Astronauts are taller upon return to Earth

You must have read this little astronomy tidbit on one of our Astronomy facts pages:

An Astronaut can be up to 2 inches taller returning from space. The cartilage disks in the spine expand in the absence of gravity.

This is an effect of microgravity (when gravity is very little or none.) Gravity is what keeps us on the ground! Our spines, when not being compressed by gravity, are free to expand, thus making us taller. This is not only true for astronauts in space, but also us poor ordinary folks when we sleep! Why? Because the less pull there is by G forces, the happier our spine is to grow. So, it can be said that the more you sleep, the taller you may become!

All of us have experienced The G Force. Nope, it’s neither a new Playstation game, nor a summer Hollywood blockbuster starring Lindsey Lohan! It’s a great gravitational force present all around us. Notice how our stomach feels funny when we’re on a roller coaster or even a regular fun ride? That’s the G Force in action!

What is the cartilage disk, you may wonder, and how amazing that it can make one taller, eh? A cartilage disk is like a protecting cushion between bones where the bones meet each other. The cartilage disk we’re talking about here is the one in our spine or what we generally know as our backbone. Our backbone is the one that is separated by spinal discs and holds the spinal cord in place.

But here’s the catch: neither the Astronaut’s, nor a sleeping beauty’s spine continues to remain taller indefinitely. As soon as the astronaut returns to Earth, his or her height gradually returns to normal. The same is the case with us: When we wake up and stand upright or go about our daily business, our height comes down to earth, so to speak!

References: Microgravity et al.