Russia confirmed on August 20 the total failure of its Lunar-25 lunar mission. The lander had to brake to lower its orbit when it was planned to land on the surface on the 21st… But the maneuver was too pronounced, and the vehicle struck our natural satellite. A blow for Russian space!
The Indian lander Chandrayaan-3 is ready, for its part, to try to land on Wednesday 23.
Just one more move?
After its launch on August 11, the Russian Luna-25 lander succeeded, on August 16, in its maneuver to enter orbit around the Moon. The mission therefore entered a phase which is not a formality, even if it is not recognized as being the most complex of a lunar journey. Indeed, the orbit of August 16 did not allow landing on the 21st, on the planned site near the South Pole. It was therefore necessary to carry out a small series of braking operations to lower its orbit and prepare for the maneuvers to come.
On August 19, the last of them was scheduled, to slow down and achieve orbital parameters of 18×100 kilometers in altitude (the periapsis, the lowest point of the orbit, only passing 18 kilometers from the surface). This type of braking is sent in sequence to the lander, which is not permanently in communication with the Earth, and the latter triggers it at the scheduled time autonomously. Then (or even during, if the observation allows it), Roscosmos, the Russian agency, normally resumes contact and observes the results of the maneuver. But this August 19, after the planned braking, Luna-25 no longer responds.
Face reality, be realistic
The Russian authorities will take almost half a day to confirm the bad news: the planned maneuver did not go well, and it seems that the Luna-25 lander braked too much, either because of an ignition motor too long or too powerful.
Given its orbital parameters, a very precise ignition was needed: at 4 meters per second (14.5 km/h), the final altitude went from 18 kilometers… to zero. The vehicle therefore braked too much, and as its programming did not prepare it to land at that moment, it crashed on the lunar surface. The agency has obviously planned an investigation to find out exactly what happened.
Russia has exploration problems
This crash is a significant event for Russian space, and it is a blow in several respects. First, because landing on the Moon is always seen as a prestigious mission. Given the geopolitical context of Russia after the invasion of Ukraine, successfully landing on the lunar South Pole, and showing the world scientific results of soil analysis would have represented a powerful communication tool on Russian power . Conversely, this failure is an opportunity for many observers to evoke a downgraded Russia, even a mission botched by haste.
On the other hand, it is a blow for the country economically (the mission, in preparation for more than a decade, has cost tens of millions of euros), scientific and technical. Indeed, since the end of the communist era, space Russia has not succeeded in a single major space exploration mission: Mars 96, Phobos-Grunt and now Luna-25 have been bitter failures… And this lunar mission was essentially a technology demonstration in anticipation of future vehicles that were supposed to be more ambitious.
Finally, it reminds us that when we want to land on the Moon, mistakes are inexcusable, and that there are many sources of failure. Over the past ten years, only China has managed to land there three times. India will try, Wednesday, August 23, to succeed him…
Source : https://spacenews.com/luna-25-crashes-into-moon-after-orbit-maneuver/
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