Where does this come from, and can I check it?

In geostationary orbit the spacecraft spends about 72 minutes of each day in Earth's shadow and draws on stored power. The figure is taken from NASA, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a technology fact?

Yes. It sits on the Technology shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Satellites run on batteries twice a day

In geostationary orbit the spacecraft spends about 72 minutes of each day in Earth's shadow and draws on stored power Solar panels charge a battery while the satellite is in sunlight, and the battery carries the load during eclipse, which happens near the equinoxes for a geostationary satellite. Around those dates the spacecraft enter shadow within minutes of the same clock time, a period operators call eclipse season. Deep space missions face far longer dark periods and rely on radioisotope generators instead. It sits in Mondo's technology collection, one of 200 facts that each trace back to the reference below.

Where this comes from

NASA

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Tags: satellites, power, batteries

Satellites run on batteries twice a day: the short answers

Where does this come from, and can I check it?: In geostationary orbit the spacecraft spends about 72 minutes of each day in Earth's shadow and draws on stored power. The figure is taken from NASA, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a technology fact?: Yes. It sits on the Technology shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.