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

The United States switched off deliberate signal degradation, cutting civilian error from about 100 metres to 20. The figure is taken from National Coordination Office for Space-Based PNT, 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.

Mondo Knows Facts

GPS accuracy improved overnight in May 2000

The United States switched off deliberate signal degradation, cutting civilian error from about 100 metres to 20 Selective availability added timing noise to the civilian signal so that military receivers kept an advantage. President Clinton ordered it discontinued, and the change took effect at midnight on 1 May 2000. Consumer navigation devices that had been toys became genuinely useful, and the market grew quickly afterwards. It sits in Mondo's technology collection, one of 200 facts that each trace back to the reference below.

Where this comes from

National Coordination Office for Space-Based PNT

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Tags: gps, navigation, policy

GPS accuracy improved overnight in May 2000: the short answers

Where does this come from, and can I check it?: The United States switched off deliberate signal degradation, cutting civilian error from about 100 metres to 20. The figure is taken from National Coordination Office for Space-Based PNT, 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.