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Mars

November GeoRoundUp: the best of the Earth sciences from around the web

November GeoRoundUp: the best of the Earth sciences from around the web

Drawing inspiration from popular stories on our social media channels, major geoscience headlines, as well as unique and quirky research, this monthly column aims to bring you the latest Earth and planetary science news from around the web.

Major stories

Earth’s red and rocky neighbor has been grabbing a significant amount of attention from the geoscience media this month. We’ll give you the rundown on the latest news of Mars.

The NASA-led InSight lander, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, touched down on the Red Planet’s surface last week, causing the space agency’s Jet Propulsion Laboratory (JPL) control room to erupt in applause, fist pumps, and cool victory handshakes.

The lander, equipped with a heat probe, a radio science instrument and a seismometer, will monitors the planet’s deep interior. Currently, no other planet besides our own has been analysed in this way.

While scientists know quite a bit about the atmosphere and soil level of Mars, their understanding of the planet’s innerworkings, figuratively and literally, only scratches the surface. “We don’t know very much about what goes on a mile below the surface, much less 2,000 miles below the surface down to the center,” explains Bruce Banerdt, a scientist at JPL, to the Atlantic.

By probing into Mars’ depths, researchers hope the mission gives insight into the evolution of our solar system’s rocky planets in their early stages and helps explain why Earth and Mars formed such different environments, despite originating from the same cloud of dust.

“Our measurements will help us turn back the clock and understand what produced a verdant Earth but a desolate Mars,” Banerdt said recently in a press release.

The InSight lander launched from Earth in May this year, making its way to Mars over the course of seven months. Once reaching the planet’s upper atmosphere, the spacecraft decelerated from about 5,500 to 2.4 metres per second, in just about six minutes. To safely slow down its descent, the lander had to use a heatshield, a parachute and retro rockets.

“Although we’ve done it before, landing on Mars is hard, and this mission is no different,” said Rob Manning, chief engineer at JPL, during a livestream. “It takes thousands of steps to go from the top of the atmosphere to the surface, and each one of them has to work perfectly to be a successful mission.”

This artist’s concept depicts NASA’s InSight lander after it has deployed its instruments on the Martian surface. Credit: NASA/JPL-Caltech

The InSight lander is currently situated on Elysium Planitia, a plane near the planet’s equator also known by the mission team as the “biggest parking lot on Mars.” Since landing, the robot has taken its first photos, opened its solar panels, and taken preliminary data. It will spend the next few weeks prepping and unpacking the instruments onboard.

The devices will be used to carry out three experiments. The seismometers will listen for ‘marsquakes,’ which can offer clues into the location and composition of Mars’ rocky layers. The thermal probe will reveal how much heat flows out of the planet’s interior and hopefully show how alike (or unalike) Mars is to Earth. And finally, radio transmissions will demonstrate how the planet wobbles on its axis.

In other news, NASA has also chosen a landing site for the next Mars rover, which is expected to launch in 2020. The space agency has announced that the rover will explore and take rock samples from Jezero crater, one of the three locations shortlisted by scientists. The crater is 45 kilometres wide and at one point had been filled with water to a depth of 250 metres. The sediment and carbonate rocks left behind could offers clues on whether Mars had sustained life.

What you might have missed

By analysing radar scans and sediment samples, a team of scientists have discovered a massive crater, hidden underneath more than 900 metres of ice in northwest Greenland. After surveying the site, scientists say it’s likely that a meteorite created the sometime between 3 million and 12,000 years ago.

The depression under Hiawatha Glacier is 31 kilometres wide, big enough to hold the city of Paris. At this size, the crater is one of the top 25 largest craters on Earth; it’s also the first to be found under ice. An impact of this size significant mark on the Earth’s environment. “Such an impact would have been felt hundreds of miles away, would have warmed up that area of Greenland and may have rained rocky debris down on North America and Europe,” said Jason Daley from Smithsonian Magazine.

