1932 February - James Chadwick discovers the neutron. More » 1960 February 13 - First nuclear test by France, Sahara desert. More » 1961 February 1 - U.S. launches Minuteman I missile. 1967 February 14 - Treaty of Tlatelolco signed. More » 1998 February 24 - France's National Assembly votes unanimously to ratify the CTBT. More> 2013 February 12 - North Korea conducts third nuclear test. The device's yield is estimated at 8-10 kilotons.