Skydive to provide crew escape data
9 October 2012 Last updated at 04:33 BST
Austrian Felix Baumgartner's skydive from 120,000ft should provide data to help with future space emergencies, say scientists.
It is likely to aid the design of escape systems that will allow humans to exit vehicles at high speed and at high altitude.
Dr Jon Clark is the medical director on Baumgartner's Red Bull Stratos project. He told our correspondent Jonathan Amos about the current state of knowledge on what happens to the human body in a supersonic airflow.