Establishing a human settlement on Mars has been the fevered dream of space agencies for some time. Long before NASA announced its “Journey to Mars” – a plan that outlined the steps that need to be taken to mount a manned mission by the 2030s – the agency’s was planning how a crewed mission could lead to the establishing of stations on the planet’s surface. And it seems that in the coming decades, this could finally become a reality.
But when it comes to establishing a permanent colony – another point of interest when it comes to Mars missions – the coming decades might be a bit too soon. Such was the message during a recent colloquium hosted by NASA’s Future In-Space Operations (FISO) working group. Titled “Selecting a Landing Site for Humans on Mars”, this presentation set out the goals for NASA’s manned mission in the coming decades.
Picking a landing site on Mars is a complex process. There’s the need to balance scientific return with the capabilities of whatever vehicle you’re sending out there. And given each mission costs millions (sometimes billions) of dollars — and you only get one shot at landing — you can bet mission planners are extra-cautious about choosing the right location.
A recent paper in Eos details just how difficult it is to choose where to put down a rover, with reference to the upcoming European ExoMars mission that will launch in 2018.
In March, scientists came together to select the first candidate landing sites and came up with four finalist locations. The goal of ExoMars is to look for evidence of life (whether past or present) and one of its defining features is a 2-meter (6.6-foot) drill that will be able to bore below the surface, something that the NASA Curiosity rover does not possess.
“Among the highest-priority sites are those with subaqueous sediments or hydrothermal deposits,” reads the paper, which was written by Bradley Thomson and Farouk El-Baz (both of Boston University). Of note, El-Baz was heavily involved in landing site selection for the Apollo missions.
“For example,” the paper continues, “some of the clearest morphological indicators of past aqueous activity are channel deposits indicative of past fluvial activity or the terminal fan, or delta deposits present within basins.”
But no landing site selection is perfect. The scientists note that Curiosity, for all of its successes, seems unlikely to achieve its primary science objectives in its two-year mission because the commissioning phase took a while, and the rover moves relatively slowly.
What could change the area of the landing could be using different types of entry, descent and landing technologies, the authors add. If the parachute opened depending on how far the spacecraft was from the ground — instead of how fast it was going — this could make the landing ellipse smaller.
This could place the rover “closer to targets of interest that are too rough for a direct landing and reducing necessary traverse distances,” the paper says.