ExoMars landing site 1: Europe goes to Mars

This post was contributed by Dr Peter Grindrod, of Birkbeck’s Department of Earth and Planetary Sciences. A longer version was originally published on his personal blog.

If you had to pick just one place to find life on Mars, where would you go? For the last twenty years, exploring Mars has been a case of “follow the water”. The thinking goes that without water there won’t be life. That could well be true, but it’s only part of the story.

An artist’s impression of the European Space Agency ExoMars rover. Credit: ESA

An artist’s impression of the European Space Agency ExoMars rover. Credit: ESA.

In the 1970s John Guest, my former PhD supervisor, worked on the NASA Viking mission to Mars. Twin orbiters, twin landers, nobody builds missions like that these days. As a geologist, John helped to decide where one of the landers would touch down. John told me how he and his friend Ron Greeley only had a couple of days’ worth of images from the orbiters, at a frighteningly low-resolution by today’s standards. They had to choose a landing site that wouldn’t leave the landers in pieces and would still be scientifically interesting. I thought that the pressure and responsibility of that decision must have been massive. John seemed nonplussed by my concern.

The first image returned from the Viking 2 lander on the surface of Mars. Credit: NASA.

The first image returned from the Viking 2 lander on the surface of Mars. Credit: NASA.

I remembered this story because the European Space Agency has recently asked the same question again, and people are trying once more to answer it.

But this is no longer the Mars that Ron and John knew with Viking. Back then Mars was a world of giant volcanoes and enormous rift canyons – planet-scale processes. Today we talk about fluvial sediments and river deltas, redox reactions and energy gradients, clay minerals and organic compounds. We talk about it like we do the Earth.

And we no longer have to rely on just a handful of low-resolution images and a rushed decision. Instead we have hundreds of terabytes of data at our fingertips to call upon in the search.

Technological advances have changed the way we see and explore Mars. The latest images from the HiRISE camera can see things on the surface, from orbit, that are only 25 cm across. It can make out individual rocks. In fact, if you look at modern images of the Viking landing sites, it’s pretty obvious that we would never land somewhere like that again. My god the boulders! It’d be considered far too unsafe nowadays, but I guess that’s testament to the engineering of the Viking landers.

How the decision will be made this time is very different too. It’s a reassuringly long and detailed process these days, carried out in the open by many different scientists.

After the initial call for landing sites back in December, the first discussion workshop will be held in Madrid later this week. Here Mars scientists will come together to champion their own site, debate the pros and cons of others, and generally make sure that no one place is missed. A few months later a shortlist of three or four sites will be drawn up.

Over the following few years, each of these sites will be studied in possibly more detail than any other place on Mars. And then, the year before launch, the European Space Agency will make the final decision.

And I can’t say I envy them. It will come down to a delicate yet familiar balance between engineering constraints and scientific goals.

As it happens, because of the way that we tend to land on Mars, most of the planet is immediately ruled out. All landers use a parachute to slow themselves down as they come through the thin atmosphere. To make sure that the parachute has enough time to do its job, the landers need to touch down at as low an elevation as possible – the more atmosphere it travels through the longer it has to slow down. So, there go all the interesting high areas.

Next, because it’s solar-powered (I presume – there might be communication considerations too), the ExoMars rover has to land in a latitude band straddling the equator that’s only 30 degrees from top to bottom. That’s the polar caps out then.

A blink animation of a global map of the topography of Mars, showing the elevation and latitude constraints when selecting a landing site for ExoMars. Credit: Peter Grindrod.

A blink animation of a global map of the topography of Mars, showing the elevation and latitude constraints when selecting a landing site for ExoMars. Credit: Peter Grindrod.

Finally, landing on another planet isn’t a pinpoint process. There’s a certain probability of landing within a given distance of the target. This uncertainty is known as the landing ellipse, and for ExoMars it’s the equivalent of trying to land in Manchester, but knowing you might end up in Liverpool or Sheffield. Can you imagine the horror? The ellipse for ExoMars is also over four times the size of the ellipse for the recent Curiosity landing, so forget any ideas you had of going to the sites rejected for that mission.

