One more disappointment at the start of the year for the small Lunar Flashlight mission, which adds to the long list of problems with these minimalist vehicles on lunar missions… They are still as promising, but the technical challenge is more complex than expected. !
It remains to be seen whether they are as practical as was envisaged with all these rescues.
Small, but (not) strong
On paper, these missions of small 6U Cubesats to the Moon are very attractive. For a few million dollars and big savings on a space launcher, it is possible to send these boxes which weigh only 25 to 30 kg, with a single scientific instrument, on a mission to the Moon. An agency like NASA, which has very specific needs for our natural satellite and does not have the budgets or the needs for a new probe of a few tonnes sent for a mission of one or two decades, is a godsend: few development, low costs, a few months of survival and results to be studied afterwards. But if the CubeSat format is all the rage in low Earth orbit, there is still a lot of progress to be made for lunar missions.
The CAPSTONE mission, which took off last July, is a good example. On three occasions during its journey, the teams on the ground had to “save” the small probe: failure and restart of its on-board computer, thruster problem, communication… Since its arrival in November, the mission has been satisfactory and NASA has been able to happy to see that the orbit she wanted to test with CAPSTONE is, it seems, more stable than expected. Nevertheless, the small vehicle broke down again from January 26 to February 6. More boring, he carried out one of the highly anticipated tests of his mission, an exchange with the lunar probe LRO which was to allow him to locate himself in orbit. But the exchange of communication, it seems, did not work as planned. The agency will try its luck again.
Occasional flashlight
CAPSTONE is not really an isolated case. Many units sent in addition to the ARTEMIS I mission broke down, were unable to maneuver or missed their objective. In a sense, this is not a big deal given the small budgets involved, but it is also, unfortunately, a poor scientific return for these promising instruments. One of the latest failures is that of Lunar Flashlight. A CubeSat 6U which took off on December 9 for the Moon, with the Japanese Hakuto-R lander. Unfortunately, in January, its thrusters (equipped with a new technology, already tested in Earth orbit) broke down one after the other: the only one the team could still count on for injection into lunar orbit saw its performance “degrade significantly over time”. NASA is trying to assess its trajectory to find out if it is possible to pass Lunar Flashlight (its laser instrument must illuminate the craters to find traces of lunar ice) over the South Pole several times thanks to its course ellipsis today.
These high-risk “mini-missions” will nevertheless allow the agency as well as American companies and universities to perfect themselves in this new field, before a next generation of small vehicles which will be (it is to be hoped) more reliable. . Until then, there are still ongoing missions around and on the Moon!
Source : space news
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