These are the Scisco media science dispatches for the second week in July 2018, including Mars’ ‘ghost’ dunes, CERN’s technology leads to colour X-ray breakthrough which may revolutionise disease identification and the further development of ammonia as a renewable, carbon-free fuel.
Mars’ ‘Ghost’ Dunes could harbour evidence of ancient life
It seems like every time I come to write a science dispatch there is another report or press release that suggests the possibility of discovering life in the solar system. Such a preponderance of stories simply exemplifies what an exciting stage of space-exploration we are currently at.
The latest development involves the discovery of hundreds of ancient crescent-shaped depressions on Mars’ surface by the Mars Reconnaissance Orbiter. These depressions, located in the planet’s southern hemisphere at an ancient impact crater named Helios, are likely all that remains of a series of massive sand dunes that once existed on the red planet’s surface.
The dunes were likely preserved when lava or other sediments flowed through and around them resulting in them being partially buried. This buried section then hardened and was exposed when harsh conditions and wind eroded the surface sand.
A research team from the American Geophysical Union has suggested in a statement released to the press, that these dunes, which stood at between 40-75 meters before they were buried, may have been high enough to protect simple life from harsh solar and cosmic radiation. Thus signs of ancient life may well be preserved within the ridges.
“We know that dunes on Earth can support life, and dunes on Earth are very similar to dunes on Mars,” said Mackenzie Day, a planetary geomorphologist from the University of Washington in Seattle and lead author of the study published in the Journal of Geophysical Research: Planets.
“One problem that Mars has that Earth doesn’t is the surface radiation,” Day continued, “If you are inside a dune, or at the bottom of a dune, and you are microbial life, the dune is protecting you from a lot of that radiation. There is probably nothing living there now. But if there ever was anything on Mars, this is a better place than average to look.”
Ghost dunes of this type aren’t unique to Mars. Similar dunes were discovered on Earth in the snake-river plain Idaho for example. Dunes of this type are known as Barchan dunes. Crescent-shaped features which occur on flat surfaces with little sand, in areas where the wind blows mostly from one direction.
The image below taken from Google Earth shows Barchan dunes found in Egypt and gives an idea what the recently discovered ‘ghost’ dunes of Mars would have looked like before they were buried.
Aside from possibly giving clues as to ancient life on Mars, the dunes give good indications of how winds once moved across the surface of the planet and how sediments were pushed across its plains.
“The fact that the wind was different tells us that the environmental conditions on Mars aren’t static over long timescales, they have changed over the past couple billion years, something we need to know to interpret the geology on Mars,” Day said.
CERN technology leads to first 3D colour X-rays
A father and son team, Professors Phil and Anthony Butler from Canterbury and Otago Universities working for a New Zealand company have used technology pioneered by CERN to develop the first colour 3D X-ray imaging device.
The device, based on the Medipix3 technology developed at CERN, was used to scan a human body for the first time and could be a boon for the medical industry. The advantage it conveys is the ability to scan the body and identify different tissues and their composition, something that will be a massive bonus in the identification of cancers for example.
Medipix was designed to register and count individual particles hitting pixels whilst its electronic shutter is open, very much like a camera operates. The original usage of the family of Medipix chips was to track particle interactions at the Large Hadron Collider, but the ability of the chips to produce high-definition, high-resolution images makes it incredibly useful for the medical industry.
Professor Phil Butler states “this technology sets the machine apart diagnostically because its small pixels and accurate energy resolution mean that this new imaging tool is able to get images that no other imaging tool can achieve.”
MARS Bioimaging Ltd, which is commercialising the 3D scanner, couples the spectroscopic information generated by the Medipix3 enabled detector with powerful algorithms to generate 3D images. The colours represent different energy levels of the X-ray photons as recorded by the detector, enabling the identification of different components of body parts such as fat, water, calcium, and possible disease markers.
Thus far, the researchers at MARS and the universities associated with it, have been using the scanner to examine cancer, bone and joint health, and various vascular diseases which can lead to heart attacks and strokes. “In all of these studies, promising early results suggest that when spectral imaging is routinely used in clinics it will enable more accurate diagnosis and personalisation of treatment,” Professor Anthony Butler says.
The research was enabled by CERN’s ‘Knowledge Transfer Group’ which has a history of helping other organisations take advances developed by CERN and apply them to other areas, especially the medical industry. Aurélie Pezous, CERN Knowledge Transfer Officer states: “It is always satisfying to see our work leveraging benefits for patients around the world. Real-life applications such as this one fuel our efforts to reach even further.”
Clinical trials of the Medipix3 will now begin in New Zealand involving rheumatology patients, hopefully leading to the wider application of the scanner and perhaps a revolution in disease identification.
Is a carbon-free ammonia fuel cell the future of renewable energy?
Barren areas of Australia could be the key to exploiting the natural energy of the sun with a little man-made assistance, Douglas MacFarlane, a chemist at Monash University in suburban Melbourne believes.
More sunlight strikes the arid landscape of Australia than any other area of the Earth’s surface, and filling this landscape with solar panels could represent renewable energy potential of 25,000 gigawatts, one of the highest in the world and about four times the planet’s installed electricity production capacity.
The problem with this is that with a relatively small population and no way to export or store this energy it will simply never be used. That is where MacFarlane comes in.
The chemist has spent the past four years developing a carbon-free fuel cell, based on ammonia. Whereas traditional fuel cell store energy in created chemical bonds and use this to generate electricity, MacFarlane’s cell works almost in reverse. The small, stainless steel device uses supplied electricity, nitrogen gas and water to produce ammonia. This would allow companies to produce ammonia, primarily used for fertilizer, in greater amounts and in much more environmentally friendly ways. But the device’s applications do not end there.
By using electricity generated by renewable sources the cell creates a liquid fuel which can be stored and supplied across the world at which point it can be converted back into electricity or hydrogen gas to power fuel cell based engines. “Liquid ammonia is liquid energy,” MacFarlane says, adding “It’s the sustainable technology we need.”
Ammonia, one nitrogen atom bonded to three hydrogen atoms has an energy density by volume double that of hydrogen, which is currently the most likely candidate for a ‘green fuel’. “You can store it [ammonia], ship it, burn it, and convert it back into hydrogen and nitrogen,” Tim Hughes, an energy storage researcher with manufacturing giant Siemens in Oxford, U.K tells Science. “In many ways, it’s ideal.”
Economically speaking Australia, currently heavily reliant on the supply of fossil fuels, is gearing itself up for a potential ‘ammonia economy’. “In Australia’s states, politicians see renewable ammonia as a potential source of local jobs and tax revenues,” says Brett Cooper, chairman of Renewable Hydrogen, a renewable fuels consulting firm in Sydney. “In Queensland, officials are discussing creating an ammonia export terminal in the port city of Gladstone, already a hub for shipping liquefied natural gas to Asia. In February, the state of South Australia awarded AU$12 million in grants and loans to a renewable ammonia project. And last year, an international consortium announced plans to build a US$10 billion combined wind and solar plant known as the Asian Renewable Energy Hub in Western Australia state.” Science also reports.