So that doesn’t leave all that much. And we haven’t even started yet on the actual scientific goals of this mission, essentially why we’re going there.

The goals of ExoMars are pretty clear, and pretty bold.  The first though has the most control on choosing where to land: to search for signs of past and present life on Mars.

Most of the evidence that we’ve gathered since Viking says that the earlier parts of Mars’s history were the most hospitable to life. It was certainly wetter, probably warmer, and with a much thicker atmosphere than today. So ExoMars has to land somewhere with ancient rocks that are a record of that environment. That means landing somewhere older than 3.6 billion years old. That’s about the same age as some of the oldest rocks on Earth.

And bearing in mind what we know about life on Earth, there has to be evidence of water too, both in the shape of the landscape and in the minerals in the rocks. ExoMars is going to drill two metres into the sub-surface, as exposure to the radiation at the surface might have broken down any evidence of life. So the rocks to drill, core and study are soft, sedimentary rocks that can be read like a history book. Finally, there have to be as many of these targets as possible close to the centre of the ellipse, and as little dust cover as possible.

Over the last few months I’ve been part of a group of UK-based scientists who have been trying to help answer the question of where to land. We knew that other people would propose most of the other well-known sites. So we’re not exactly rooting for the underdog, rather making sure that nowhere is missed. From our own list of about thirty sites, we narrowed it down to just two that met all of the criteria, and which we’ve now sent off for consideration with everybody else’s suggestions.

Later this week we’ll be in Madrid discussing all these sites. I’m looking forward to it, and have to admit that it’s exciting and humbling to have even a small part in the process.

But it’ll be sad for me too. Both John, who was a mentor and friend, and Ron died recently, less than a year apart. They’ll both be missed. It’s strange to think that they’ll both be missing the latest stage of our exploration of Mars that they helped to pioneer.

I’m sure we’ll raise a glass to them. And I hope that wherever ExoMars does land, it’ll be an adventure worthy of future story-telling.

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Another Darkness, Another Dawn: A History of Gypsies, Roma and Travellers

This post was contributed by Dr Becky Taylor, a lecturer in Birkbeck’s Department of History, Classics and Archaeology.

The Roma are back in the news: the Daily Mail has published an article claiming that a Bulgarian Roma woman has schooled ‘hundreds of children’ in the art of pickpocketing; government promises to clamp down on ‘welfare tourism’ in the wake of the dropping of border controls from Bulgaria and Romania have been tied sometimes implicitly, often explicitly, to expected ‘invasions’ of Roma. Once again, it seems, society’s wider insecurities about social change have found a scapegoat in Europe’s most marginalised and vilified minority. This is nothing new: in 2014 scaremongering about Bulgarian Roma may be a way of expressing deep seated fears over migration, the expansion of Europe and the lack of a democratic voice; in early modern Europe repression targeting ‘Egyptians’ and ‘counterfeit Egyptians’ was means for regimes trying to control the rapid rise in vagrancy and the social uncertainty caused by wars and religious upheavals.

Romani peoples are rarely seen as having a place in a country, either geographically or socially, no matter where they live or what they do. Part of their marginalisation stems from the fact that they are excluded from mainstream histories. At the same time, they are rarely granted a separate history, but rather seen to exist in a timeless bubble, unchanged and untouched by modern life. If some Roma or Gypsies are seen as deviant, thieving and untrustworthy still others – often existing more in the realm of story books and imagination – are depicted as living a timeless life of constant nomadism; innately exotic, musical, most likely living in bow-topped caravan, ‘here today, gone tomorrow’, untouched by the cares of modern life.

