Everyone seems to talk about the weather, and it certainly has a huge effect on our daily lives. 

Weather is a result of day-to-day changes in the atmosphere.  Changes in temperature, wind, moisture, and pressure combine to create weather.  We describe it by talking about sunshine, cloud cover, temperature, wind, and precipitation. 

Meteorologists spend their time reporting the weather and trying to accurately predict weather conditions.  So many factors interact to create weather that it’s often difficult to make accurate predictions.

Weather is the greatest cause of Space Shuttle launch delays. Sometimes a few clouds or light rain can delay a launch. NASA is very safety conscious when considering launch conditions.

It’s dangerous to launch the Shuttle in a thunderstorm. Lightning striking the Shuttle could cause many problems. The electronic equipment on board could shut down. The Shuttle could lose control and crash. What about just a cloudy day? The risk of lightning still exists, but it’s a different type of lightning.

The Space Shuttle can trigger lightning while passing through clouds. An incident actually happened 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.

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

Precipitation is also dangerous to the Shuttle. The Shuttle is covered with tiles that keep it from overheating as it bumps into air particles. If the tiles get wet during a launch, they could buckle in the freezing temperatures of space and break up under high heat during the return to Earth.

Preventing launch delays is important. NASA is learning more about clouds and lightning to help launch crews become better at predicting bad weather so launches will have fewer delays.