Some new details about Yinghuo-1:
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designers were still puzzling over how to keep the solar-powered probe functioning during seven "long shadow periods."
The probe would have to pass through seven periods of 8.8 hours in darkness when the sun would be obscured by the red planet, with temperatures plunging to 200 degreesbelow Celsius. While it could turn itself off to conserve energy, the concern was that it might "freeze to death" and not be able to turn itself back on.
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