Another Darkness, Another Dawn A History of Gypsies, Roma and TravellersMy recent book, Another Darkness, Another Dawn: A History of Gypsies, Roma and Travellers (Reaktion, 2014) is an attempt to move beyond such stereotyping and to write not only a history of peoples most often known as Gypsies, but also to write their history into the mainstream. Understanding their history means tracking the gradual migration of peoples whose descendants became Romani, from India across the Persian empire and into Europe via Byzantium. It also means reflecting on the vast array of ways in which they have lived: while some groups may have been perpetually nomadic, large numbers – across history and place – often travelled for the summer and settled in the winter; still others settled permanently in particular villages or parts of towns. Central to Romani experiences has been their ability to find gaps and spaces in which they might continue to exist and even sometimes to thrive. Their economic activities often exploited niches which settled communities were unable to fulfil; and their resilience and willingness to live on the margins has enabled them to survive waves of repression.

Writing this history was also to take in the founding and contraction of empires, Reformation and counter-Reformation, wars, the expansion of law and order and of states, the Enlightenment and the increasing regulation of the world – it is as much a history of ourselves as it is a history of ‘others’. So long positioned as outsiders, in fact genetic mapping as much as the genealogies constructed by the nineteenth-century Munich police, show the extent to which, whether settled or mobile, Romani peoples’ heritages have long been as intimately bound to the European population as they are to an original Indian ancestry. Evidence from the Venetian as well as Ottoman empires shows how they rapidly became integrated into their social, feudal and military systems. And indeed, that the Ottoman empire was quite capable of managing nomadism and taxing nomads is revealing of the paucity of imagination of modern bureaucratic states with their insistence on a fixed address as a key indicator of citizenship.

If exploring the history of Romani peoples was a way of holding up a mirror to the societies in which they have lived, it was also a salutatory lesson into the dangers of believing in a progressive view of history: things don’t always get better, especially if you belong to a marginalised ethnic group. But neither were they always necessarily as simple as they first appear. Carrying out the research for this book showed how the enslavement of Gypsies coexisted under the Ottomans with remarkable cultural diversity and autonomy; how branding, mutilations and ‘gypsy hunts’ occurred at the same time that Gypsies established themselves across Europe; and how despite developments in education and attitudes towards minorities the modern world has failed to bring anything like acceptance of the place of Romani peoples within its societies. The book takes its name from the words of Ilona Lacková, a Slovakian Roma and Auschwitz survivor: ‘It’s the end of the war, we’ve survived. After darkness comes the dawn. But after every dawn also comes the darkness. Who knows what’s in store for us’.

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Parents in Parliament: The Motherhood Trap

This post was contributed by Dr Rosie Campbell, a Senior Lecturer in Birkbeck’s Department of Politics and Professor Sarah Childs (University of Bristol). It was originally published on the British Politics and Public Life blog.

Men’s over-representation and women’s under-representation in the UK Parliament is pretty well known, even if the public sometimes over-estimates just how many women MPs there are, bedazzled by their bright clothing in the Chamber.[1] In fact, men outnumber women by more than 4:1. (In his 2009 survey conducted by YouGov, Professor Phil Cowley (Nottingham) asked respondents what they thought was the correct percentage of women MPs was. At the time the average response was 26% when the actual figure was closer to 20%.)

Some people may not find this particularly troublesome. Lord Hurd has recently been cited saying that there is a “ludicrous” obsession with ensuring there is equal representation of men and woman in parliament and other areas of public life. We believe very strongly that a diversity of background and experience does matter. And there’s another serious flaw with the Hurd line of reasoning. He says that if voters didn’t want a “good looking chap from a public school” as prime minister they wouldn’t keep choosing them. But the reason feminists have campaigned for All Women Short-lists as a means to get more women at Westminster is precisely because it’s political parties not voters who choose our candidates and party leaders. We the voters don’t get to choose our parliamentary candidates, and therefore who our MPs, are. The reasons there are too few women in politics stems from both a lack of demand for and supply of women candidates: voters don’t punish women candidates. But in the absence of equality measures such as Labour’s All Women’s Shortlists, parties are much less likely to select women in winnable seats, even if fewer women seek selection as parliamentary candidates overall.

