sentences:  The idea for the Museum of Modern Art was developed in 1929 primarily by Abby Aldrich Rockefeller (wife of John D. Rockefeller, Jr.) and two of her friends, Lillie P. Bliss and Mary Quinn Sullivan.They became known variously as "the Ladies" or "the adamantine ladies".They rented modest quarters for the new museum in the Heckscher Building at 730 Fifth Avenue in Manhattan, and it opened to the public on November 7, 1929, nine days after the Wall Street Crash.