On December 11, 2022, NASA’s Lunar Flashlight mission successfully launched to begin a four-month trip to the moon. Once there, the tiny satellite, or SmallSat, will test a number of novel technologies in an effort to find buried surface ice near the lunar South Pole. The NASA mission is describing its brand-new “green” propulsion technology and formulating a revised roadmap for the briefcase-sized satellite’s lunar voyage.
The mission operations team has found that three of the SmallSat’s four thrusters are underperforming, despite the fact that the SmallSat is essentially healthy and in contact with NASA’s Deep Space Network.
The mission crew is attempting to identify the problem and provide potential remedies after seeing the lower thrust for the first time three days after launch. Lunar Flashlight’s propulsion system has worked for brief pulses that have lasted up to a few seconds during its flight. Based on tests conducted on the ground, the team hypothesises that clogs in the fuel lines may be preventing enough propellant from reaching the thrusters to explain the underperformance.
The team hopes to remove any possible blockages in the thruster fuel line while performing trajectory correction operations that will keep the SmallSat on schedule to achieve its intended orbit around the moon. They want to soon use the thrusters for considerably longer periods of time. The mission team is developing backup plans to carry out those manoeuvres using the propulsion system with its present reduced-thrust capacity in the event that the propulsion system cannot be brought back to full functionality. To reach lunar orbit in around four months, Lunar Flashlight will need daily trajectory correction procedures beginning in early February.
A novel laser reflectometer made with four near-infrared lasers will be used by the briefcase-sized SmallSat to beam light into the perpetually darkened craters at the lunar South Pole in order to identify surface ice as it swoops low over the moon’s surface. Lunar Flashlight will use an energy-efficient near-rectilinear halo orbit, bringing it within 9 miles (15 km) of the lunar South Pole and 43,000 miles (70,000 km) distant at its furthest point, to accomplish this aim with the small amount of propellant it is constructed to carry.
The NASA Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment (CAPSTONE) mission, which launched in June 2022 to a different near-rectilinear halo orbit, the same orbit that is planned for Gateway, is the only other spacecraft to have used this sort of orbit. While CAPSTONE also had challenges on its mission to the moon, several of the NASA teams who assisted the SmallSat in achieving its intended orbit are now offering their assistance in resolving Lunar Flashlight’s thruster troubles.
Lunar Flashlight, operated by NASA’s Jet Propulsion Laboratory in Southern California, is the first interplanetary spacecraft to utilise a novel “green” propellant known as Advanced Spacecraft Energetic Non-Toxic (ASCENT), which is less hazardous to transport and store than conventional propellants like hydrazine. To showcase this technology for potential application in the future is one of the mission’s main objectives. Using a prior NASA technology demonstration trip in Earth orbit, the propellant was successfully tested.
Other components of Lunar Flashlight are operating effectively, such as the Sphinx flight computer, which has never flown before and was created by JPL as a low-power, radiation-tolerant SmallSat alternative. The updated Iris radio on Lunar Flashlight, which is used to connect with the Deep Space Network, is operating as intended and has a new precision navigation function that will be used by tiny spacecraft in the future to rendezvous and land on other solar system worlds. Before the expedition reaches lunar orbit, more novel and ground-breaking systems, such as the laser reflectometer, will be tested.
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