Having children is frequently cited as a barrier that holds women back from seeking parliamentary selection. But of course not all women are mothers. And both men and women are parents. So we need to question whether the problem is less about the equal representation of men and women – or parents and non-parents – and perhaps more about the exclusion of mothers?

Until now, the UK Parliament simply did not know how many mothers or fathers sat on its green benches. During the new Labour years, and again since 2010, a number of women MPs have given birth: the latest being the Liberal Democrat Minister Jo Swinson, who is currently facing criticism for wanting to have her child with her in the division lobby. We doubt that the vocal hostility to the needs of a new mother, that her comments have generated, are likely to increase the supply of mothers seeking selection for the 2015 general election.

In our survey (supported by the Speaker of the House of Commons and the Commons Diversity and Inclusion Unit )of MPs in 2012 we found a startling set of facts about mothers and fathers in Parliament:

• 45% of women MPs have no children, compared to 28% of male MPs, and compared to an average of about 20% of the population who remain childless. (According to the Office for National Statistics 20 percent of women born in 1966 remain childless.)
• Of all MPs with children, male MPs have on average 1.9 children, whilst women MPs have on average only 1.2
• The average age of women MPs’ eldest child, when they first entered parliament, was 16 years old ; the average age of men MPs’ eldest child when they first entered parliament was 12 years old
In sum: women MPs are (1) less likely to have children than male MPs; (2) more likely to have fewer children than male MPs; and (3) enter parliament when their children are older than the children of male MPs.

These staggering differences are clear evidence that there are serious barriers to Parliament for those with caring responsibilities, most often mothers.

Reactions to these statistics will likely vary depending on whether you believe that the House of Commons should look like the society it represents for reasons of justice; or whether you think that good-looking public school educated men are equally capable of understanding the complexities of juggling work and family life. There will be those who have no fear that without mothers in Parliament the soaring costs of childcare and the disproportionate effect of the economic crisis on women in low paid and part-time work (mostly mothers) will reach the top of the political agenda. We’re not so sure. And that’s why we want more mothers in Parliament.

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Responses to storm damage: research evidence for early warning and evacuation planning

This post was contributed by Dr Sue Brooks, Senior Lecturer in Physical Geography in Birkbeck’s Department of Geography, Environment and Development Studies.

Few people can have failed to notice the high flood incidence over the past few weeks across the UK. One particularly newsworthy event was the storm on 5-6 December 2013 that brought widespread coastal flooding into the southern North Sea and spread destruction across Europe.

Flooding on the North Norfolk Coast following the storm of 5-6 December, 2013 (photos courtesy of Mike Page)

Flooding on the North Norfolk Coast following the storm of 5-6 December, 2013 (photos courtesy of Mike Page)

Photo courtesy of Mike Page

Photo courtesy of Mike Page

The worst in 60 years?

The 5-6 December storm forced evacuation of over 10,000 homes in Norfolk and Suffolk, flooded over 1, 400 properties and caused houses to collapse into the sea. It appears to have been the most serious storm for 60 years, following the notorious storm surge of 1953 when over 2000 people lost their lives. But it could happen again next week, next month or next year – so we need to heed the lessons from both events.

Lessons from 1953

So how do these two storm events compare, why did the earlier event lead to such greater human cost and what can new research on the 2013 event tell us?

The 2013 and the 1953 storms arose in similar ways involving deep low pressure systems tracking down the North Sea. But the 1953 event, with eight metre waves, also had devastating consequences because it struck over a weekend. Early warning and evacuation planning were piecemeal, with the radio warning ceasing to transmit from midnight on the Saturday and the offices set to receive telegrams being shut for the weekend. People had very little warning. In 2013, in view of lessons from 1953, the sea encountered strengthened and heightened flood defenses, better early warning and better co-ordinated evacuation planning.

