The Solar wind-Magnetosphere-Ionosphere Link Explorer (SMILE), representing the most ambitious China-Europe collaboration in space science to date, has successfully passed all environmental tests at ESA's European Space Technology Centre (ESTEC).

Key Mission Progress:

• December 2024: Flight model platform shipped from Shanghai to ESTEC
• January 2025: Successful integration of Chinese platform and European payload modules
• February-March 2025: Completed electrical interface tests between the satellite platform and payload module, solar panel illumination, electromagnetic compatibility evaluations， and AC residual magnetism test of the entire satellite. 
• April-May 2025: Passed rigorous mass properties, sinusoidal vibration, noise, andsolar panel deployment and shock tests
• July 9, 2025: Concluded comprehensive thermal vacuum testing

The successful completion of environmental testing marks a crucial step toward launch readiness. Final preparations now enter their last phase, including: deployment of the magnetometer boom and protective cover of the ultraviolet aurora imager post-thermal vacuum testing, residual magnetism testing of the entire satellite, integrated system testing, and interface testing between the satellite and the launch vehicle.

All remaining tests are scheduled for completion by early September 2025, after which the satellite will enter pre-launch storage awaiting its launch window.

Fig.1 Transportation of the flight model satellite platform (left), transportation of the flight model satellite platform from Amsterdam Airport to ESTEC (right)

Fig.2Electrical interface testing (left), integration of the entire satellite (right)

Fig.3 Solar panel illumination test (left), electromagnetic compatibility test (right)

Fig.4 Sinusoidal vibration test of the entire satellite (left), noise test of the entire satellite (right)

Fig.5Thermal vacuum test of the entire satellite