Tuesday, July 5, 2011

Genesis Discovery

Despite an unfortunately emphatic return to Earth in which the parachute failed to deploy and the sample return capsule pancaked onto the Utah desert, the NASA Genesis Discovery Mission succeeded. Witness the June 24 issue of Science. The magazine's cover is a photo of the particle concentrator extricated from the spacecraft-pancake. Two articles announce important findings from analysis of the concentrator, changing our understanding of the composition of the primordial solar system. And these are just two high-profile examples of the journal and conference papers occasioned by Genesis samples being sent to researchers around the world who have asked for them. Not bad for a mission with a spectacular equipment failure at the end!

What saved the science was contingency planning. The nominal mission would have had the sample return capsule, dangling under a parachute, delicately snagged in mid-air by a helicopter. But design decisions were driven by considerations of how to salvage the samples even if the return capsule broke. Five silicon collector arrays that had basked in different regimes of the solar wind were each of a different thickness. Every fragment bigger than a breadcrumb revealed what array it came from. The particle concentrator and its matrix were more robust than they might have needed to be. So the concentrator, which was identified in the early proposal stage as being of potentially high scientific value, ended up mainly intact - high value science and all.

No comments: