By
updated 4/13/2012 3:26:08 PM ET 2012-04-13T19:26:08

It really is rocket science, and it really is hard. North Korea proved that again.

The giant explosion that gets a rocket off the ground isn't that complicated. The superhot, superfast exhaust from that giant fire is funneled in a way that shoots the rocket upward. North Korea's Unha-3 rocket combines two liquid propellants — hydrazine and nitric acid — that ignite when mixed, space experts say.

That's the easy part.

Controlling that reaction and going where you want, when you want — that's where engineers earn their money and ulcers. And it's where past rockets and spaceships have ended in spectacular and sometimes deadly failures.

"Anybody can make something go boom. Controlling it is hard," said former NASA associate administrator Scott Pace, director of space policy at George Washington University.

All that power has to be confined by metal and controlled by electronics. It takes the power of about a ton of TNT just to get 60 pounds into orbit at almost 18,000 mph (28,800 kiloeters per hour). One tiny mistake, one mismatch in devices, one miscommunication, one bubble, and boom.

In 1986, the fiery power of the space shuttle Challenger burned through an O-ring seal and seven astronauts died.

Other control problems have doomed spaceships. Aerodynamics — keeping the pointy end straight up — is key. If a rocket veers too much it just breaks apart, said Jonathan McDowell of Harvard University.

New countries launching rockets generally fail half the time, he said. John Glenn recalled how NASA's first astronauts watched in horror as an Atlas rocket blew up in front of them. More recently, private U.S. company SpaceX failed on its first three Falcon 1 launch attempts before finally succeeding. Even the normally reliable Russians couldn't get a rocket to Mars last fall because of a post-launch failure that ended up with the spaceship on board falling back to Earth.

  1. Space news from NBCNews.com
    1. KARE
      Teen's space mission fueled by social media

      Science editor Alan Boyle's blog: "Astronaut Abby" is at the controls of a social-media machine that is launching the 15-year-old from Minnesota to Kazakhstan this month for the liftoff of the International Space Station's next crew.

    2. Buzz Aldrin's vision for journey to Mars
    3. Giant black hole may be cooking up meals
    4. Watch a 'ring of fire' solar eclipse online

What doomed the North Korea rocket minutes after launch Friday isn't yet known.

Failure often comes from not putting things together right. Tens of thousands of parts have to match perfectly and talk to each other.

NASA's 2001 Mars Odyssey probe took 10,000 separate actions to go right to get there, said Scott Hubbard of Stanford University. Two years earlier, NASA mistakenly used both metric and English measuring units, dooming a $125 million Martian probe.

Former NASA deputy administrator Hans Mark said most failures are from human error. He pointed to a dropped oxygen tank that caused the near-fatal Apollo 13 explosion.

Poor communication between engineers and managers about known problems was a factor in both the 1986 and 2003 space shuttle disasters and that's a bigger issue for totalitarian societies like North Korea, Pace said.

"In many ways, the worst enemy of NASA is 'Star Trek,'" Pace said. "Captain Picard says 'engage' and the ship moves. And people think 'How hard can this be?'"

North Korea knows.

More about the North Korean failure:

© 2013 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Video: N. Korean rocket breaks apart over Yellow Sea

  1. Closed captioning of: N. Korean rocket breaks apart over Yellow Sea

    >> security council meets this morning in the wake of a failed rocket launch in north korea . incomes's chief pentagon correspondent jim miklaszewski has more.

