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.
Bunsen (crater) Bunsen is a lunar crater that lies near the northwestern limb of the Moon. It is located to the west of the Oceanus Procellarum and the crater von Braun. To the southeast is the crater Lavoisier, and to the northeast lies Gerard. Northwest of Bunsen, on the far side of the Moon, is McLaughlin. Due to its position this crater appears foreshortened when viewed from the Earth, and its visibility is affected by libration.