px|image_size caption doctoral_advisor death_date death_place work_institution birth_place nationality notable_students field birth_date image article_title name alma_mater
250px erhard weigel philipp müller 20 march 1699 jena university of jena weiden in der oberpfalz german gottfried wilhelm leibniz mathematician , astronomer and philosopher 16 december 1625 erhardweigel.jpg erhard weigel
 erhard weigel university of leipzig
erhard weigel

erhard weigel -lrb- december 16 , 1625 -- march 21 , 1699 -rrb- was a german mathematician , astronomer and philosopher .
he earned his ph.d. from the university of leipzig .
from 1653 until his death he was professor of mathematics at jena university .
he was the teacher of leibniz in 1663 , and other notable students .
he also worked to make science more widely accessible to the public , and what would today be considered a populariser of science .
through leibniz , weigel is the intellectual forefather of a long tradition of mathematicians that connects a great number of professionals to this day .
the mathematics genealogy project lists more than 50,000 `` descendants '' of weigel 's , including lagrange , euler , poisson and several fields medalists .
he concurred with jakob ellrod 's `` mittel-calendar '' , and with the advocacy of leibniz and others , that the date of easter should be based on the astronomical measurement of the spring equinox and the next full moon .
he followed jakob ellrod to the imperial diet in regensburg to advocate the use of the mittel-calendar or new gregorian calendar .
the crater weigel on the moon is named after him .
in 1999 a colloquium was held in jena on the 300th anniversary of his death .