    >> good morning, natalie. this rocket launch was a total bust from the very beginning. u.s. officials say that within 90 seconds of the launch of that rocket, it appeared to just fall apart in midair, dozens of pieces that fell harmlessly into the yellow sea , just west of the korean peninsula . now, korean officials there in the north had claimed this mission was an attempt to launch a weather satellite into space. but u.s. officials had set an alarm, this was a thinly veiled mission to test the nuclear -- or the military ability of north korea to launch a long-range missile that could ultimately reach the united states , perhaps armed with a warhead. now, this failed test is clearly a huge setback, militarily and politically, for the north korea 's new leader kim jong -il. and the fear here in washington, is that the north koreans have made indications that they were preparing for an underground nuclear test . now that this rocket has failed, the concern is that the north koreans will certainly go ahead with this underground nuclear test , if for nothing else, to save

Photos: Month in Space: April 2013

loading photos...
  1. The view from space

    This view from the International Space Station shows the sun heading toward the horizon over southwestern Australia on April 2, 2013. The space station's solar panels loom in the foreground. (Commander Chris Hadfield / CSA via AFP - Getty Images) Back to slideshow navigation
  2. Horsehead of a different color

    The Horsehead Nebula takes on an eerie glow in an infrared image from the Hubble Space Telescope. This picture, released April 21, marks the 23rd anniversary of the famous observatory's launch in 1990 aboard the space shuttle Discovery. (NASA / ESA / Hubble Heritage Team via EPA) Back to slideshow navigation
  3. Tight quarters

    Italian astronaut Luca Parmitano (right), NASA astronaut Karen Nyberg (left) and Russian cosmonaut Fyodor Yurchikhin get their picture taken inside a Soyuz capsule simulator during a training exercise at Russia's Star City complex outside Moscow on April 26. The three spacefliers are scheduled to head for the International Space Station in May. (Sergei Remezov / Reuters) Back to slideshow navigation
  4. Blazing sun

    This full-disk view of the sun was captured by NASA's Solar Dynamics Observatory on April 11, during the strongest solar flare yet seen in 2013. The colors reflect the intensity of emissions in extreme ultraviolet wavelengths. (NASA / SDO) Back to slideshow navigation
  5. Evil eye

    Mountain ridges near San Alberto in Mexico look like a reptilian eye in this view from the International Space Station. Canadian astronaut Chris Hadfield uses a different metaphor: "A Dali watch on an alligator wristband." The picture was taken on April 15 and shared via social media on April 25. (Commander Chris Hadfield / Canadian Space Agency) Back to slideshow navigation
  6. Russian rocket's red glare

    A Russian Soyuz rocket blasts away from its launch pad at the Baikonur Cosmodrome in Kazakhstan on March 29, sending NASA astronaut Chris Cassidy and Russian crewmates Pavel Vinogradov and Alexander Misurkin toward the International Space Station for their six-month orbital tour of duty. (Sergei Ilnitsky / EPA) Back to slideshow navigation
  7. Fun with rockets

    Children hold self-made rocket models during a show in front of the Peter and Paul Fortress in St. Petersburg, Russia, on April 14. The gathering was part of the festivities surrounding Cosmonautics Day on April 12. The Russian holiday marks the anniversary of Soviet cosmonaut Yuri Gagarin's historic spaceflight in 1961 - an occasion marked in other countries as "Yuri's Night." (Alexander Demianchuk / Reuters) Back to slideshow navigation
  8. Strokes in the Sahara

    Geological formations take on an alien look in a picture of the southern Sahara in Mauritania, taken on March 19 from the International Space Station and shared via social media on April 24. Canadian astronaut Chris Hadfield calls the scene "effortless natural art." (Commander Chris Hadfield / Canadian Space Agency) Back to slideshow navigation
  9. Stars in the cloud

    This glittering picture shows X-ray emissions from young sunlike stars in the "wing" of the Small Magellanic Cloud, a satellite galaxy associated with the larger Milky Way. The Small Magellanic Cloud lies about 180,000 light-years from Earth. In this April 4 picture, readings from the Chandra X-ray Observatory are shown in purple; visible light seen by the Hubble Space Telescope is in red, green, and blue; and infrared readings from the Spitzer Space Telescope are indicated in red. (NASA via Reuters) Back to slideshow navigation
  10. A blast on Mars