How our research is providing new lessons for early warning and evacuation planning

Following the 5-6 December storm we wasted no time recording its coastal impact. A team of researchers from Birkbeck and the University of Cambridge documented water levels around the coast of East Anglia. We used debris drift lines (we had to be quick as the tidy up was swift), erosional notches in banks and cliffs (these are preserved for longer), water marks on buildings and anecdotal evidence from local residents to position the water levels.

Drift lines and water lines on buildings in the immediate aftermath of the storm recording water elevations at Burnham Overy Staithe, Norfolk (photo taken on 6th December, 2013 by T Spencer)

Drift lines and water lines on buildings in the immediate aftermath of the storm recording water elevations at Burnham Overy Staithe, Norfolk (photo taken on 6th December, 2013 by T Spencer)

Water line evidence on public toilet block at Brancaster Beach, Norfolk following 5-6 December storm surge (photos taken on 6th December, 2013 by T Spencer)

Water line evidence on public toilet block at Brancaster Beach, Norfolk following 5-6 December storm surge (photos taken on 6th December, 2013 by T Spencer)

Brancaster Beach Sign

We used a Global Navigation Satellite System (GNSS) accurate to 20mm to determine the precise water elevations. We found 2013 water levels very similar to those of 1953, and in places 1953 levels were exceeded. More exciting was to find considerable variation in the water level around the coast, about two metres difference in North Norfolk.

Why was the water level so variable?

Water levels recorded in tide gauges in sheltered locations show how the surge level became progressively higher and occurred later as the storm moved southward (see diagram). Surge models can predict this effect and can thereby generate early warning and evacuation procedures against imminent flooding. However, they can only operate at this broad regional scale.

Recorded and predicted water level at locations along the east coast of UK, 5th-6th December 2013 (based upon data from the National Tidal and Sea Level Facility, provided by the British Oceanographic Data Centre and funded by the Environment Agency)

Recorded and predicted water level at locations along the east coast of UK, 5th-6th December 2013 (based upon data from the National Tidal and Sea Level Facility, provided by the British Oceanographic Data Centre and funded by the Environment Agency)

Strong, persistent winds generate high waves, also a factor in coastal damage. Waves were four metres at the Blakeney overfalls wave rider buoy (10 km offshore). Waves are considerably modified by the coastal setting. Along the North Norfolk Coast they were able to add significant force on top of already elevated water levels.

The collapsing cliffs at Covehithe, Suffolk (research will quantify the land loss in the 5-6 December, 2013 storm surge) (photo taken on 11th December, 2013 by SM Brooks)

The collapsing cliffs at Covehithe, Suffolk (research will quantify the land loss in the 5-6 December, 2013 storm surge) (photo taken on 11th December, 2013 by SM Brooks)

Further around the coast in Suffolk we found evidence for cliff erosion, arising from wave action at the cliff base (Brooks et al., 2012). Our initial findings suggest that water levels and wave action reached almost four metres ODN (Ordnance Data Newlyn, which approximates to mean sea level), producing notching and cliff collapse. Loss of land and homes through cliff retreat is irreversible and cliff retreat can continue long after the surge event has happened.

What lessons can we take forward from 2013?

  • Water elevation differences affect a property’s flood risk.
  • Homes and businesses need to have information on their specific vulnerability.
  • Models provide general predictions of timing of surges and open sea water levels.
  • We don’t currently consider how surges interface with the coastal setting encountered.

From 2013 we have now learnt that in coastal settings such as North Norfolk and Suffolk, the barrier islands, dunes and gravel spits, interspersed with tidal inlets with marshes and mudflats and separated by eroding cliffs make for huge variability in the potential for the sea to ingress and flood land, as well as to cause cliff retreat through wave action.

Our results show there are still lessons to be learned that could help prevent future societal and environmental damage that accompanies storm surges.

The team’s initial assessment is published in Nature and further information is available here.

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