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Artist's impression of the MSL Sky Crane (credit NASA)
With just under a week to go everyone is going ‘Mars Mad’. The reason for this is that the Mars Science Lab that was launched back on November 26th last year is finally approaching it’s destination. Landing is scheduled for 1:31 EDT ( 5:31 GMT ) on the 6th August 2012.
The MSL is a spectacular spacecraft which will be pioneering the Sky Crane landing mechanism. This really is the transformation of science fiction into science fact! The concept is that after entry into the Martian atmosphere a parachute will deploy, shortly after the heat shield will separate and fall away. After this the lander’s jets will fire and the lander will be released from the protective back shell which has been keeping the lander safe in it’s journey across space.
Now the lander is in a period of powered descent with the Curiosity Rover held as a single unit. As the lander reaches 20 metres above the Martian surface the rover is released to fall to the ground on bungee lines. After touchdown the Sky Crane will power away and land a safe distance from the Rover.
The landing is a totally autonomous, and has to be for 2 reasons: Firstly it takes nearly 14 minutes for a signal to be sent from Earth to be received on Mars so control from Earth is not practical; Secondly the landing will occur in a period of communications blackout. The later issue has been overcome to an extent by the repositioning of the Mars Odyessy space craft, which can be used as a relay when MSL is out of direct contact.
The entire process of landing on Mars from orbit takes about 7 minutes so the success of the mission will not be known for about 20 minutes after the start of the entry manoeuvre.
MSL Landing sequence (Credit NASA)
Artists impression of Curiosity the MSL Rover (credit NASA)
