Today is Saturday, Feb. 23, the 54th day of 2013. There are 311 days left in the year. On Feb. 23, 1863, British explorers John H. Speke and James A. Grant announced they had found the source of the Nile River to be Lake Victoria. This finding was disputed by Speke's colleague, Richard F. Burton, who felt that proof was lacking, but the lake is now considered the Nile's source. In 1836, the siege of the Alamo began in San Antonio, Texas. In 1848, the sixth president of the United States, John Quincy Adams, died in Washington, D.C., at age 80. In 1861, President-elect Abraham Lincoln arrived secretly in Washington to take office, following word of a possible assassination plot in Baltimore. In 1870, Mississippi was readmitted to the Union. In 1903, President Theodore Roosevelt signed an agreement with Cuba to lease the area around Guantanamo Bay to the United States. In 1927, President Calvin Coolidge signed a bill creating the Federal Radio Commission, forerunner of the Federal Communications Commission. In 1945, during World War II, U.S. Marines on Iwo Jima captured Mount Suribachi. In 1954, the first mass inoculation of children against polio with the Salk vaccine began in Pittsburgh. In 1965, film comedian Stan Laurel, 74, died in Santa Monica, Calif. In 1970, Guyana became a republic within the Commonwealth of Nations. In 1981, an attempted coup began in Spain as 200 members of the Civil Guard invaded Parliament, taking lawmakers hostage. However, the attempt collapsed 18 hours later. In 1992, the XVI Winter Olympic Games ended in Albertville, France. Ten years ago: In West Warwick, R.I., relatives of the victims of a deadly nightclub fire were allowed to walk up to the charred rubble to pray and say goodbye. Norah Jones won five Grammys, including album and record of the year. Five years ago: Defense Secretary Robert Gates and other U.S. officials held daylong meetings with Australian leaders in Canberra. Former United Auto Workers president Douglas A. Fraser died in Southfield, Mich., at age 91. One year ago: President Barack Obama, speaking in Miami, sought to confront public anxiety over rising gasoline prices as he promoted the expansion of domestic oil and gas exploration, as well as the development of new forms of energy. Former U.N. secretary-general Kofi Annan was appointed the joint United Nations-Arab League envoy on the Syrian crisis. Today's Birthdays: Actor Peter Fonda is 73. Pro and College Football Hall of Famer Fred Biletnikoff is 70. Author John Sandford is 69. Singer-musician Johnny Winter is 69. Country-rock musician Rusty Young is 67. Actress Patricia Richardson is 62. Rock musician Brad Whitford (Aerosmith) is 61. Singer Howard Jones is 58. Rock musician Michael Wilton (Queensryche) is 51. Country singer Dusty Drake is 49. Actress Kristin Davis is 48. Tennis player Helena Sukova is 48. Actor Marc Price is 45. Actress Niecy Nash is 43. Rock musician Jeff Beres (Sister Hazel) is 42. Country singer Steve Holy is 41. Rock musician Lasse (loss) Johansson (The Cardigans) is 40. Actress Kelly Macdonald is 37. Actress Emily Blunt is 30. Actor Aziz Ansari is 30. Actress Dakota Fanning is 19. Thought for Today: "Never doubt that a small, group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has." - Margaret Mead, American anthropologist (1901-1978). Above Advance for Use Saturday, Feb. 23 Copyright 2013, The Associated Press.