Japan’s first attempt at a lunar landing appears to have ended with the loss of the vehicle – once again proving that, for all its successes, spaceflight is nowhere close to being a certainty.
Launched by a SpaceX Falcon 9 in December 11th, 2023 on a low-energy ballistic trajectory that carried it 1.4 million km from Earth before starting on its return, with the Moon getting in the way to allow the vehicle enter an extended elliptical orbit on March 20th, 2023. Over the course of the next several weeks that orbit was circularised, allowing the vehicle to attempt a landing on April 25th.
Essentially a private mission – the lander was built by Tokyo-based ispace – the craft was carrying a set of private and government-sponsored payloads. Among them was Rashid, a small lunar rover developed by the Mohammed bin Rashid Space Centre in the United Arab Emirates, and a “transformable lunar robot” the size of a baseball from Japan’s space agency JAXA. Other payloads include cameras and technology demonstrations.
The landing was streamed live and appeared to initially go well, the HAKUTO-R M1 vehicle having survived its extended trip to the Moon with only minor issues, all of which ispace were able to rectify. However, during the final part of the lander’s decent – whilst it was still some 80 metres above the lunar surface, close to Atlas Crater and descending at a rate of 48 km/h, the telemetry readings for the lander appeared to switch from live data to a simulation, with no subsequent confirmation of a safe landing or any further receipt of telemetry.
ispace initially acknowledged the potential vehicle loss 25 minutes after the planned landing. It came after repeated attempts at communication had failed; six hours after that, the company issued a statement confirming they believed the vehicle had been lost.
During the lander’s final approach to the surface [the] estimated remaining propellant reached at the lower threshold and shortly afterward the descent speed rapidly increased. Based on this, it has been determined that there is a high probability that the lander eventually made a hard landing on the Moon’s surface … it has been determined that Success 9 of the Mission 1 Milestones, successfully landing on the Moon and establishing communications, is no longer achievable.
– ispace announcement on the loss of the HAKUTO-R M1 lander
Despite the loss, Takeshi Hakamada, founder and chief executive of ispace, believes the mission yielded valuable data from both the development and flight of the M1 lander. This, he said would be fed into the company’s next lander mission – M2 – which is targeting a late 2024 launch. It will carry a set of customer payloads as well as a “micro rover” that ispace developed. That rover will collect a regolith sample that will be transferred to NASA under a 2020 contract awarded to ispace’s European subsidiary.
Ingenuity Snaps Perseverance
Voyager 2 Gets Extended Mission Life
NASA engineers have developed a means to extend the science lifespan of their venerable Voyager 2 space probe beyond its already impressive 45 years – and could do the same for the Voyager 1 craft.
The twin Voyager programme vehicles, launched in August and September 1977 respectively, are the only human-made spacecraft to reach interstellar space. Together, they are helping scientists understand the heliosphere, the protective bubble of particles and magnetic fields generated by the Sun, informing them as to its shape and its role in protecting Earth from the energetic particles and other radiation found in the interstellar environment. At the same time, the vehicles are helping those scientists also understand the nature of the environment beyond our solar system.
However, whilst powered by radioisotope thermoelectric generators (RTGs), which convert heat from decaying plutonium into electricity, the two vehicles have a limited source of power, the RTGs generating less and less electricity as the plutonium degrades.
Thus far, the flow of electricity to the science instruments has been maintained by means of turning off other systems as they’ve ceased being required – such as the high-power camera systems – and those which do not contribute to the science mission or communications. Nevertheless it has been estimated by late 2023, Voyager 2 would be unable to generate sufficient power to manage its instruments, and NASA would have to start turning them off one by one.
To avoid this, engineers carried out a review of the craft’s systems, and realised that the voltage regulation system, designed to protect the science instruments against unexpected surges in the flow of electricity to them, has a small percent of power from the vehicle RTG specifically dedicated to it; a reserve that isn’t actually required, as it also works off the primary supply. The decision has therefore been taken to release this reserve and allow the instructions access it.
This does mean that if there is a serious voltage issue on the vehicle, the regulator might not be able to deal with it – but as engineers note, after 45 years of continuous operations, the regulators on both of the Voyager craft have been perfectly stable and have never needed to draw on the reserve. While the amount of power freed-up by the move is small, it nevertheless means NASA can forestall any need to start turning off instruments until 2026.
The same approach can also be taken with Voyager 1, although the situation there is less critical at that craft lost one of its science instruments relatively early in the mission, leaving it with sufficient power to keep the remaining instruments through until the end of 2024 before decisions on releasing the power reserve needs to be taken.