[Abu Rayhan al-Biruni][1] (973 – after 1050) was an Iranian polymath,  physicist, astronomer, natural sciences, historian, chronologist and linguist. One of the best his achievements is a method proposed and used by him to estimate the radius and circumference of the Earth almost 1000 years ago.

He was also inventor of minutes and seconds of time.

[![enter image description here][2]][2]


  [1]: https://en.wikipedia.org/wiki/Al-Biruni
  [2]: https://i.sstatic.net/3SfiX.png