Marc Amsler honor in ophthalmology. Amsler was professor and chief of the Zurich Eye Clinic until 1961. His successor was Rudolf Witmer. He is best known for the Amsler grid test. The Amsler grid was an improvement over the initial work done by the ophthalmologist Edmond Landolt. The grid tests the function of the macula, a part of the retina, so that macular degeneration can be identified. He also contributed to the progress in the understanding of uveitis. Furthermore, he published works on keratoconus. In 1951, Dr. Amsler performed the first corneal transplantation at the Zurich Eye clinic. Marc Amsler Marc Amsler
Grid fin The grid fin development effort is a part of the SpaceX reusable launch system development program that has been underway since 2012. The first hypersonic flight test with grid fins was in February 2015, and grid fins were subsequently used on all reusable Falcon 9 experimental test landings and, eventually, after December 2015, an increasing number of successful first stage landings and recoveries. Iteration on the design of the Falcon 9 grid fins continued into 2017. SpaceX CEO Elon Musk announced in early 2017 that a new version of the Falcon 9 grid fins would improve reusability for the company's