Engineering students say Go for tethered YES2 satellite

William Atkins
Monday, 02 July 2007 19:34

Science - Space

After five years of research and development work by the students, various reviews and tests have been successfully completed. The passing marks for the YES2 mission should lead to the launch of the spacecraft in September 2007.

During its YES2 mission, the ESA Foton spacecraft will be sent into orbit about the Earth. The spacecraft contains the FLOYD deployment system that will deploy two objects: a mini-satellite called MASS (Mechanical Acquisition and Support System) and a small, spherical re-entry vehicle called FOTINO. The FLOYD system will also deploy a 32-kilometer (19.9-mile) long tether.

The FOTINO capsule will be located at one end of the tether and the MASS vehicle will be positioned at the other end. The pair—connected by the tether—will be positioned in front of the Foton spacecraft as it circles the Earth.

After the tether is fully deployed, a swing-like motion will be introduced into the system. Soon thereafter, the tether will be released, causing the FOTINO capsule to reduce its speed and begin to re-enter the Earth’s atmosphere. At about five kilometers (3.1 miles), a parachute will open to enable the FOTINO to land safely.

The spacecraft is 36 kilograms (79.4 pounds) in weight (on Earth). The FOTINO re-entry vehicle has a weight of 5.5 kilograms (12.1 pounds) and a diameter of 40 centimeters (about 15.8 inches).

The tether, which is 32 kilometers in length, is considered the longest tether to ever be deployed in space. It is made from Dyneema®, an extremely strong fiber that is only 0.4 millimeter (about 0.01575 inch) thick and weighs only five kilograms (about 11 pounds). In addition, the tether is considered the longest artificial structure ever to be deployed in space.

YES2 will be launched as part of ESA’s Foton-M3 microgravity mission from the Russian Baikonur Cosmodrome. The Foton spacecraft will be launched using a Soyuz-U rocket.

Nearly 500 students from countries within the European Union, the United States, Japan, Canada, and Australia have worked on the design phase of the YES2 mission. About 60 students worked on the actual development of the hardware and software and the assembly of the component parts.

The YES2 mission is the first use of a tether to de-orbit a payload from space and return it to the Earth. This tethered experience will help to promote further low-cost returns of payloads from space to the Earth.

The website of the YES2 project is: http://www.yes2.info/. Additional information is found at the ESA website: http://www.esa.int/esaED/SEMVJ1AATME_highereducation_0.html.