An artist's concept of the Mars Express orbiter near the Red Planet. Photo: ESA

Initial assembly on Europe's Mars Express mission is complete, leaving the craft's basic structure ready for a barrage of tests through the next month. Mars Express is due for a June 2003 launch toward Mars, where it will enter orbit around the red planet.

The flight structure, which ESA calls the skeleton of the spacecraft, has been under construction at the Contraves facility in Zurich, Switzerland, for some time now. The completion of assembly comes right on schedule, indicating that the program is still set for a launch in 2003.

"The tests are starting on time. If you look at our planning from the beginning of the program, we're keeping to the schedule. It's extremely pleasing," said Don McCoy, the manager of the assembly and testing phase of the Mars Express mission.

The upcoming tests will continue until some time in February, making sure that the now-scanty craft meets design requirements set by ESA. After that milestone is passed, the spacecraft will make a year-long whirlwind trip around Europe to gather its various experiments and systems, making it an almost fully space-worthy vehicle.

At Contraves, Zurich, Switzerland engineers were celebrating the readiness of the Mars Express flight structure to undergo tests to ensure that it meets its design requirements. Photo: ESA

Throughout the coming year, the probe will first travel to the United Kingdom where Astrium will attach the craft's propulsion system. Then, it will take a trip to Alenia Spazio in Italy to receive mock-ups of the mission's vital instruments and systems. The newly integrated parts will be tested in June after Mars Express treks to Toulouse, France. Once the analysis is successfully completed, the spacecraft will travel back to Italy, where the mock-ups will be removed from the flight structure, and the actual flight models will be added.

Alenia Spazio already has experience with the assembly and testing phases of the manufacture processes of similar missions. In fact, the company's Italian facility just received ESA's Rosetta flight structure on January 17, which will eventually be built up for a launch just months before that of Mars Express. To simplify the process and to lower program costs, around 60 percent of all Mars Express systems -- including the main computer, transponders, low-gain antenna, and gyroscopes -- stemmed from similar systems used on the Rosetta probe, which will rendezvous with a comet.

"Alenia is well suited to the Mars Express assembly, integration and verification, as they are currently performing similar duties for Rosetta," McCoy said.