Links we liked

The EGU Story

This month, we have announced changes to the EGU General Assembly 2019 schedule, which aim to give more time for all presentation types. Check our news announcement for more information. In other news, we have opened applications to the EGU General Assembly 2019 mentoring programme, and are advertising a job opportunity for geoscientists with science communication experience to work at the meeting.

Also this month, we opened the call for applications for EGU Public Engagement Grants, and have announced the creation of the EGU Working Group on Diversity and Equality. Finally, we’ve published a press release on a new study that looked into whether data on seabird behavior could be used to track the ocean’s currents.

And don’t forget! To stay abreast of all the EGU’s events and activities, from highlighting papers published in our open access journals to providing news relating to EGU’s scientific divisions and meetings, including the General Assembly, subscribe to receive our monthly newsletter.

NASA’s InSight mission: detecting ‘earthquakes*’ on the surface of Mars

NASA’s InSight mission: detecting ‘earthquakes*’ on the surface of Mars

In three days’ time, NASA’s InSight Lander is expected to plunge through Mars’ atmosphere before parachuting down to a controlled landing on the flat plains of the Elysium Planitia.

Once the dust has settled, a solar powered robotic arm will painstakingly unload the precious instruments stored onboard onto the planet’s surface, carefully guided by scientists back on Earth.

This is an illustration showing a simulated view of NASA’s InSight about to land on the surface of Mars. (Credit: NASA/JPL-Caltech)

These instruments are designed to penetrate further into Mars’ subterranean secrets than any mission before. While previous Martian landers have monitored the planet’s surface and atmosphere, the goal of InSight, short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport, is to explore Mars’ interior using three specialised tools.

These include a heat probe which will measure the heat flow near to the surface, a radio science instrument which will measure how Mars wobbles on its axis, and a seismometer which will tell us about Mars’ deep interior. Scientists hope this will lead to new information on the formation of the planets in our solar system, perhaps even illuminating more detail on how our own planet came about.

Seismometers detect seismic waves, vibrations that travel through the ground after an event such as fault movement or meteorite impact. The type of wave and the speed at which it travels can provide important details about the material through which it moves. On Earth, a global network of seismometers has provided vital information about the structure of the planet’s core and mantle.

Robert Myhill, a seismologist at the University of Bristol, is part of a large international team of scientists who have been preparing for data returned by InSight’s seismometers (known as SEIS). Until recently, Myhill has been investigating how SEIS will be affected by Mars’ regolith (its shallow soil surface)[1].

Now that SEIS is en route to its Martian home however, Myhill and colleagues are getting ready for the next phase: receiving the data. “We hope to be able to use the waveforms from marsquakes and/or impacts to image the interior structure of the planet for the first time, including the thickness and structure of the crust, and the composition of the mantle and core,” Myhill explains.

“We’ve also been investigating how we can combine the geophysical data returned by InSight with existing geochemical data to tell us about the history of Mars and the continuing evolution of the planet’s deep interior.”

The data they will receive comes from two different types of sensors, a ‘very-broad-band’ (known as ‘VBB’) seismometer and three tiny short-period seismic sensors which are about the size of a Euro coin. The different sensors can detect various types of seismic wave, depending on the size and location of the seismicity.

Animation of InSight deploying it’s seismometer. (Credit: NASA/JPL-Caltech)

Gathering the information needed to achieve the mission’s goals presents numerous challenges. For starters, unlike Earth, which has a network of seismometers that can be used together, InSight will be the only active geophysical station on the Red Planet. Two previous seismometers, mounted on NASA’s Viking Landers in the 1970s, experienced technical faults and design limitations and are no longer in action. As a result, researchers have had to come up with novel ways to gather information from the lone InSight lander [2] [3].

The mission’s designers have also developed new technology to reduce noise and ensure the equipment can operate in Mars’ harsh environment. The seismometer will be mounted on a levelling system close to the Martian surface to minimise tilt and reduce the effect of wind. Once levelled, the lander’s robotic arm will place a wind and thermal shield over the top of the instruments, sheltering the sensitive instruments from extreme temperatures and buffeting by the Martian winds.

