAVEN can find another piece to the puzzle that is Mars’s geological history.

So now all the Lego scientists are women, how is reality building up?

Box front of the new LEGO Ideas “Research Institute” set LEGO

So who went and bought some of the new Lego mini figures?

Aren’t they super? The set, which is part of the new Lego “Research Institute”, features a female chemist, paleobiologist and astronomer. It has sold out in days, which probable tells you something of the demand for such positive stereotypes. The set came about from a suggestion from Ellen Kooijman on the Lego ideas site, and was accelerated by a seven year old who also noticed the male-bias in Lego figures.

It is fantastic to have new champions of women in science on board. But, I’m sat here at the International Conference on Women in Physics and all I can think about is the backwards steps that Australia has taken when it comes to women and science, and correspondingly women in science. Alarmingly this has been rather rapid too. There’s evidence that the current cuts to science funding are disproportionally affecting women.

On the longer term, the amount of girls in Australia taking two science subjects to the end of high school has dropped. This is usually seen as pointer to them carrying on with science subjects post-18, and this concern has been noted by the Chief Scientist’s office .

I sat today listening to updates of the status of women in physics from 53 other countries, and some stories really stood out. In Iran and Egypt, for instance, there are more female students at undergraduate level in physics than men. In Finland, women physicists are held back by the culture of meetings held in gender-segregated saunas. And when I asked a Japanese delegate about when she saw the barriers to increasing on the 5.7% female membership of the Japan Physics Society she responded starkly: “From birth.”

A bit of a loose trend did seem to emerge though, many countries (Australia, at present included) report an about 30% female population of physicist right up to PhD level. There it drops off. This is not new news, I’ve written about it before, and this is not just confined to physics. What was really interesting was learning today what the Netherlands are doing to address this.

As a country, the Netherlands noticed that they didn’t have enough physicists and chemists(!), and were concerned that this would effect their economic future. So to up their numbers, they decided to appeal to the underrepresented 50% of their population, women.

The Dutch government has funded 88 tenure-track positions, and has set the target that 40% of these should be filled by women – in fact they mandated that 20 of these positions could only be filled by women. I asked the Dutch delegates about how this scheme had been received in the community, and they did say there had been some resistance.

But they explained that the idea of such a mandate had been motivated by the success of fellowship schemes that only recruited women, improving the status of the departments running them.

Quite and aggressive tactic perhaps? It is certainly the most head-on way I have encountered of trying to stop up the “leaky pipeline” of women in science. But, are the more subtle ideas, such as the Lego figures, going to be more constructive on the longer term to remove the gender bias in our society?