Mohammed VI: plan observations across a two-satellite system

Morocco’s Mohammed VI observation system includes Mohammed VI-A and Mohammed VI-B. The national registration submitted to the United Nations records Vega launches on 8 November 2017 and 21 November 2018, respectively, using UTC dates. Avio identifies Thales Alenia Space and Airbus as the spacecraft builders and describes applications including land mapping, development planning, disaster management and monitoring borders and coastlines.

Two spacecraft can offer more opportunities to acquire useful observations, but the increase depends on their orbits, pointing limits, scheduling and the conditions over the target. A pair of optical satellites does not automatically produce a cloud-free image at every requested time. Keep the A and B identities attached to their observations so analysts can check which instrument and processing history produced each result.

Consider a simplified plan for six target areas. Satellite A can image areas 1, 2, 3 and 4 during a chosen period. Satellite B can image areas 3, 4, 5 and 6. There are eight scheduled acquisitions but only six distinct areas. Areas 3 and 4 are observed twice. Whether that overlap is wasteful or useful depends on the objective: repeat observations can reveal change or help compare measurements.

Now suppose cloud blocks B’s observation of area 6, while the other acquisitions remain usable. Five distinct areas have usable imagery. Counting all planned passes would overstate the delivered coverage. A mission report should distinguish requests, attempted acquisitions, successfully returned files and products suitable for the intended analysis. Each count helps diagnose a different part of the service.

Acquisitions are not unique coverage

For a flood assessment, a second image taken after conditions change may be especially valuable. For a map of a stable feature, another clear view of an already covered area might be less urgent than the first view of a missing area. Scheduling is therefore a decision about user needs, not merely maximizing the number of pictures. State the observation time alongside any map intended to support a timely response.

A paired system also needs consistent processing. If one image uses a different correction or spatial grid, an apparent boundary shift may come from processing rather than movement on the ground. A shared quality procedure can compare the observations without pretending that separate instruments are identical. The lesson of the Mohammed VI system is to connect spacecraft opportunities to usable, interpretable products and the decisions those products are meant to support.