As its name suggests, its primary mission was to monitor variations in star light, which it did by observing a single target for a long period of time (up to 60 days).

Led by Principal Investigator Jaymie Matthews, the MOST science team's plan was to use observations from MOST to use asteroseismology to help date the age of the universe, and to search for visible-light signatures from extrasolar planets.

The original SFL application to the CSA is available at https://www.astro.utoronto.ca/~rucinski/MOST_proposal_1997.pdf MOST featured an instrument[4] comprising a visible-light dual-CCD camera, fed by a 15-cm aperture Maksutov telescope.

It was operated by SFL (where the primary MOST ground station is located) jointly with Microsat Systems Canada Inc. (since the sale of Dynacon's space division to MSCI in 2008).

In 2019, MOST photometry was used to disprove claims of permanent starspots on the surface of HD 189733 A that were alleged to be caused by interactions between the magnetic fields of the star and its "hot Jupiter" exoplanet.