U.S. Smithsonian museums, National Zoo close doors due to gov't shutdown

People stand in front of the closed doors of the Smithsonian Institution Building's visitor center in Washington D.C., the United States, on Jan. 2, 2019.?The 19 Smithsonian museums and the National Zoo in Washington D.C. closed their doors on Wednesday as the partial U.S. government shutdown dragged on.?(Xinhua/Liu Jie)