Despite the increased protection afforded by the wind and thermal shield, there remain challenges for InSight. “We hope that during the lifetime of the mission, we don’t have a prolonged dust-storm. Although InSight would not be damaged by such an event, it does need solar energy for all its instruments and for data transmission,” said Myhill.

NASA’s InSight mission tests an engineering version of the spacecraft’s robotic arm in a Mars-like environment at NASA’s Jet Propulsion Laboratory. (Credit: NASA/JPL-Caltech)

From 26 November, he and the others involved must wait with bated breath to see their hard work come to fruition. “We should receive the first data from the instrument deck not long after landing, but full deployment of SEIS (including the wind and thermal shield) is not scheduled until early January 2019,” he explains.

“The timing of first results really depends on the level of seismicity, which is currently very poorly known. In fact, determining the rate of seismic energy generation is one of the primary goals of the InSight Mission. But of course, we’re all hoping to see something soon after deployment.”

For the most up to date information on the mission, as well as more details in the lander’s other exciting capabilities see NASA’s InSight website.

*Astute readers of this blog may have noticed the error in the title. There is no such thing as an earthquake on Mars… instead InSight will be monitoring ‘marsquakes’.

By Keri McNamara, freelance science writer

Keri McNamara is a freelance writer with a PhD in Volcanology from the University of Bristol. She is on twitter @KeriAMcNamara and www.kerimcnamara.com.

References

[1]                      https://link.springer.com/article/10.1007/s11214-018-0514-5

[2]                      https://www.sciencedirect.com/science/article/abs/pii/S001910351400582X

[3]                      https://www.sciencedirect.com/science/article/pii/S0031920116300875?via%3Dihub

July GeoRoundUp: the best of the Earth sciences from around the web

July GeoRoundUp: the best of the Earth sciences from around the web

Drawing inspiration from popular stories on our social media channels, as well as unique and quirky research news, this monthly column aims to bring you the best of the Earth and planetary sciences from around the web.

Major stories  

Signs of water 55 million kilometres away

Last week scientists announced that they have found signs of existing water on Mars, offering new hope to the possibility of uncovering life on the Red Planet’s subsurface.  

Radar observations made by the European Space Agency’s Mars Express satellite, suggest that a liquid lake is buried 1.5 kilometres beneath an ice cap situated near the south pole of Mars. Scientists think that this body of water is likely a few metres deep and 20 kilometres across, “nearly three times larger than the island of Manhattan,” reported Scientific American.

A schematic of how scientists used radar to find what they interpret to be liquid water beneath the surface of Mars. (Credit: ESA)

For the last 12 years the Mars Express satellite has been taking measurements of Mars by sending beams of radar pulses into the planet’s immediate interior. As these waves bounce back, the brightness of the reflection gives information on the material lying beneath Mars’ surface.

The researchers involved came across this discovery while analysing three years worth of data collected by the spacecraft.

“The bluer the colors, the brighter the radar reflection from the material it bounced off. The blue triangle outlined in black in the middle is the purported lake,” reported Science News.

Previous observations, made by NASA’s Curiosity rover for example, have found lake beds on the planet’s exterior, signifying that water may have flowed on Mars in the past. However, if this new finding is confirmed, it would be the first discovery of an existing stable body of water, one of the conditions believed to be necessary for life to thrive.

Context map: NASA/Viking; THEMIS background: NASA/JPL-Caltech/Arizona State University; MARSIS data: ESA/NASA/JPL/ASI/Univ. Rome; R. Orosei et al 2018 (distributed via ESA)

“We are not closer to actually detecting life,” said Manish Patel from the Open University to BBC News, “but what this finding does is give us the location of where to look on Mars. It is like a treasure map – except in this case, there will be lots of ‘X’s marking the spots.”

In their study, published in Science last week, the team remarked, “there is no reason to conclude that the presence of subsurface water on Mars is limited to a single location.”

Northern hemisphere feels the heat

In other news, the two words best describing the northern hemisphere this summer could very well “hot” and “dry,” as a series of heat waves have taken hold of several regions across Europe, Asia, North America and northern Africa. Many countries this month, including Japan, Algeria and Canada, have even experienced record-breaking temperatures.

