An eyeglasses prescription for Christiaan Huygens after 330 years

Christiaan Huygens built excellent lenses in the 17th century, but his telescopes lacked sharpness in comparison with what was possible at that time. In a recent study, Dr. Alex Pietrow, researcher at the Leibniz Institute for Astrophysics Potsdam (AIP), investigated Huygens' calculations and has concluded that the Dutch astronomer and mathematician was probably near-sighted and would have needed eyeglasses to improve his telescopes.