Young Engineers' Satellite 2

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Young Engineers' Satellite 2
Type: Research satellite
Operator: European space agencyESA ESA
COSPAR-ID : 2007-040A
Mission dates
Dimensions: 35 kg
Begin: September 14, 2007, 11:00 UTC
Starting place: Baikonur
Launcher: Soyuz-U
Status: completed
Orbit data
Rotation time : 90 min
Orbit inclination : 63 °
Apogee height :  258 km
Perigee height :  280 km

The Young Engineers' Satellite 2 ( YES2 ) was a satellite that was built almost exclusively by students on behalf of the ESA Education Office by Delta-Utec SRC. The satellite, which weighs around 35 kilograms, was launched on September 14, 2007 at 11:00 UTC from the Baikonur Cosmodrome in Kazakhstan on a Soyuz U launcher as part of the Foton M3 mission. After conducting a space tether experiment, it burned up in the earth's atmosphere on September 26, 2019, as planned.

Mission goal

The task of the Yes2 mission was to unwind a so-called tether, a 0.5 mm thin and 30 km long rope made of Dyneema synthetic fibers, at the end of which was the Fotino re-entry capsule . Fotino was supposed to be brought onto a re-entry trajectory with the help of the tether without the otherwise usual rocket stages or engines, in order to land safely again in Kazakhstan on an integrated parachute.

The project

In this project, most of the work (such as design, construction and integration) was done by students and young engineers.

In the initial phase, in addition to the Delta-Utec SRC location, the tasks were also distributed across five universities. These "Centers of Expertise" were: the University of Kent (Great Britain), the University of Patras (Greece), the University of Modena and Reggio Emilia (Italy), the Niederrhein University of Applied Sciences in Krefeld (Germany) and the State University of Aerospace Samara (Russia). There the work was led by a professor and coordinated by Delta-Utec.

In the final phase, the work concentrated more and more on the Delta-Utec office in Leiden (Netherlands) and the nearby ESA center ESTEC in Noordwijk. There the satellite was finally assembled and tested for several weeks.

The test campaign included:

  • determining the electromagnetic compatibility in the EMC test chamber "Maxwell" of the ETS test center,
  • simulating space conditions in the thermal vacuum chamber,
  • a vibration test on the "shaker table" to simulate the forces that occur during take-off and to ensure that the satellite can withstand them undamaged,
  • Function tests of all components and systems.

At the beginning of May 2007 Yes2 was handed over to ESA and sent to ZSKB-Progress in Samara (Russia), where the satellite was screwed to the Russian Foton-M3 for the first time in June 2007 for test purposes. After the tests were completed, it was brought to Baikonur separately from Foton-M3, where all parts were assembled and launched into space on September 14, 2007.

Structure of the satellite

FLOYD

The Foton Located YES2 Deployer (FLOYD) is permanently mounted on the Russian Foton-M3 and houses most of the Yes2 electronics as well as the tether. FLOYD consists of a hexagonal canister in which the tether is wound on a spool. The electronics are located in boxes on the one hand above the canister in the so-called "Attic" and on the other hand in a cube-shaped box called "XBOX" attached to the side of the canister. The “ejection system” and the “barber pole” are located above the attic. The barber pole acts as a brake for the tether. Here, with the help of a stepper motor, the tether is wound around a round, rough rod if necessary, in order to brake the tether by means of friction.

MASS

The Mechanical and data Acquisition Support System (MASS) is attached to FLOYD at the beginning of the mission. The free end of the tether is attached here. MASS consists of a round base plate, a cylinder mounted on it and a funnel mounted on the cylinder. Further boxes with electronics are attached around the cylinder to control the release of the re-entry capsule.

Fotino

Fotino is a spherical capsule weighing around 5.5 kg and consisting mainly of silicon , Aluvac , polyurethane and aluminum oxide . At the beginning of the mission it was fastened with straps in the MASS funnel. Inside there are instruments for position determination and communication.

Mission history

Yes2 was activated on September 25, 2007, the eleventh day of the Foton-M3's twelve-day mission. A pyro cutter was then ignited, which released the holding elements between MASS and FLOYD. Three springs then pushed MASS away from FLOYD. The tether located between the two elements slowly unwound from the coil located inside FLOYD.

After a 3380 m long section of the tether had been unwound, it was stopped in order to align the MASS-Fotino team with the landing zone in Kazakhstan. Then the tether should be unwound over its entire length of 30 km. As a result, MASS / Fotino was in a lower orbit than Foton-M3 and was therefore faster. The tether, however, prevented rushing away and forced MASS / Fotino to slow down and to swing backwards.

Initially it was assumed that the tether had already been cut at a length of 8.5 km. After evaluating all flight data, however, the project team assumes that the tether up to the full length of 31.7 km, i.e. H. was processed longer than planned. From the flight data it was possible to calculate that Fotino fell near the Aral Sea . The probe has not yet been found.

After Fotino was detonated, the tether on the FLOYD side was detached and burned up together with MASS in the atmosphere, as did FLOYD together with Foton (except for the return capsule) after the end of the Foton M3 mission.

See also

Web links