When it was formally opened on October 8, 1900, [President] Hazard could report that it housed "a 12" refractor with micrometer, polarizing photometer, and star and sun spectroscopes. A Rowland concave grating spectroscope, of 6' focus, with its accompanying heliostat, is set up in a room capable of being darkened completely. The library is a beautiful room, and the dome by Warner and Swasey is all that it should be."When the observatory opened October 8, 1900, Professor Whiting became its first director and the College received "congratulatory letters from famous women astronomers in Europe." At the time Professor Whiting described it as "the finest student observatory in the country." The benefactor was heavily involved in the design of the facility, including the choice of white marble, and the selection of equipment. She also had strong opinions about the floor covering to be placed in the laboratory saying "it will be good for the girls to put their feet on an India rug." Soon after completion of the observatory, Professor Whiting began exploring plans for an expansion and went back to Mrs. Whitin, as she wrote in the trustee's obituary, which appeared in "The Wellesley College News.""I knew from the first that it was not large enough for the kind of work we wished to do, and that the nearest college residence hall was too far off for the astronomical staff to be present for the nightly vigil with the stars. Whitin herself soon perceived this and of her own initiative began to think of an Observatory House, and an enlargement to the Observatory itself. The beauty and costliness of what was already done seemed difficult to match. Various compromise building materials for the addition were discussed, but after many consultations with the architect, she declared that "marble and copper were good enough," and by 1906 the observatory was doubled with increased equipment, and a house placed beside it, completing a harmonious group, and itself a lovely specimen of domestic architecture." Whitin Observatory strategic events, according to Wellesley College archives, follow. In addition to her efforts at the College, Whitin was a board member, and generous supporter, of the Baldwinsville Hospital for the Feeble Minded, for which she built a large school building, as well as the Hospital for the Insane in Worcester, Massachusetts. Sarah Elizabeth Whitin remained an active Wellesley Trustee until her illness the last two years of her life. She died on December 26, 1917.