Mondo Knows Facts
Orbiting low means moving fast
At 400 kilometres altitude a satellite needs nearly 8 kilometres a second Orbital speed falls with distance, so low orbits are quick and high ones slow. A satellite at 400 kilometres completes a lap in about 92 minutes. Getting up there takes far more energy than the height alone suggests, because almost all of it is spent on horizontal speed. It sits in Mondo's space collection, one of 200 facts that each trace back to the reference below.
Where this comes from
Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.
Go further
More facts like this
There are five gravitational parking spots near EarthAt L4 and L5 a spacecraft can hold a stable position with minimal fuelRadar tracks tens of thousands of pieces of debrisMillions more fragments are too small to follow but still damagingA comet's tail points away from the SunThe ions are pushed by the solar wind, not dragged behind the motionGeostationary satellites sit 35,786 kilometres upAt that height one orbit takes a day, so the craft appears to hang stillMars launch windows open about every 26 monthsSpacecraft wait for the planets to line up along an elliptical pathAstronauts on the station are not escaping gravityThe station falls around Earth where gravity is about 90 percent of surface strength
🪐 Spacefact 166 of 200
← → to keep reading, or swipe
Tags: orbits, speed, physics
Orbiting low means moving fast: the short answers
- Where does this come from, and can I check it?
- At 400 kilometres altitude a satellite needs nearly 8 kilometres a second. The figure is taken from NASA Glenn, 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 space fact?
- Yes. It sits on the Space 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.