#OnThisDay in 1930, Clyde Tombaugh discovered the ninth planet, Pluto, at Lowell Observatory. #lowel
#OnThisDay in 1930, Clyde Tombaugh discovered the ninth planet, Pluto, at Lowell Observatory. #lowellobservatory #lowell #observatory #FlagstaffAZ #flagstaff #arizona #marshill #clydetombaugh #pluto #science #space #astronomy #tbt #throwbackthursday -- source link
#lowell#marshill#observatory#throwbackthursday#flagstaff#science#clydetombaugh#lowellobservatory#arizona#flagstaffaz#astronomy#onthisday