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In August, a Russian booster rocket failed to place two communications satellites into target orbits, stranding the Russian Express MD-2 and Indonesia’s Telkom-3 satellites in a low orbit where they could not be recovered.

A Russian robotic probe designed to study a moon of Mars got stranded in Earth’s orbit after its launch in November and eventually came crashing down in January.

A few months before, a Soyuz booster rocket similar to those ferrying crews and cargo to the International Space Station failed, prompting officials to consider leaving the space outpost unmanned.