(Submitted April 11, 1997)
My first graders want to know, How do astronauts go to the bathroom in space?
I think the potty chair is in place. Is this correct?
We have come up with a number of answers to your question. We will
let you, as the professional teacher, decide which is appropriate for
your classroom and what is best left to the teachers lounge.
I. The Official NASA pages:
A. There is a nice space shuttle web page at:
Digging in there I found a Q&A Web page. Here's what it says:
6. How do you take a bath, brush your teeth, and go to the bathroom in space?
We do not have a bath or shower on the Shuttle, so we just wash
off with wet washcloths, using soaps that you don't have to
rinse off. When we brush our teeth, we can either swallow the
toothpaste or spit it into a washcloth. Designing a toilet for
zero-gravity is tougher. We use air flow to make the urine or
feces go where we want, since gravity will not do it for us.
You have to be more careful and think about what you are doing
with the toilet in the Shuttle.
B. Another colleague pointed out that Johnson Space Center is the home of
the astronauts, and they have some web pages dealing with this issue too.
(We really know little more than you do about the astronaut
program -- but they do.)
Their home page at:
has links for KIDS, EDUCATORS, and more.
I went to their page:
and this is what I found:
This used to be under the old FAQ at Spacelink. It has since been removed.
4. HOW DO ASTRONAUTS GO TO THE BATHROOM AND TAKE CARE OF OTHER PERSONAL
Each Space Shuttle has a toilet that can be used by both men
and women. Designed to be as much as possible like those on Earth,
the units use flowing air instead of water to move waste through
Solid wastes are compressed and stored on-board, and then
removed after landing. Waste water is vented to space, although
future systems may recycle it. The air is filtered to remove odor
and bacteria and then returned to the cabin.
Astronauts brush their teeth just like they do on Earth.
There is no shower on the Shuttle, so astronauts must make do with
sponge baths until they return home.
The toilet that was first flown aboard STS-54 is completely new in
design and offers new and improved features:
The new toilet features better hygiene, larger storage capacity,
greater dependability, and an overall cost savings in maintenance.
-The previous model had a 14-day capacity for storage of waste
material. The new model has an unlimited storage capacity.
-The new model features a cylinder system where a plastic bag is
placed in the toilet before use. The bag is then sealed and is
forced to the bottom of the cylinder after each use by a plunger
attached to a lever. A new bag is then placed in the toilet for
the next astronaut. When the cylinder is filled, it is replaced by
a new cylinder.
-The previous model relied on air flow to pull the waste to a
holding tank. None of the waste was separated as it is now. The
new system provides better hygiene conditions. There was no way to
empty the old system. When it was full, it simply could hold no
more waste materials. It had a 14 day capacity.
-The new toilet also provides an odor-free environment. The old
model did not.
-The opening in the lid of the toilet was increased from 4" to 8",
allowing for easier handling of the plastic storage bags.
-The urine collection system was also improved. A newer type of
fan system is being used to force the urine to a holding tank where
it is periodically ejected into space, where it vaporizes.
-The previous system had trouble with corrosion in the fan system.
-The new toilet can be cleaned without removal from the orbiter at
the completion of the mission, reducing the cost of servicing.
-The previous system must be removed and sent to a company in
Houston, Texas for servicing.
I hope this helps.
Jonathan Keohane and most all of the Ask an Astrophysicist Team
-- for Imagine the Universe!
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