The two projects, still in their concept phase, are the Lunar Flashlight and the Resource Prospector Mission, both with a launch date between 2017-2018. The first one, the Lunar Flashlight, is what is called a CubeSat mission, meaning the body of the spacecraft is tiny and will expand once deployed in space. In this case, the probe will be sustained, and propelled toward the moon, by a 860-square-foot (80 square meters) solar sail. It will not land, but only orbit our satellite, mapping easily accessible water deposits. For the launch itself, it will most likely piggy-back on the new Orion’s NASA Rocket.
“If you’re going to have humans on the moon and you need water for drinking, breathing, rocket fuel, anything you want, it’s much, much cheaper to live off the land than it is to bring everything with you.” (Barbara Cohen, NASA’s Marshall Space Flight Center, Lunar Flashlight’s project principal investigator).
The existence of water on the lunar surface is not a recent discovery. Since the 1960s NASA had suspected the presence of frozen water in the dark craters at the Moon’s poles. Early lunar missions have provided some preliminary clues, but the confirmation has come from the Lunar Reconnaissance Orbiter (LRO), which has spotted areas near the south pole where water is likely to exist. The key to this discovery? Hydrogen. LRO is equipped with a Lunar Exploration Neutron Detector, or LEND, that measures how much hydrogen is trapped within the lunar soil.
“How is the water ice distributed in the soil? That’s really what Resource Prospector is fundamentally about, is identifying, locating the ‘ore’ and understanding how to excavate it — how to get at it — and what does that cost in terms of energy.” (Tony Colaprete, NASA Ames RPM project scientist)
While it is certainly the nearest, the Moon is not the only repository of water in space. Since 1969, when the existence of water outside Earth has been announced, a few other celestial bodies have been identified as potential sources, from the Martian soil to Enceladus’ plumes, until the recent, startling discovery of a giant vapour cloud of water around a black hole 12 billion light years away from the Solar System.
But the most important implications of the two NASA missions are definitively for the human adventure to Mars, which is increasingly under consideration. And this is where NASA’s second project, the Resource Prospector Mission (RPM), comes into play. The RPM plans to land onto the lunar surface and map concentrations of hydrogen. Also, it will extract oxygen from the lunar rocks with a technique called in-situ resource utilization (ISRU), and combine it with hydrogen carried onboard to create water. The ISRU technique – that initially will be devoted to high-mass, low-information materials, such as propellant and shielding, but that can later be expanded in 3D printed components – will save many billions of dollars in space budget. According to many scientists, it will represent the way humans will eventually go to Mars. Moreover, engineers can even design an ISRU strategy that takes materials for the Mars trip from lunar soil, thus reducing the amount of mass launched from Earth (and costs).
“I will go so far as to say that a human Mars mission is inconceivable without incorporating ISRU in some form, most likely as a source of propellant but also for other potential uses (e.g., shielding, oxygen and water). A Mars mission conducted in the Apollo mode (everything launched from Earth) is simply not possible, fiscally or politically. A national security imperative during Apollo allowed us to bludgeon technical problems to death with money. We no longer live in that world. Space programs must be affordable, which means that we cannot opt for the “easiest” or most familiar way to do something – we must be clever, frugal and use what is available.” (Paul D. Spudis, Lunar and Planetary Institute in Houston)
It really seems that, in order to continue with space exploration, a return to the Moon is going to be a compulsory step.
Photo Credit: Space.com