MILLEDGEVILLE — Pop Quiz: When was the last time you’ve had to deal with a leak? Chances are it wasn’t too long ago. Perhaps it was a toilet with a trickle, a hose with a hole or — the horrors — a diaper with a drip. Either way, it probably wasn’t pleasant, cost you money to fix or elbow grease to repair or resulted in nausea during the cleanup.

As on Earth, so on the International Space Station.

Wherever fluids are contained, leaks happen. And it’s quite a different issue in Earth orbit. Lucky for us down here, liquids tend to follow gravity downward where we can eventually clean them up somehow. No such luck in space. Liquids in the ISS coalesce into spherical blobs that float wherever even the slightest air current takes them. And yes, that may be your lungs as you inhale. Nope, not funny at all.

Astronauts try to contain spilled liquids by allowing the floating droplets to make contact with a solid material where most will readily attach themselves. Or they break out the vacuum hose and suck up the mess as quickly as possible, before it gets into electronic equipment and really wreaks havoc.

If the leak is outside in the vacuum of space, well, it’s pretty much a lost cause. Basic fluid physics dictates that the lower the ambient pressure is the quicker a liquid boils (that’s why water boils at less than 212ºF at high altitudes). In space with next to zero pressure, liquids either freeze or flash into gas in an instant, and they’re no longer retrievable.

The residents of the ISS are dealing with ammonia coolant leak right now. It’s not news — there has been a leak in one of the radiators for a long time, but sensors recently indicated a four-fold increase in fluid loss, so either the leak got bigger or — most likely — there’s a new leak in the system. With near-invisible tiny micrometeorites peppering the ISS one of those tiny specks of dust is bound to hit a coolant tube and punch a minuscule hole into it. Fortunately they spell redundancy with capital letters on the ISS, so there is a spare that they can hook up and see whether that fixes the leak or whether it’s in another component of the coolant system. If that system looses too much ammonia it will shut down, which means less power and thus fewer experiments and research.

Since there are no plumbers in outer space, the astronauts have to fix the leak themselves. Good thing they’ve all been trained in those kinds of maintenance tasks, even if it involves a spacewalk.

Don’t forget the duct tape, folks.

Learn more about how the ISS stays at the right temperature at http://science.nasa.gov/science-news/science-at-nasa/2001/ast21mar_1/



Beate Czogalla is the Professor of Theater Design in the Department of Theatre and Dance at Georgia College & State University. She has had a lifelong interest in space exploration and has been a Solar System Ambassador for the Jet Propulsion Laboratory/ NASA for many years. She can be reached at   our_space2@yahoo.com