What optical device is the Dutch scientist, after whom the lunar crater Jansen is named, credited for?
Zacharias Janssen Zacharias Janssen (also Zacharias Jansen or Sacharias Jansen) (1585 – pre-1632) was a Dutch spectacle-maker from Middelburg associated with the invention of the first optical telescope. Janssen is sometimes also credited for inventing the first truly compound microscope. However, the origin of the microscope, just like the origin of the telescope, is a matter of debate.
Kundt (crater) Kundt is a small, bowl-shaped lunar impact crater in the northern section of the Mare Nubium, and is named after the German physicist August Kundt. It has a raised rim and is not significantly worn due to impact erosion. This crater lies part way between Guericke to the west and Davy in the east.