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: January 2014

loading photos...
  1. Southern stargazing

    Stars, galaxies and nebulas dot the skies over the European Southern Observatory's La Silla Paranal Observatory in Chile, in a picture released on Jan. 7. This image also shows three of the four movable units that feed light into the Very Large Telescope Interferometer, the world's most advanced optical instrument. Combining to form one larger telescope, they are greater than the sum of their parts: They reveal details that would otherwise be visible only through a telescope as large as the distance between them. (Y. Beletsky / ESO) Back to slideshow navigation
  2. A balloon's view

    Cameras captured the Grandville High School RoboDawgs' balloon floating through Earth's upper atmosphere during its ascent on Dec. 28, 2013. The Grandville RoboDawgs’ first winter balloon launch reached an estimated altitude of 130,000 feet, or about 25 miles, according to coaches Mike Evele and Doug Hepfer. It skyrocketed past the team’s previous 100,000-feet record set in June. The RoboDawgs started with just one robotics team in 1998, but they've grown to support more than 30 teams at public schools in Grandville, Mich. (Kyle Moroney / AP) Back to slideshow navigation
  3. Spacemen at work

    Russian cosmonauts Oleg Kotov, right, and Sergey Ryazanskiy perform maintenance on the International Space Station on Jan. 27. During the six-hour, eight-minute spacewalk, Kotov and Ryazanskiy completed the installation of a pair of high-fidelity cameras that experienced connectivity issues during a Dec. 27 spacewalk. The cosmonauts also retrieved scientific gear outside the station's Russian segment. (NASA) Back to slideshow navigation
  4. Special delivery

    The International Space Station's Canadian-built robotic arm moves toward Orbital Sciences Corp.'s Cygnus autonomous cargo craft as it approaches the station for a Jan. 12 delivery. The mountains below are the southwestern Alps. (NASA) Back to slideshow navigation
  5. Accidental art

    A piece of art? A time-lapse photo? A flickering light show? At first glance, this image looks nothing like the images we're used to seeing from the Hubble Space Telescope. But it's a genuine Hubble frame that was released on Jan. 27. Hubble's team suspects that the telescope's Fine Guidance System locked onto a bad guide star, potentially a double star or binary. This caused an error in the tracking system, resulting in a remarkable picture of brightly colored stellar streaks. The prominent red streaks are from stars in the globular cluster NGC 288. (NASA / ESA) Back to slideshow navigation
  6. Supersonic test flight

    A camera looking back over Virgin Galactic's SpaceShipTwo's fuselage shows the rocket burn with a Mojave Desert vista in the background during a test flight of the rocket plane on Jan. 10. Cameras were mounted on the exterior of SpaceShipTwo as well as its carrier airplane, WhiteKnightTwo, to monitor the rocket engine's performance. The test was aimed at setting the stage for honest-to-goodness flights into outer space later this year, and eventual commercial space tours.

    More about SpaceShipTwo on PhotoBlog (Virgin Galactic) Back to slideshow navigation
  7. Red lagoon

    The VLT Survey Telescope at the European Southern Observatory's Paranal Observatory in Chile captured this richly detailed new image of the Lagoon Nebula, released on Jan. 22. This giant cloud of gas and dust is creating intensely bright young stars, and is home to young stellar clusters. This image is a tiny part of just one of 11 public surveys of the sky now in progress using ESO telescopes. (ESO/VPHAS team) Back to slideshow navigation
  8. Fire on the mountain

    This image provided by NASA shows a satellite view of smoke from the Colby Fire, taken by the Multi-angle Imaging SpectroRadiometer aboard NASA's Terra spacecraft as it passed over Southern California on Jan. 16. The fire burned more than 1,863 acres and forced the evacuation of 3,700 people. (NASA via AP) Back to slideshow navigation
  9. Where stars are born

    An image captured by NASA's Spitzer Space Telescope shows the Orion Nebula, an immense stellar nursery some 1,500 light-years away. This false-color infrared view, released on Jan. 15, spans about 40 light-years across the region. The brightest portion of the nebula is centered on Orion's young, massive, hot stars, known as the Trapezium Cluster. But Spitzer also can detect stars still in the process of formation, seen here in red hues. (NASA / JPL-Caltech) Back to slideshow navigation
  10. Cygnus takes flight

    Orbital Sciences Corp.'s Antares rocket rises from NASA's Wallops Flight Facility on Wallops Island, Va, on Jan. 9. The rocket sent Orbital's Cygnus cargo capsule on its first official resupply mission to the International Space Station. (Chris Perry / NASA) Back to slideshow navigation
  11. A long, long time ago...

    This long-exposure picture from the Hubble Space Telescope, released Jan. 8, is the deepest image ever made of any cluster of galaxies. The cluster known as Abell 2744 appears in the foreground. It contains several hundred galaxies as they looked 3.5 billion years ago. Abell 2744 acts as a gravitational lens to warp space, brightening and magnifying images of nearly 3,000 distant background galaxies. The more distant galaxies appear as they did more than 12 billion years ago, not long after the Big Bang. (NASA / NASA via AFP - Getty Images) Back to slideshow navigation
  12. Frosty halo

    Sun dogs are bright spots that appear in the sky around the sun when light is refracted through ice crystals in the atmosphere. These sun dogs appeared on Jan. 5 amid brutally cold temperatures along Highway 83, north of Bismarck, N.D. The temperature was about 22 degrees below zero Fahrenheit, with a 50-below-zero wind chill.

    Slideshow: The Year in Space (Brian Peterson / The Bismarck Tribune via AP) 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