Two articles ago, I intimated that the Perseverance Rover was scheduled to land on Mars on Febuary 18 if everything went according to plan. Nearly 50 percent of all attempts to land on other planets have failed so far. It was not a given, therefore, that Perseverance would successfully land on Mars.
The Amercian National Aeronuatical Space Administration (NASA) has an enviable track record of landing stuff on celestial bodies, Mars in particular. It has landed several objects on Mars, but has also had its fair share of failure. NASA’s Mars Polar Lander crash-landed near the Martian South Pole in 1999, for example, but by and large NASA has chalked up impressive success as far as landing craft on Mars is concerned.
The Perseverance mission referred to above successfully landed on the said February 18 2021. The landing has been described as “flawless” as all the operations happened like clock-work.
What makes landing on Mars (or other distant bodies) a big challenge is that it is not possible to send instructions to the spacecraft and expect them (the instructions) to be executed within the time it takes to travel from the top of the atmosphere to the surface. From the time the spacecraft hits the top of the Martian atmosphere, it takes seven minutes to reach the ground. If an operator on Earth tried to remote control the craft, it would take almost 11 minutes for the signal to travel one way and another 11 minutes to travel back. By that time the craft will already have hit the surface. It is, therefore, necessary to create a computer programme that will navigate the spacecraft through the Martian atmosphere until it lands. And this is exactly what happened with Perseverance, just as it had happened with Curiosity in 2012.
During the descent, motion pictures were taken by several cameras mounted in strategic positions on the craft. These pictures were not relayed in real time as they had to be gathered then properly assembled by the experts, a process which took days to complete.
The live broadcast on February 18 2021 did not show pictures of the spacecraft landing, but only announced what was happening at what time. Announcements came at the entry into the atmosphere, the deployment of the parachute, the shedding of the heat shield, the firing of rockets on the descent stage, the lowering of the rover on cables by the skycrane and the touch-down. Of course, the announcement of each operation was coming 11 minutes after the event for reasons explained earlier.
On Monday, February 22, NASA released a video of the landing that had taken place four days earlier. It contained stunning frames taken by the various cameras during the descent of the rover. Some showed the rover resting on the ground and its surroundings.
Perseverance is a six-wheeled rover, the size of an SUV, and weighing just over a tonne. It is the heaviest object to have landed on Mars so far and its landing site was the trickiest ever attempted. Perseverance passed with flying colours and is now undergoing numerous “health” checks to find out if it is ready for the demanding scientific work it was designed to carry out on Mars.
The major objective of the Perseverance’s mission is to look for evidence of past microbial life on Mars. It was deliberately made to land in Jezero Crater, which used to be a lake in the distant past. Where there is water, there are chances of life having evolved or even thrived. All life leaves what scientists call bio signatures after it has disappeared. It is these bio signatures that Perseverance will be looking for in Jezero Crater.
It will also scoop some Martian soil and package it in small cylinders which will eventually be collected by future missions and returned to Earth for closer analysis. The plan is that these Martian samples will get to Earth by the year 2031.
A small experimental helicopter hitch hiked its way to Mars aboard Perseverance Rover. It is still on the belly of the rover, waiting to be released after two months so that it can attempt to fly on Mars. If and when successful, the helicopter, which was christened Ingenuity, will be the first object to achieve powered flight on another world in history and will pave the way for similar helicopters to be deployed for exploratory work in future missions.
As Perseverance made its landing on February 18, very few Malawians knew that this was happening. Fewer still watched it with the rest of the world.