Valentinus Otho or Valentin Otto (born around 1550 possibly in Magdeburg – April 8, 1603 in Prag) was a German mathematician and astronomer.
In 1573 he came to Wittenberg, proposing to Johannes Praetorius an approximation of Pi as .
In 1575 he supported Georg Joachim Rheticus in his trigonometric tables. The next year they went to Kaschau in Hungary where Rheticus died. Thus, Otho inherited the De revolutionibus manuscript of Nicolaus Copernicus that Rheticus had published in 1543 in Nuremberg.
Otho became Professor for astronomy in Wittenberg, but when the rulers of Saxony did not support the tables, he moved to Heidelberg where Elector Friedrich IV sponsored the '’Opus Palatinum de Triangulis’’ in 1596.
Otho (/ˈoʊθoʊ/; Latin: Marcus Salvius Otho Caesar Augustus; 28 April 32 – 16 April 69), was Roman Emperor for three months, from 15 January to 16 April 69. He was the second emperor of the Year of the Four Emperors.
Otho belonged to an ancient and noble Etruscan family, descended from the princes of Etruria and settled at Ferentinum (modern Ferento, near Viterbo) in Etruria.
The future Emperor appears first as one of the most reckless and extravagant of the young nobles who surrounded Nero. This friendship was brought to an end in 58 AD because of his wife, the noblewoman Poppaea Sabina. Otho introduced his beautiful wife to the Emperor upon Poppaea's insistence, who then began an affair that would eventually lead to her premature death. After securely establishing this position as his mistress, she divorced Otho and had the Emperor send him away as governor to the remote province of Lusitania (which is now parts of both modern Portugal and Extremadura, Spain).
Otho may refer to: