The photographs show several of the main stages and results of scientific research made by the descent vehicle of the Rosetta mission, and also show its legacy in the future.
At the beginning of September, the European Space Agency finally found the “Phil” space descent vehicle on the surface of comet 67P / Churyumov-Gerasimenko. Rosetta made this discovery at the last minute when he was about to finish his mission (the Rosetta spacecraft spent nearly two years trying to find the lost Filas).
Here are some photos taken by the Fila apparatus and explanations for them, as well as meaning for future missions.
Finding the “Fila” machine
Fortunately, the Rosette spacecraft still managed to track down the landing module on an image analyzed on Earth on September 4, 2016. It took Rosetta 22 months to find the brave module and everything was in vain. But since the spacecraft was spiraling closer to the comet, a suspicious spot was spotted in the photo, which captured Phila's landing site (its legs protruded above the surface). Interestingly, Rosetta had another month before landing on September 30 and this would have provided more opportunities for detecting Fila.
Fila's Incredible Journey
The path to the surface was not as easy for Fila as one might hope. The harpoons, which were supposed to ensure his safety, could not shoot, so that after landing the apparatus did not fix, but jumped off the surface. He drifted for about two hours, before lying down to rest in a shady spot. But the problem was that “Fila” works on solar batteries, and in the shade he lost a source of energy. These extraordinary images, made by Rosette, fixed the position of “Fila” in the first 30 minutes after its descent. When the surveillance was interrupted, the whole European agency knew only that it was necessary to look for the device somewhere in the east.
Landing Site Overview
This image was taken on November 12, 2014, when “Phil” flew up to its first landing site on comet 67P / Churyumov Gerasimenko - Hagilkiya. Even the few images taken during the descent helped scientists learn more about the comet's surface. One of the main conclusions was made thanks to a high 5-meter boulder, which had “a peculiar bumpy structure and lines of destruction passing through it”. According to ESA, this is the key to understanding how comet boulders are destroyed over time.
Although only about 60 hours of surface data were received from “Fila”, scientists worked feverishly to squeeze the maximum amount of information. Instruments and cameras on the spacecraft continued to work despite the lack of clarity, allowing scientists to obtain an image of the landing, as well as to collect data on the vicinity. Despite the short working time, “Fila” got some interesting information about the comet. For example, the presence of water ice on the first landing site, the detection of hydrogen and carbon in the atmosphere, and the presence of organic compounds on the surface of the comet.
Although “Fila” had a short period of ability to act, his bold descent would help inform about the nuances of planting modules on small objects. A comet is an extremely complex environment for any spacecraft, as there is a risk of eruption, debris and uneven gravity around a tiny object. As demonstrated by “Phil” landing also has many difficulties. The fact is that gravity is so weak that there is a great risk for the apparatus to jump off and swim after the current. ESA and other space agencies use this data to improve the chances of other descents on small objects in the future. One of these missions will be OSIRIS-REX, which will be sent to the Bennu asteroid to take a sample of the surface.