Neil deGrasse Tyson

Neil deGrasse Tyson @neiltyson

@eastcstwestcst @dmaoutdoors The lunar month, the solar year, and the Cesium 133 Atomic Clock come from the physics of the universe, and so are not contrived by humans. — PolitiTweet.org

Neil deGrasse Tyson @neiltyson

@X1_Atomic @eastcstwestcst @dmaoutdoors A fortnight, a week, an hour, a second — these all arbitrary human constructs. The others derive from astronomical or physical entities. — PolitiTweet.org