SLIPHER; Vesto M.; 1875-1969; USA

Having managed all his career at Lowell Observatory (he directed it from 1916 to 1952), Slipher observed the planets in infrared and found numerous molecules in their atmospheres. He proved that some nebula were reflecting light with dust and used deep photographic exposures (as long as 80 hours) to obtain radial velocity of galaxies (the first redshifts); these first measurements served HUBBLE for his cosmological work.