    This image from the high-resolution camera on NASA's Mars Reconnaissance Orbiter shows a relatively youthful crater with dark-rayed ejecta, plus a light-toned zone that extends beyond that ejecta. The picture was taken in 2009, but it was released along with other images from the High Resolution Imaging Science Experiment, or HiRISE, on April 3, 2013. Watch a video about the crater (NASA/JPL/University Of Arizona) Back to slideshow navigation
  11. A new rocket rises

    Orbital Sciences Corp.'s Antares rocket rises for the first time from its launch pad on April 21 at the Mid-Atlantic Regional Spaceport on Wallops Island, Va. This practice launch was aimed at testing the rocket for what's expected to be regular cargo deliveries to the International Space Station (Terry Zaperach / NASA Wallops via AP) Back to slideshow navigation
  12. Storm over the Middle East

    An image from NASA's Terra satellite shows a thick plume of dust blowing over the eastern Mediterranean Sea on April 1. The clouds spread over Israel, the West Bank, Cyprus and Turkey in a giant, counterclockwise arc. (NASA via AFP - Getty Images) Back to slideshow navigation
  13. Blue heaven

    A March 27 photo from the European Southern Observatory shows the bright open star cluster NGC 2547, as seen by the Wide Field Imager on the MPG/ESO 2.2-meter telescope at the La Silla Observatory in Chile. Many remote galaxies can be seen between the bright stars, far away in the background of the image. (ESO via AFP - Getty Images) Back to slideshow navigation
  14. Ready for a rocket ride

    Launch crew members check NASA astronaut Chris Cassidy's spacesuit just before his March 28 launch to the International Space Station. Russian cosmonauts Pavel Vinogradov and Alexander Misurkin joined Cassidy in a Soyuz capsule for a quick six-hour ride to the station. (Ramil Sitdikov / Ria Novosti / EPA) Back to slideshow navigation
  15. A supersonic leap

    Virgin Galactic's SpaceShipTwo lights up its rockets for the first time in flight on April 29. Afterward, the company said in a tweet that the pilots confirmed "SpaceShipTwo exceeded the speed of sound on today's flight!" The reported maximum velocity was Mach 1.2. Virgin Galactic plans to send paying passengers on suborbital space trips on a regular basis. (MarsScientific.com / Clay Center Observatory via EPA) Back to slideshow navigation
  16. Where stars are born

    An enormous stellar nursery known as W3 shines in infrared light, as shown in a March 27 image from the European Space Agency's Herschel space observatory. W3 lies about 6,200 light-years away in the Perseus Arm, one of the Milky Way galaxy's main spiral arms. In this image, low-mass stars are seen as tiny yellow dots embedded in cool red filaments. In contrast, high-mass stars emit intense radiation that heats up the gas and dust around them. Those hot regions are shown here in blue. (ESA via AFP - Getty Images) Back to slideshow navigation
  17. Crazy quilt

    The rugged landscape of Iytwelepenty/Davenport Murchison National Park in the Australian Outback is "crazily beautiful" when seen from outer space, Canadian astronaut Chris Hadfield says. Hadfield sent down this picture from the International Space Station on April 21. (Commander Chris Hadfield / Canadian Space Agency) Back to slideshow navigation
  18. A comet's glow

    Comet ISON takes on a fuzzy glow in an April 10 image from the Hubble Space Telescope. This picture was taken when the comet was 394 million miles from Earth, but Comet ISON is expected to get much closer. Some skywatchers hope it will become bright enough to rank as the "Comet of the Century." (J.-Y. Li (PSI) / NASA / ESA) Back to slideshow navigation
  1. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  2. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  3. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  4. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

Discuss:

Discussion comments

,

Most active discussions

  1. votes comments
  2. votes comments
  3. votes comments
  4. votes comments
  1. Jump to text

    It really is rocket science, and it really is ha...

  2. Jump to video

    N. Korean rocket breaks apart over ...

  3. Image: US-SPACE-ISS-AUSTRALIA
    Commander Chris Hadfield / CSA via AFP - Getty Images
    Jump to photos

    Month in Space: April 2013

  4. Jump to discussion

    North Korea faces rocket reality: Failure is an ...