Mars has long held captive the imaginations of people across the globe. Occasionally visible with the naked eye, the distant Red Planet has always appeared at the very edge of what might one day be possible. As Mars exploration projects ramp up, the planet seems to edge closer within our grasp, and we can’t get enough of it. The Red Planet has been the focus of human imagination for centuries. The fourth planet away from the Sun, and the second smallest planet in our solar system, Mars’ surface conditions and the presence of water arguably make it the most hospitable planet Is nearby after Earth. Long-held concerns about the future habitability of Earth have increased focus on off-world settlements in recent years, with both the Moon and Mars being primary targets. Private and publication organisations alike have been investing heavily in studies and developing there technologies for potential future colonization efforts, including NASA, Roscosmos, the Chinese National Space Administration, the European Space Agency (ESA), Lockheed Martin, SpaceX, Mars One and Boeing. It’s not just Mars’ proximity that makes it a potential candidate for humanity’s first off-world base. Indeed, life Mars and Earth have certain similarities that render the Red Planet a curious prospect for settlement: • The Martian day is 24 hours, 39 minutes and 35.244 seconds. In contrast, the Moon day is almost 30 Earth days long. on • With an axial tilt of 25.19°, similar to Earth’s 23.44°, Mars has seasons much like Earth, although each is about twice as long, as the Martian year is around 1.88 Earth years. • Recent discoveries have confirmed the presence of water in ice form on Mars. The differences between Mars and Earth, however, are numerous. Each would need compensating for in Mars? order to establish a successful human settlement. • Mars’ gravity measures 38 percent of Earth’s; while microgravity has been found to cause adverse health effects including muscle loss and bone mineralization, it is not yet known whether Mars’ gravity will have the same effects. Further studies are required. • The Martian atmosphere is 95 percent carbon dioxide, 3 percent nitrogen, 1.6 percent argon, and traces of other gases, including oxygen, totalling less than 0.4 percent. Earth’s atmosphere, in contrast, is 78 percent nitrogen, 21 percent oxygen, and 1 percent other gases. • The lack of magnetosphere in the Martian atmosphere means that solar particle events and cosmic rays easily reach the surface, while the thin atmosphere does not keep out UV rays. • Martian atmospheric pressure is below the Armstrong limit where humans can survive without pressure suits. • Average surface temperatures of -87 to -5°C are Mars from horizon to horizon much lower than are found on Earth. Indeed, Mars Image: ESA/DLR/FU Berlin has an eccentric orbit; thus, temperature and 12 NewSpace International - September/October 2018 www.newspaceinternational.com #MARS #SETTLEMENT #ESA #MARSEXPRESS solar constant variations are much higher than (MARSIS) to confirm the presence of liquid water on Earth. Mars. • Mars is 52 percent farther away from the Sun than The ground-penetrating radar investigation has Earth, and the amount of solar energy reaching shown that the south polar region of Mars is made of the Martian surface is just 43.3 percent of what many layers of ice and dust down to a depth of about reaches Earth. 1.5km in the 200km-wide area analysed in the study. A particularly bright radar reflection underneath the Scientists and engineers across the globe would have layered deposits is identified within a 20km-wide zone. us believe that these differences are just challenges to Analysing the properties of the reflected radar signals be overcome with technology; habitats can, in theory, and considering the composition of the layered deposits be created to support human life even on Mars, while and expected temperature profile below the surface, advanced communications solutions can help solve the the scientists interpret the bright feature as an interface psychological challenges of living so far from Earth. between the ice and a stable body of liquid water, which Companies and organisations the world over are duly could be laden with salty, saturated sediments. For getting in on the action – the race to Mars is on! MARSIS to be able to detect such a patch of water, it would need to be at least several tens of centimetres Mars Express celebrates 15 years of exploration thick. The ESA’s Mars Express programme is celebrating its “This subsurface anomaly on Mars has radar fifteenth year of operations this year. Launched from properties matching water or water-rich sediments,” said Kazakhstan in 2003, the Mars Express Orbiter has Roberto Orosei, Principal Investigator of the MARSIS produced global maps tracing the planet’s geological experiment. “This is just one small study area; it is an activity, water, volcanism and