Why Kids Think It's Cool:
Where should we begin? First you get to fly on the world's largest bottle rocket from planet to planet, where you meet all kinds of aliens. Remember, at the age when kids want to be astronauts when they grow up, they still haven't seen movies where aliens rip out of your chest or hunt you for sport. As far as little kids are concerned, aliens are fun and playful, like dolphins in outer space.
Dolphins who own ray guns.
Even if your child is a bit more practical and understands that being an astronaut is not the same as being a Jedi, all they've ever seen astronauts do is float around in anti-gravity, doing somersaults and squirting their food out of tubes before chasing it down and eating it mid-air. Astronauts are professional food fighters, and as we all know, they eat nothing but freeze-dried ice cream and Tang. That kind of nutrition gives them energy to do their jobs, like when they fly to the moon and perform vital scientific experiments such as golf, and jumping around like they're on a great big bouncy castle.
Why the Job Actually Sucks:
Because you need a Ph.D. just to do an astronaut's dry cleaning. To be an actual astronaut, a person has to be two-thirds Stephen Hawking, and one-third someone who has perfect vision and awesome hand-eye coordination. To make sure they have the right guy, NASA subjects their astronauts to an endless series of grueling tests.
Before they go to the celestial trampoline we call the moon, astronauts spend about ten years keeping themselves in peak physical condition while essentially taking the SAT every single day. Even if your kid's some rare breed of super genius who enjoys both tests and pushups, it's still not all it's cracked up to be. To give your kid an idea of what an astronaut's job is truly like, do the following:
Step 1: Go buy a van - preferably a 1976 Peugeot.
Step 2: Have the owner's manual translated into Russian.
Step 3: Tell your child to pretend the van is a space station, and that his or her assignment is to rotate the tires.
Step 4: Push the van to the bottom of a swimming pool. Hand your child the translated owner's manual, a toolbox and a balloon full of air.
For more careers that will only disappoint you check out The 5 Most Overrated Jobs Of All-Time. Or, get paranoid reading 6 Emails You Get When Your Company Is About to Go Under.