We know that the lander failed. But why?
By: Dhan P.
The Schiaparelli lander plummeted into the surface of Mars on October 19th. But the causes of the crash are under continued investigation, and for very good reasons. The second part of the Exomars mission, a joint venture between the European Space Agency (ESA) and Roscosmos (Russia’s space agency), is slated to launch in 2020, and it includes a rover that would land on Mars with the same system that Schiaparelli used. So, what does the data suggest about the crash?
The data says that there was probably a computer error. The lander jettisoned its parachute too early, and only fired the retrorockets that were supposed to slow it down for three seconds instead of thirty seconds. In addition, the data also suggests that the lander had activated ground instruments while plummeting down towards the surface. This leads to three possible conclusions. Either the onboard system was wrong about the distance to the ground, or it was mistaken about what time it was at during the mission. Another explanation is that both systems went haywire, and this lead to the crash. Newer data suggests it was a problem with the computer calculations, as a slight overload in other data disrupted the calculation that showed the distance to the surface. At one point, the lander calculated it was beneath the surface. Radar data seems to have only compounded this problem.
NASA imagery of the site has also shown some interesting features of the crater and its surroundings. There appear to be dark tails around the crater, not unlike a meteor impact crater. The lander was not going fast enough as it crash landed to make such a tail, so why are they there? The tails may be from the leftover hydrazine propellant in the tanks of the lander, which exploded as it hit the ground. Splotches in the black and white images taken by NASA’s MRO (Mars Reconnaissance Orbiter) appear to be fragments of the lander. Higher definition colour images appear to verify this. The parachute and heat shield have also been spotted by the MRO, and may help determine what exactly went wrong.
The mission is not a complete failure, however. The Exomars orbiter went into orbit smoothly, and the data we got before we lost contact with Schiaparelli will help ESA and Roscosmos scientists figure out what went wrong, and how to prevent it from happening again in 2020. With the orbiter’s success, the ESA and Roscosmos only have to iron out the landing, and not getting to the red planet.
The exact problem with the computer or software has not been pinpointed as of the time of writing, but scientists are already working on the 2020 phase of the mission, which includes a rover to scout the martian surface for signs of life. Once the exact problem with the descent has been found, it will be fixable in the time between now and the launch. Hopefully nothing goes wrong in 2020, and we can continue to look for signs of past and current life on mars – or possibly signs of martian lettuce.