A look at how this year’s heatwave has changed the colour of our vegetation in just one month (Credit: ESA

For some places, above average temperatures and dry conditions have helped fuel devastating wildfires. More than 50 wildfires have swept through Scandinavian forests this summer, many well within the Arctic Circle, causing Sweden to request emergency aid from nearby countries.

Smoke rises from a wildfire in Enskogen. (Credit: Swedish Environmental Protection Agency/Maja Suslin)

A major wildfire also ignited near Athens, Greece this month, resulting in more than 85 death, with dozens still missing. While Greek officials claim that there are “serious indications” that the flames were brought upon by arson, they also note that the region’s climate conditions were extreme.

To many scientists, this onslaught of hot and dry conditions is a taste of what may soon become the norm.  Of course, these conditions (in Europe, for example) are partly due to weather. “The jet stream – the west-to-east winds that play a big role in determining Europe’s weather – has been further north than usual for about two months,” reports the Guardian, leading to sweltering conditions in the UK and much of Europe, while leaving Iceland cool and stormy.  

However, scientists say that heatwaves in the northern hemisphere are very much linked to global warming. “There’s no question human influence on climate is playing a huge role in this heatwave,” said Myles Allen, a climate scientist at the University of Oxford, to the Guardian in the same article.

A recent assessment on the ongoing heat wave in Europe reports that these conditions are more likely to occur due to climate change. “The findings suggest that rising global temperatures have increased the likelihood of such hot temperatures by five times in Denmark, three times in the Netherlands and two times in Ireland,” said Carbon Brief.

What you might have missed

Geologists have given a name to Earth’s most recent chapter: Meghalayan Age. The announcement was made earlier this month when the International Union of Geological Sciences updated the International Chronostratigraphic Chart, which classifies Earth’s geologic time scale. The new update has divided the Holocene Epoch (the current time series which began 11,700 years ago, when the Earth was exiting its last ice age) into three stages: the Greenlandian, the Northgrippian, and then Meghalayan.

The Meghalayan Age represents the time between now and 4,200 years ago, when a mega-drought led to the collapse of many civilisations across the world. The middle phase, Northgrippian (from 8,300 years ago to 4,200 years ago), is marked by an sudden cooling event brought on by massive glacial melt in Canada that affected ocean currents. Finally the oldest phase, Greenlandian, (from 11,700 years ago to 8,300 years ago) is marked by the end of the last ice age.

The recent update has created some unrest in the geosciences community. “There is still an active debate about assigning a new geologic slice of time to reflect specifically the influence of humans on the planet,” reported BBC News. Some scientists say that the new divisions conflict with the current work being done on proposing a new epoch classification, famously called the ‘Anthropocene,’ which would be marked by the beginning on significant human impact on Earth’s geology and ecosystems.

Links we liked

The EGU story

This month we released not one but two press releases from research published in our open access journals. The findings from both studies have important societal implications. Take a look at them below.

New study: oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”

The Baltic Sea is home to some of the world’s largest dead zones, areas of oxygen-starved waters where most marine animals can’t survive. But while parts of this sea have long suffered from low oxygen levels, a new study by a team in Finland and Germany shows that oxygen loss in coastal areas over the past century is unprecedented in the last 1500 years. The research was published in the European Geosciences Union journal Biogeosciences.

New study puts a figure on sea-level rise following Antarctic ice shelves’ collapse

An international team of scientists has shown how much sea level would rise if Larsen C and George VI, two Antarctic ice shelves at risk of collapse, were to break up. While Larsen C has received much attention due to the break-away of a trillion-tonne iceberg from it last summer, its collapse would contribute only a few millimetres to sea-level rise. The break-up of the smaller George VI Ice Shelf would have a much larger impact. The research was published in the European Geosciences Union journal The Cryosphere.

And don’t forget! To stay abreast of all the EGU’s events and activities, from highlighting papers published in our open access journals to providing news relating to EGU’s scientific divisions and meetings, including the General Assembly, subscribe to receive our monthly newsletter.

