Transcription: In 1945, the American astronomer Sharpless said the orbit time of Phobos, one of Mars's two satellites, was growing regularly shorter and shorter. Is this true, professor? Yes, it is. Sharpless overestimated the phenomenon, but Phobos is getting closer to the Martian surface, and consequently it's orbiting faster and faster. So eventually it's going to crash into Mars. One day in all likelihood it will, but not for about 40 million years. Is it true that Phobos is a satellite of Jupiter captured by Mars? It's highly plausible.
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