Whom does NASA trust when it comes to handling precious cargo on another planet? The answer seems to be Lockheed Martin. For all its 10 lander or rover missions to Mars, NASA has involved Lockheed Martin to design and make the critical parts of the landing system — the aeroshell.
At first glance, the aeroshell looks like a rudimentary alien spacecraft. But for those involved in rover and lander missions, the aeroshell is the most critical. It consists of a cone-shaped back shell and a heat shield in the shape of a disc. Together, they are tasked with protecting the spacecraft from the extreme temperatures of interplanetary space as well as punishing heat generated during the landing sequence and touchdown on the planet.
As the name suggests the heat shield bears the brunt of the touchdown sequence. Entering the planetary atmosphere at high speeds generates a lot of heat. To counter it, the shield is made of thermal protective material that was designed at NASA’s Ames Research Center. Called Phenolic Impregnated Carbon Ablator or PICA, this material is capable of withstanding heat up to 5000 degrees Fahrenheit (2760 degrees Celsius) and keeping the spacecraft from harm. The heat shield is also aerodynamically designed to work as a “brake” and slow down the spacecraft during its fall.
The backshell has an aluminum honeycomb structure with graphite-epoxy sheets and hand-packed with a special material called SLA-561V. Invented by Lockheed Martin, this material is made up of silicone and cork and minimizes the weight of the aeroshell. It also supports the parachute and has small thrusters to keep the shell correctly oriented. It also packs batteries and other electronics needed for a safe landing.
Lockheed Martin has been designing and fabricating aeroshells for Mars missions since the 1970s and also supplied the aeroshell for the Perseverance rover that landed on Mars earlier this year.
NASA's next endeavor
NASA’s next mission is a Sample Return mission that will return to Earth the samples collected by the Perseverance rover. This is an ambitious mission scheduled to take place over the next decade. For this, a lander will reach Mars and rendezvous with Perseverance and receive the sample. It will then launch the samples in the Martian orbit that will be collected by an orbiter of the European Space Agency. The orbiter will then return to Earth with the samples.
David Buecher, Lockheed Martin program manager for the Mars Sample Retrieval Lander aeroshell. "By protecting this next spacecraft during its descent to Mars, we're delighted to have a role in the safe delivery of another element of the Mars Sample Return program."