Mars Rocks – introducing a citizen science project

Mars Rocks – introducing a citizen science project

GeoLog followers will remember our previous report on Citizen Geoscience: the exciting possibilities it presents for the acquisition of data, whilst cautioning against the exploitation of volunteered labour. This blog presents a Citizen Science platform that goes beyond data collection to analysis, specifically for geological changes in remote sensing imagery of Mars. Jessica Wardlaw, a Postdoctoral Research Associate in Web GIS, at the Nottingham Geospatial Institute, introduces ‘iMars’ and explains 1) its scientific mission and 2) why imagery analysis is especially suitable for a crowd sourcing approach, so that you might consider where and how to apply it to your project.

Imagine, just for a moment, that the Mars Geological Survey invited you to an interview for the position of Scientist in Charge. Why and how would you reconstruct the geological past for a remote planet such as Mars? Where would you start? Earth is the “Goldilocks” planet, not only for human habitation but for geologists too, who can sample and test rock to understand the evolution of the Earth’s surface on which to base well-established theories such as plate tectonics. To understand the geological past and processes of remote planets, however, requires different approaches.

Planetary scientists investigate the climate and atmosphere, and the geological terrain, of planets to further understanding of our own place in the solar system. Mars provides a scintillating snapshot of early Earth; whilst some scientists contend that plate tectonics has historically happened on Mars, 70% of its surface dates from the moment it formed and provides a platform from which to view Earth in its infancy. In fact, despite our limited knowledge of Mars, it has already informed our understanding of Earth, inspiring James Lovelock’s Gaia theory. Imminent missions to the red planet are also already exploiting geological information to inform landing sites and routes of roving vehicles on Mars. The more information scientists have, the more likely missions are to land in suitable locations to successfully pursue scientific goals, such as understanding the ability of the Martian environment to support life and water, both now and in the past, which could further theories on the origins of the solar system, life on Earth, and Earth’s destiny.

Many will remember this summer for the astonishing images that arrived from Pluto, but 50 years ago, almost to the day, people celebrated the first successful fly-by mission to Mars. Mariner 4 took 21 images from a distance 6,000 miles, which, after the initial excitement, disappointingly revealed that Mars had a Moon-like cratered surface, and led to a long-held misconception of a dead, red planet. It was in 1976 that two Viking landers touched down on the red soil for the first time, paving the way for further Martian missions, with the first mission of the European Space Agency’s ExoMars programme launching next year.

The first Mars photograph and our first close-up of another planet. A representation of digital data radioed by the Mariner 4 spacecraft on 15th July 1965. (Credit: NASA/JPL-Caltech/Dan Goods)

The first Mars photograph and our first close-up of another planet. A representation of digital data radioed by the Mariner 4 spacecraft on 15th July 1965. (Credit: NASA/JPL-Caltech/Dan Goods)

Scientists analyse the size and density of craters from meteorite impacts to age the surface. The theory goes that smaller meteorites collide with a planet much more frequently than larger ones, and older surfaces have more craters because they have been exposed for longer. Advances in imaging technology since then now provide scientists with greater granularity than ever before and glimpses of other geologic features, recognisable from the surface of the Earth; sand dunes, dust devils, debris avalanches, gullies, canyons all appear and tell us about the planet’s climatic processes. The Planet Four website is just one example.

The images taken of Mars over the last forty years reveal changes on the surface that indicate invaluable information that help us to understand the climate and geology of the planet. Changes are visible in imagery over a variety of timescales, from rapidly-moving dust devils (much bigger that the one that once trapped me in Death Valley), seasonal fluctuations of the polar ice caps and recurring slope lineae (recently reported to indicate contemporary water activity) polar ice caps and the snail-slow shaping of sand dunes.

