SSETI Express
is a small satellite, similar in shape and size to a washing-machine (60x60x90 cm aprox.). Its weight is about 62 Kg and it carries 24 kg of experiments. Inside this satellite, builded by students, there are 3 pico-satellites with a extremely small size and a weight of 1 kg each one. These satellites will be launched once SSETI Express is orbiting. It's the first time for this kind of maneouvre. This project is a great chance for
testing several designs, including a cold gas actitude control system. Moreover, SSETI Express will take Earth pictures and will be a radio signals station.

This is SSETI Express, once assembled (builded) at the ESA's headquarters in Noordwijk (Netherlands). It's so nice...


The main characteristics of the satellite are:

Dimensions 560 x 560 x 900 mm
Mass 62 Kg
Payload 24 Kg
Lifetime (extensible) 2 months
On-board experiments Solar sensors
Magnetómeters
Digital camera (~100m / pixel, 1280x1024 pixels)
Three picosatellites
Period (time to complete an orbit around the Earth) 90 minutes
Kind of orbit Low altitude heliosíncrone
Mean altitude 686 km
Inclination 98 degrees



   SSETI Express satellite was mainly designed and builded by students, under the supervision of ESA's Educational Department. The main subsystems (power control unit, UHF communications unit, on-board computer, actitude control system, propulsion system and camera) were developed in several european universities. The challenge was the work of 23 university teams, along all Europe, through the internet, to buiild the satellite all together. ESA has supported the project, preparing a detailed plan, joining efforts, supervising the building and testing, and make the launch possible.

   ESA's testing center at Noordwijk (Netherlands) lend us its headquarters and expert people for a detailed test. SSETI Express pass an electromagnetic compatibility test in a special chamber. Moreover, the satellite was placed in a oscilating table, in order to simulate every movement that takes place in the launch moment. The extreme condicions of space (vacuum, extreme temperatures...) were simulated in a vacuum chamber.

   The system working tests took place  at the ESA's technical canter, ESTEC. A terran coverage simulator was connected, through the internet, to the mission control center computer in Denmark. The polish operations team was able to take the control of SSETI Express during the tests, through a far conexion, while they were communicated with ESTEC staff via e-mail.

   There are 18 months since SSETI Express was born to be ready for the launch. Probably, it's the fastest designing and building project ever made. This is the reason for its name: Express.

   SSETI (Student Space Exploration and Technology Initiative) association was the community work to develop SSETI Express. It was created in 2000 by the ESA's Educational Office, in order to get involved european students in space missions. This initiative try to give to the students some experience in this field and prepare them to get a job in space science and technology industry.



There is only one spanish university participating in SSETI Express: University of Zaragoza, working on the satellite Mission Analysis.

   Five physics and mathematics students, under the supervision of Science faculty dean, Dr. Antonio Elipe, and the proffesor  Dr. Alberto Abad, worked on calculate the satellite orbit, groundstation coverage (when we can establish communication), eclipse times and other necesary calculations in the mission analysis of any satellite.

   We are the second generation of students working on this project. Many other have worked before us, so this initiative couldn't be possible withoiut their work. So we would like to thank to Itziar Barat and Rubén Castro (and many others....) the creation of our Mission Analysis team.