[meteorite-list] ESA's Mars Sample Return Container

[Ron Baalke]

http://www.esa.int/Our_Activities/Space_Engineering/Martian_box_of_delights

Martian Box of Delights
European Space Agency
October 29, 2013

[Image]

This spherical container has been engineered to house the most scientifically 
valuable cargo imaginable: samples brought back from the Red Planet.

Still probably many years in the future and most likely international 
in nature, a Mars sample-return mission is one of the most challenging 
space ventures possible for robotic exploration. 

A robust, multifunctional sample container is an essential link in the 
long technical chain necessary to make such a mission successful.

Weighing less than 5 kg, this 23 cm-diameter sphere is designed to keep 
martian samples in pristine condition at under –10°C throughout their 
long journey back to Earth.

First, the sample container must be landed on Mars, along with a rover 
to retrieve a cache of samples carefully selected by a previous mission, 
according to current mission scenarios. 

The container seen here hosts 11 sealable receptacles, including one set 
aside for a sample of martian air.

Then, once filled, it will be launched back up to Mars orbit. There it 
will remain for several days until a rendezvous spacecraft captures it. 
To ease the process of rendezvous, the sample container carries a radio 
emitter and retroreflectors for close-up laser ranging.
                                                                      
Before being returned to Earth, the container will be enclosed in another 
larger bio-sealed vessel to ensure perfect containment of any returned 
martian material. This container will then be returned to Earth for a 
high-speed entry.

"Because there is the potential, however remote, that the samples contain 
alien life, we have to comply with strict planetary protection protocols 
not to bring them into contact with Earth's biosphere," explained Benoit 
Laine, Head of ESA's Thermal Analysis and Verification section, who oversaw 
the sample container project.

"In effect, the parachute technology is not reliable enough - which means 
the container must be able to withstand a crash landing without parachute. 

"The mission design therefore does not include any parachute, and the 
capsule literally falls from Mars onto Earth, decelerated only by the 
pressure on the heatshield through Earth's atmosphere, and by the impact 
at landing."

While the sample container is a proof-of-concept design rather than actual 
mission hardware, it is fully functional and has undergone testing in 
simulated thermal conditions, including a 400 g shock test. 

"This challenging project drew on the expertise of multiple ESA specialists," 
added Benoit. "It incorporates mechanical systems covering structural, 
thermal and mechanisms engineering but also communications, antennas and 
power - it has of course to incorporate a highly reliable battery."

The prime contractor for the project, which was supported through ESA's 
Aurora programme, was French company Mecano I&D. Activities to prepare 
for a Mars sample mission continue, including a refinement of the sample 
container design, coordinated by the future missions preparatory office 
of ESA's Directorate of Science and Robotic Exploration.