The Lunar Flashlight is exactly what it sounds like — a spacecraft that will shine infrared light on some of the permanently shadowed parts of the Moon in an effort to find water — and NASA is looking to launch next month.
The brief-case-sized satellite will scan the Moon’s south pole, where there could be reservoirs of ice water located inside permanently shadowed regions. Lunar Flashlight could locate these reservoirs, which are typically at the bottom of craters, by beaming down near-infrared lasers using an instrument called a four-laser reflectometer. Infrared wavelengths are absorbed by water, so any evidence of the stuff would be reflected back to the satellite from lunar rocks and soil. The method could allow NASA to not only find the reservoirs but potentially figure out how large they are since more absorption could indicate more water.
“This launch will put the satellite on a trajectory that will take about three months to reach its science orbit,” said John Baker in a NASA press release. Baker is the Lunar Flashlight mission’s project manager at NASA’s Jet Propulsion Laboratory in California. “Then Lunar Flashlight will try to find water ice on the surface of the Moon in places that nobody else has been able to look.”
Lunar Flashlight will be using a new kind of propellant developed by the Air Force Research Laboratory called a “monopropellant” since it does not need a separate oxidizer to burn, instead relying on a catalyst. NASA argues that this monopropellant is safer to transport than something like hydrazine, which is more commonly used.
Since the propellant will be limited by the small footprint of the satellite, Lunar Flashlight will be using the more fuel-efficient near-rectilinear halo orbit, much like the upcoming Lunar Gateway space station. Mission navigators will guide Lunar Flashlight past the Moon, where gravity from the Earth and Sun will pull it back, allowing the satellite to settle into a sweeping, oval-shaped orbit. This will be only the second NASA mission so far to rely on this type of orbit, following CAPSTONE. At its closest point to the Moon, Lunar Flashlight will skirt a mere 15 kilometres above the surface.
Finding ice water to turn into drinking water, fuel, or even breathable oxygen is a crucial first step in setting up long-term settlements for astronauts on the Moon. Lunar Flashlight is set to launch aboard a SpaceX Falcon 9 rocket in mid-November and is a part of a continued effort by NASA to learn more about the Moon before the Artemis program becomes a full-fledged effort to return humans to our natural satellite.