minerals, studied canyons, exciting prospect to think there could be more of these polar ice caps, impact craters and volcanoes, probed underground pockets of water elsewhere, yet to be the surface with radar, and explored the Martian discovered.” atmosphere. A recent upgrade to Mars Express software “We’d seen hints of interesting subsurface features has extended the lifetime of the mission, possibly for years, but we couldn’t reproduce the result from orbit through to the mid-2020s. to orbit, because the sampling rates and resolution of In July, a new study based on ten years of data from our data was previously too low,” added Andrea the radar instrument on Mars Express indicated that the Cicchetti, MARSIS Operations Manager. “We had to complex Martian atmosphere does in fact behave as a come up with a new operating mode to bypass some single, interconnected system, with processes occurring onboard processing and trigger a higher sampling rate at low and mid-levels significantly affecting those seen and thus improve the resolution of the footprint of our higher up. Mars’ atmosphere continuously leaks into dataset: Now we see things that simply were not space; the planet has lost the majority of its denser and possible before.” wetter atmosphere, causing it to evolve into the dry planet we see today. Understanding the atmosphere is ExoMars breaks ground vital for future missions to Mars, particularly for future The ESA and Russian Space Agency Roscosmos have settlement possibilities. The new findings could also joined forces to expand human understanding of potentially help scientists to understand how Mars’ Mars. ExoMars (Exobiology on Mars) is a two-part atmosphere evolves over time – not only with respect astrobiology project to search for evidence of life on to external disturbances such as space weather and the Mars. The first part is a Trace Gas Orbiter (TGO) research activity of the Sun, but also with respect to Mars’ own and communications satellite which was launched to strong internal variability and surface processes. Mars’ orbit in 2016. The TGO has a planned lifetime of “The lower and middle levels of Mars’ atmosphere seven years in orbit, where it will study trace gases, appear to be coupled to the upper levels: There’s a clear primarily methane, in the Martian atmosphere, that could link between them throughout the Martian year,” said be evidence of biological activity. It will also act as the Lead Author Beatriz Sánchez-Cano of the University of communications link between the planned 2020 Leicester. ”We found this link by tracking the amount of ExoMars rover, and Earth. The second part of the project electrons in the upper atmosphere – a property that has is a land rover, will be launched in 2020, and is expected been measured by the MARSIS radar for over a decade to operate through 2022. across different seasons, areas of Mars, times of day, In April, the ExoMars TGO returned its first images of and more – and correlating it with the atmospheric Mars from its orbit above the planet. The TGO’s Colour parameters measured by other instruments on Mars and Stereo Surface Imaging System (CaSSIS) captured Express.” a 40 km-long segment of Korolev Crater located high in Later in the same month, radar data collected by the the northern hemisphere. The orbiter’s camera is one of Mars Express pointed to a pond of liquid water buried four instruments on the TGO, which also hosts two under layers of ice and dust in the south polar region of spectrometer suites and a neutron detector. The Mars. We’ve been aware for some time that liquid water spectrometers began their science mission on 21 April used to be prevalent on Mars’ surface, and that ice can with the TGO making its first tests of the atmosphere, be found on the surface even today. Early results from looking at how molecules in the atmosphere absorb the Mars Express showed that ice exists at the planet’s sunlight: Each has a unique fingerprint that reveals its poles, buried in layers by dust, and the presence of liquid chemical composition. A long period of data collection water at the base of the polar ice caps has long been will be required, as the trace gases comprise less than suspected. Scientists have now developed new one percent of the volume of the planet’s atmosphere. techniques for utilising the Mars Advanced Radar for The camera will eventually help characterise features Subsurface and Ionosphere Sounding instrument on the surface that may be related to trace gas sources. www.newspaceinternational.com NewSpace International - September/October 2018 13 #MARS #LOCKHEEDMARTIN #EXOMARS “We were really pleased to see how good this picture tests. was given the lighting conditions,” said Antoine Another test model will soon start an eight month- Pommerol, a member of the CaSSIS science team long campaign focusing on the rover’s movements and working on the calibration of the data.