In September 2007, the European Space Agency (ESA) will launch its Foton M3 microgravity mission from Baikonur. The spacecraft will carry the Young Engineers' Satellites (YES2) payload. The goal of this experiment -- designed by 500 European students -- is to send a 6-kilogram package from space to earth. This spherical parcel, named Fotino, will be attached at the end of a 32-kilometer-long tether. This tether, made of Dyneema, will have a thickness of only 0.4 millimeter. When it's completely deployed at an altitude of about 250 kilometers, it will be cut and Fotino will re-enter the atmosphere to land in Russia, inaugurating the first space postal service.
The above illustration shows how the YES2 experiment should work. "The Fotino capsule descends on a tether and reenters Earth's atmosphere. A parachute then returns it safely to the ground." (Credit: Marco Stelzer, for ESA) Here is link to a page containing other images about the YES2 project.
As you can see on the image above, "there are three main components of the experiment: FLOYD -- the YES2 deployment mechanism located on the Foton spacecraft; MASS -- the Mechanical Acquisition and Support System; and FOTINO -- a small spherical capsule, with a diameter of 40 cm and a mass of 5.5 kg."
Here are some details -- given by the YES2 project page -- about how the Fotino will come back to Earth.
During the flight, FLOYD will eject the other two components. There will then be controlled deployment of a 30 km long tether. Orbital dynamics will cause the Fotino capsule to be positioned in front of the mother spacecraft. By bringing the deployment to a halt, a pendulum-like swing will be induced. When the capsule and tether are swinging through the local vertical, the tether will be cut. Since the capsule will then be going too slowly to stay in orbit, it will begin to re-enter the atmosphere from an altitude of about 250 km, protected by a heat shield made of novel materials. Once it reaches an altitude of 5 km, a parachute will deploy to ensure a soft landing on the steppes of Kazakhstan.
And here is the conclusion of the ESA news release mentioned into the first paragraph of this post.
If YES2 is successful it will be the first proof that 'space mail' can be sent to Earth using a relatively simple and cheap mechanism. In theory the re-entry capsule could weigh as much as tens of kilograms, says YES2 engineer Fabio De Pascale from Italy. Enough to send experiments from the International Space Station down to scientists on Earth...
I don't know if this experiment will be successful, but you can follow the daily progress of the Young Engineers' Satellite 2 website,which is designed like a blog, but doesn't have any RSS feeds.
Sources: European Space Agency, May 10, 2007; and various websites
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