* Astronomy

Per Teodor Cleve (10 February 1840 - 18 June 1905) was a Swedish chemist and geologist.
In 1874, he concluded that didymium was in fact two elements, now known as neodymium and praseodymium. He also discovered the elements holmium and thulium in 1879.
The mineral cleveite was named in 1878 by the geologist and explorer Adolf Erik Nordenskiöld in his honour.
Read more