Barack Obama plans to open his White House doors to the public on his first full day of his US presidency, Jan. 21. Obama aides on Friday announced plans to have an open house at his new home at 1600 Pennsylvania Ave. The idea is to keep Obama's administration the "most open and accessible" in history by inviting hundreds of supporters inside and encouraging them to stay involved. President Bill Clinton had a similar event after his 1993 inauguration, inviting some 2,000 citizens selected by lottery to a receiving line in the Diplomatic Reception Room on Jan. 21. Tickets this year are limited and interested residents can sign up on Obama's inauguration Web site, PIC2009.org.