## Do a Sanity Test

"Doing a sanity test" is rocket science parlance for simply asking, "Does this make sense?"

Rocket scientists can become myopic in their work. (After all, most of them are near-sighted and have to wear thick glasses.) They get caught up in their equations, calculations, and computer simulations. They can become so involved in the mathematical details and technical minutiae that they lose sight of the big picture—like an instrument-rated pilot glued to his gauges who never looks out the window to see where he's going or if he's about to collide with another aircraft.

When a rocket scientist does a sanity test, he's pinching himself back into reality and asking if what he has done adds up. One of the challenges that rocket scientists experience is that they live in a world of mathematical symbols that they manipulate in order to understand how the rocket will perform in space. These symbols are shorthand for the laws of the universe. By writing equations and sorting the symbols by the rules of algebra, the rocket scientist can predict how high and how fast the rocket will go and when it will get to its destination, which could be as far away as Pluto—4 billion miles from the sun. For example, when the Voyager spacecraft arrived at Neptune (which is nearly as distant as Pluto), the error in the spacecraft's arrival time was only fourteen seconds out of a total trip time of nearly twelve years.

So the laws of celestial mechanics are extremely precise.

But there is a downside to this world of symbols: The slightest error in addition or algebra makes the entire analysis wrong—completely meaningless and without value. The same thing applies to the rocket scientist's dependence on the computer: one wrong keystroke and everything is wrong. Garbage in, garbage out!

Thus, rocket scientists have to constantly look up from their desks or computer screens and ask, "Does this make any sense?"

The mathematics that rocket scientists wield is the key that grants them access to the secrets of the universe. Mishandled, it can produce delusions and disaster.

Indeed, sanity tests need to be performed regularly and not just by rocket scientists.

## Post a comment