North Korea's nuclear tests are getting more powerful

Story highlights

  • North Korea conducted its fifth nuclear test Friday
  • Tests over the years reflect the North's desire to increase its military capabilities

(CNN)Ten years, five nuclear tests, and they appear to be getting stronger.

North Korea claimed to have detonated a nuclear warhead Friday.
    At an estimated 10 kilotons, it's thought to be the most powerful explosion yet.

    #1 October 6, 2006

    U.S. intelligence estimated the first North Korean test, in October 2006, produced an explosion equal to less than 1 kiloton or the equivalent of under 1,000 tons of TNT.
    The low yield was a fraction of the size of the bombs the United States dropped on Japan at the end of World War II.
    However, the test reflected the country's desire to advance its weapons program in defiance of the international community and its closest regional ally, China.

    #2 May 25, 2009

    North Korea announced it had tested a nuclear weapon in an underground explosion, a little more than an hour after the U.S. Geological Survey reported a magnitude 4.7 seismic disturbance.
    In 2012, National Intelligence Director James Clapper told a Senate committee this test was believed to have been about 2 kilotons.
    At the time, analysts concluded that North Korea's nuclear arms program was not a major security threat.

    #3 February 12, 2013

    This was the first test carried out under new North Korean leader, Kim Jong Un.
    State media reported that a smaller, lighter device was used, but it had greater explosive force than previous tests -- perhaps around 6 to 7 kilotons, according to South Korea.
    Global leaders condemned the attack, and analysts predicted that it would be years before the North possessed the technology to deliver a nuclear warhead on a missile.

    #4 January 6, 2016

    North Korea claims to have tested a hydrogen bomb, though the US and others weren't so sure.
    The test occurred deep underground, making it hard to monitor radiation to determine what type of weapon was used. The explosive yield was thought to be 4 to 6 kilotons.
    In a statement read on state TV, Kim called it a "spectacular success," that would make "make the world ... look up to our strong nuclear country."

    #5 September 9, 2016

    The latest nuclear test by North Korea is estimated to produced a blast equivalent to 10 kilotons -- twice the power of the country's last test, according to Korea's Meteorological Administration.
    The U.S. Geological Survey (USGS) reported a 5.3 magnitude earthquake in North Korea, but later termed it an explosion. The event produced tremors at a depth of 0 kilometers, 18 kilometers (11 miles) east-northeast of Sungjibaeham, North Korea.