Lowell (Martian crater) Lowell (Martian crater) The Lowell Crater is a large impact crater on Aonia Terra in the Thaumasia quadrangle of Mars. The crater is about 203 kilometers (127 miles) in diameter. Lowell Crater has a ring of mountains on its floor which gives it a sort of bull's eye appearance. Its nearby features include the craters Slipher to the north, Douglass to the east, and Coblentz to the southwest, the small mountain Aonia Mons to the west, and Aonia Planum to the southeast. Lowell Crater is named for Percival Lowell who built the Lowell Observatory in Flagstaff, Arizona, in 1894, and
William Lowell Putnam the Observatory staff. Putnam, however, had to make the final decision on the matter and he was the one to tell See that he had been dismissed. When Lowell returned to work in 1901, Putnam resumed his role as the financial and legal power behind the Observatory. He also continued his other business in Boston and New York City. When Lowell died in 1916, Putnam was placed in charge of investing Lowell's estate for the Observatory. Putnam died in June 1923, aged around 61, during Constance Lowell's attempt to contest Percival's will. Constance Lowell later asked William's son, Augustus, to