A Fiery Chariot
The return of Mark Shuttleworth and the cosmonauts on Sunday morning at 03.51GMT is going to be spectacular. As the capsule plummets back through the Earth's atmosphere, temperatures on the outside of the capsule wall will rise to 10 000°C. The crew will be well insulated on the inside and will be safe from the extreme temperatures that will scorch and blacken the exterior.
All radio contact is lost while the capsule enters the upper layers of the atmosphere at ten times the speed of sound. Mission control is attempting to bring the capsule down to Earth with the ISS positioned directly above them, in an attempt to lengthen the communication time. The signal from the Soyuz will go to the ISS which will relay a signal to Houston who will in turn relay it to Moscow.
Hit the brakes!
Atmospheric drag will breaks the capsule's fall within a few minutes to a more reasonable speed of only 200m per second. The Traffic Department would be in a tizz if they were doing that speed on a horizontal plane! At an altitude of about 12km a brake parachute opens to reduce the capsule's speed even more. There is back up with emergency parachutes which open at 8km should anything untoward happen.
The capsule is now falling at a more manageable 6m a second as it heads towards to the landing zone in Kazakhstan. Just prior to impact , a set of retro-rockets are fired up to create some reverse thrust to soften the blow.
"It is quite spectacular," says Mark "There is dust and smoke everywhere, but the landing itself is much gentler."
Mark's dad, Dr Richard Shuttleworth, will be on board one of the eight emergency helicopters that will be there to retrieve the three 'stirred and shaken men' from the now soot-blackened capsule. His will surely be a welcome face to Mark after his bumpy return journey from space!
Back to work
Once the three returning heroes have been extracted from the capsule they will be put into quarantine and taken straight to Moscow for treament for the after effects of weightlessness.
"They say everything feels heavy back on Earth. It is difficult to lift your arms and ordinary actions require huge effort," says Mark "We will need a few days' rehabilitation once the flight is over."
The ten days that Mark stayed in space is not a long period of time but he did not have the time for a great deal of exercise on board the ISS. The three ISS crew already on the board have to do one to two hours of weight-bearing excercise to keep their muscles from deteriorating.
Once Mark has re-adjusted to the Earth's gravtity, he will be back at work to complete the last of the scientific experiments. Only once all his work has been done, can Mark really kick back and 'earth' himself with family and friends.
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