Three images of the same location taken at different times over one Martian year show how the seasonal fluctuation of the polar cap of condensed carbon dioxide (dry ice), between its solid and gaseous state, destabilises a Martian dune at high altitude to cause sand avalanches and ripple changes. (Credit: NASA/JPL/University of Arizona)

Three images of the same location taken at different times over one Martian year show how the seasonal fluctuation of the polar cap of condensed carbon dioxide (dry ice), between its solid and gaseous state, destabilises a Martian dune at high altitude to cause sand avalanches and ripple changes. (Credit: NASA/JPL/University of Arizona)

The quality and coverage of these images, however, varies greatly due to atmospheric conditions and tilt of the camera amongst other reasons. To create a consistent album of imagery, that we can confidently compare and use to identify geological changes in the images, requires considerable computational work. Images from across as much of the Martian surface as possible must be processed to remove those of poor quality and correct for different coordinate systems (co-registration) and terrain (ortho-rectification).

The iMars project is applying the latest Big Data mining techniques to over 400,000 images, so that they can be used to compute and classify changes in geological features. On a Citizen Science platform, Mars in Motion, volunteers will define the nature and scale of changes in surface features from ortho-rectified and co-registered images to a much greater detail. Human performance is inherently variable in ways we cannot fully control, either, in the same way that we can control the performance of an algorithm. Although we are investigating this too, this would require another blog post! For now I will describe the reasons why we are using a crowd-sourcing approach for this project so that you might consider how you could apply it to your research.

First of all, humans have evolved over millions of years to identify subtle variations in visual patterns to a more sophisticated level than computers currently can. Computers can execute repetitive tasks and store an infinite amount of information with far less impact on their performance than humans; the human mind, however, has proved to be too flexible and creative for computers to fully replicate, with the success of Citizen Science projects such as Galaxy Zoo, which has so far resulted in 48 academic publications. The slow seasonal shift of sand dunes on Mars, for example, would require a computer algorithm of inordinate intelligence to identify, as previous attempts to automatically detect impact craters, valley networks and sand dunes in images of Mars have found. Recent research has resulted in some very sophisticated algorithms for image analysis, but detection of changes in such a range of geological features over the range of spatial and temporal scales that we are looking to do is computationally complex and expensive. Without sending somebody to Mars, how do we know whether the computer is correct? Machine learning algorithms can only calculate what you ask them to, so are ill-equipped to make the sort of serendipitous discoveries of the unknown required in the detection of change. Volunteers in the Mars in Motion project will seek differences (Figure 4), rather than similarities, between the images and it is inherently challenging to program a computer to find something that you don’t even know to look for.

Mars in Motion: Spot the difference...on the surface of Mars!

Mars in Motion: Spot the difference…on the surface of Mars!

Secondly, we have so much data that scientists could not possibly do all of this themselves! In many areas of science and humanities, but especially in Earth and Planetary observation, Big Data capture is growing at an astronomical rate, far faster than resources and techniques for its analysis can keep up so that we are increasingly unable to handle it. This is where geoscientists have started to join the trend for recruiting volunteers to analyse imagery with some success; through large crowd-sourcing image analysis projects, like TomNod, citizens continually contribute interpretation of images for social and scientific purposes. The number of volunteers, however, is finite and the increase in data places more and more demand upon their time. Researchers using the Citizen Science approach must now carefully consider how their projects can utilise volunteers’ time effectively, efficiently and ethically.

Third and finally, a crowd-sourcing approach exposes the public to improvements in imaging technology and brings the dynamic nature of the Martian surface to life. This can only improve the chances of space exploration receiving further funding and entering classrooms through the way it combines many areas of Science, Technology, Engineering and Mathematics. Serendipitously, the engagement of the public also increases the number of pairs of eyes that analyse the images and, as such, the confidence with which scientists can use their classifications. As we collect more and more data, image analysis will necessarily require collaboration between humans and computers, as well as between volunteers and researchers, to manage it.

I hope this post gives you an insight into how we are applying the Citizen Science to consider how it might help your research too. There is actually no better time to try setting up a Citizen Science project with the launch of the Zooniverse project builder, which makes it easier than ever before to build your own project.

By Jessica Wardlaw, researcher at the University of Nottingham

The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under the iMars grant agreement no. 607379.

Visit www.i-mars.eu and follow @JessWardlaw for updates on iMars and Mars in Motion.