Failed Shuttle Launch: It's About More Than Just Thunderstorms

NASA is hoping to launch the space shuttle Endeavour Wednesday evening. This is all if showers and thunderstorms don't force the space agency to scrub liftoff yet again.

So far there are five failed attempts. This tally may seem high, but it's not the record for the most vexed shuttle flight. No, that title belongs to two NASA missions, the STS-73 flight in 1995 and the STS-61C in 1986, both aboard the shuttle Columbia.

In order for Endeavour to set a record, the shuttle will have to miss two more launch attempts and lift off on the 8th try to take the title.

Now lately...all of the talk has been about thunderstorms. But it's actually much more complicated than that.

Weather is THE greatest cause of space shuttle launch delays. Sometimes even just a few clouds or light rain can delay a launch.

First, it's very dangerous to launch the shuttle in a thunderstorm. If lightning strikes the shuttle, it can cause many problems. The electronic equipment on board could shut down. Then the shuttle could lose control and crash.

But what about just a cloudy day? Well, there's still a risk of lightning, but it's a different type of lightning. A space shuttle can trigger lightning while passing through clouds. It actually happened back in 1969 with the Apollo 12 launch. The spacecraft triggered two lightning strikes. There was NO NATURAL lightning present, and the shuttle's backup systems allowed the flight to continue safely.

Because of this, NASA looks at the thickness of clouds to help determine whether lightning could be triggered.

Next is precipitation. It too is dangerous. A space shuttle is covered with tiles, which keep it from overheating as it bumps into air particles. If these tiles get wet during a launch, the tiles could buckle in the freezing temperatures of space and break up under high heat during the return to Earth.

Now finally...just imagine for a moment all of the forecasting that must happen. Accurate predictions are truly a must.