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BEIJING, September 30, 2026 – The Solar wind Magnetosphere Ionosphere Link Explorer (SMILE), a joint mission between the Chinese Academy of Sciences (CAS) and the European Space Agency (ESA), has successfully passed its in-orbit commissioning review and officially entered the science operations phase. Today, both agencies released the first batch of images and scientific data from the satellite's four instruments.

SMILE was launched on May 19, 2026, from Europe's Spaceport in Kourou, French Guiana, aboard a Vega-C rocket. After about a month of orbital maneuvers, it reached its science orbit — with a perigee of 5,120 km and an apogee of 120,900 km — on June 20. Since then, the payload module and all scientific instruments have been activated in turns, completing in-orbit checkout and calibration, and have started delivering valid scientific data as expected.

The satellite is operating nominally, with all functions and performance targets verified. The CAS team independently carried out payload module operations, paving the way for the first-ever global imaging of solar wind–magnetosphere interactions and real-time observation of the coupling process. Both sides commended the collaboration and expressed full satisfaction with the commissioning results.

First Batch of Observations and Data

The released data include uninterrupted panoramic auroral images of the Northern Hemisphere from UVI, the X-ray image of supernova remnant in the Large Magellanic Cloud. from SXI, and high-resolution magnetic field and ion data from MAG and LIA — the first of their kind from such a high Earth orbit.

UVI (Ultraviolet Auroral Imager) – Switched on July 16, UVI has captured the first uninterrupted panoramic images of the Northern Hemisphere auroral oval and its fine-scale structures. Auroral images provide a visual window into mass and energy transport in the magnetosphere. UVI offers the longest continuous spaceborne auroral monitoring capability, with observation windows of up to 44 hours and a best temporal resolution of 5 seconds. From SMILE's unique highly elliptical orbit, UVI will visualize the entire solar wind–magnetosphere coupling process.

Figure 1: Aurora image taken by UVI on August 4, 2026 (raw, unprocessed). Credit: CAS & ESA / SMILE / UVI

SXI (Soft X-ray Imager) – Turned on June 27, SXI is operating normally and has completed its in-orbit calibration. With SXI, SMILE becomes the first spacecraft to perform detailed, long-duration X-ray observations of Earth's magnetosphere. The first test image (Figure 2) shows a supernova remnant in the Large Magellanic Cloud, about 160,000 light-years away — a standard calibration target. Once routine science operations are fully underway, SXI will observe the soft X-rays emitted when the edge of Earth's magnetosphere is struck by charged solar wind particles. Initial data indicate some stray light effects, which the joint team is actively addressing through instrument tuning and software updates.

Figure 2: SMILE's first X-ray test image shows a supernova remnant in the Large Magellanic Cloud. Credit: ESA & CAS / SMILE / SXI

MAG (Magnetometer) – Powered on June 27, MAG measures magnetic fields in the solar wind and magnetosphere, a key parameter linking the solar wind, magnetosphere, and ionosphere. After calibration, it achieved a resolution better than 0.1 nT, capable of detecting subtle solar wind variations. Flying along SMILE's unique orbit, MAG traverses high-latitude magnetopause and magnetosheath regions that have rarely been explored by previous missions. Figures show clear noise reduction after boom deployment, distinct magnetic signatures across the bow shock, and strong consistency with OMNIweb solar wind data.

Figure 3: Comparation of Magnetic Field before and after Boom Deployment

Figure 4: Magnetic Field Data Obtained by the SMILE Satellite Crossing the Bow Shock

Figure 5: The Solar Wind Magnetic Field Intensity Measured by the SMILE Satellite is Consistent with the Data from Omniweb Satellite

Figures 3–5: Credit: CAS & ESA / SMILE / MAG

LIA (Light Ion Analyzer) – Activated on June 30, LIA measures ion energy, direction, and flux to derive three-dimensional velocity distribution functions and physical parameters such as velocity, density, and temperature. It has captured ion energy spectra (10 eV–25 keV) and angular distributions across 24 azimuthal and 16 elevation angles, consistent with typical ion beam distributions. These data provide critical input for understanding the ion environment along SMILE's orbit and interpreting SXI and UVI images.

Figure 6: Ion Energy Spectrum Measurement Data

Figure 7: Ion Energy Spectrum and Angular Distribution

Figures 6–7: Credit: CAS & ESA / SMILE / LIA

A New Milestone in China–Europe Space Cooperation

SMILE is the finale of CAS's Strategic Priority Program on Space Science (Phase II) and the largest international space science collaboration led jointly by China and Europe since the Double Star Program (2003). It represents a new milestone in mission-level, all-round cooperation between Chinese and European scientific communities.

The satellite will use advanced imaging to simultaneously observe the magnetopause, polar cusps, and the auroral oval. Combined with in-situ measurements from space and ground, it will deliver the first panoramic view of solar wind–magnetosphere interactions — a process that drives the entire space weather chain. The mission promises to open new perspectives in magnetospheric physics and directly contribute to predicting and mitigating space weather hazards.

SMILE was jointly developed by CAS and ESA. The satellite comprises a Chinese-built platform (developed by the Innovation Academy for Microsatellites of CAS) and a European-built payload module (by Airbus). Its four instruments are: SXI (University of Leicester), UVI (jointly by NSSC/CAS and ESA's ESTEC), and MAG and LIA (both by NSSC/CAS). The launch vehicle — a Vega-C built by Italy's AVIO — and launch services were provided by ESA, marking the first time a Chinese satellite was launched from Kourou. ESA handled tracking and telemetry before separation, while CAS took over afterward. Primary science data downlink uses ESA's O'Higgins station in Antarctica, relayed via the European control center, with China's Sanya station as backup (developed by the Aerospace Information Research Institute of CAS). The ground support and science application systems are operated by NSSC.

The successful entry into science operations marks a new chapter in China–Europe space science cooperation and promises major advances in understanding solar wind–magnetosphere interactions and improving space weather prediction.

Figure 8: Artist's impression of the SMILE satellite. Credit: CAS