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Purchase lunar simulant (lunar soil)
to help support our science and zero-gravity outreach program.
Invite Ben to give a talk at your middle school,
high school, or other function. Email Ben at bwlongmier@gmail.com
with the title 'Zero-G'.
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Video of Ben spinning somewhere South
of Houston over the Gulf of Mexico onboard NASA's KC-135a
Video
of spinning in Zero-G (10MB streaming avi file, right click
to download)
 
'Zero-Gravity' is produced within the KC-135a airplane by flying
along an inverted parabolic arc. During moments of weightlessness,
people can be tossed about the plane with little or no effort. John
Yaniec, the lead test director, holds a student in place with a
light touch. John's feet are strapped to the bottom of the plane
so that he does not float away. The weightlessness lasts for about
25 seconds, just enough time to perform scientific experiments in
reduced gravity or to enjoy floating around the cabin and spinning.
Ben floats to the ceiling of the KC-135 as another student practices
an improved technique for weightless CPR.
The 'Weightless Wonder' (informally/infamously known as the 'Vomit
Comet') climbs at about 45 degrees and dives at about 45 degrees
in order to follow the proper inverted parabola to produce a weightless
environment within the cabin of the airplane. A combination of drugs
(scope-dex) are taken by most people before they fly onboard the
Vomit Comet to help with motion sickness. NASA provides participants
with Scopolomine (an anti-nausea medication) and Pseudoephedrine
(a stimulant to combat drowsiness resulting from the Scopolomine).
The term zero-gravity is a bit of a misnomer because some amount
of gravity exists all around us at all times (even in space and
in between the galaxies). The airplane simulates what it would be
like to exists in a zero-gravity environment. Think of it like sky
diving with an airplane cabin around you. In sky-diving a person
only gets about 3-4 seconds of freefall before terminal is reached.
Terminal velocity is the speed at which something being dropped
(in this case human) will fall at a constant velocity, this happens
when the force of gravity of the object equals the wind resistance
(drag). For a person jumping out of an airplane it is about 120
MPH. The KC-135 effectively reduces the drag by increasing the thrust
of its engines and can let a person freefall for a much longer period
of time (~25 seconds). Because the plane needs to keep flying, it
needs to have a component of its velocity in the horizontal direction
in addition to the vertical direction (hence the inverted parabolic
shape). Weightless can also be produced by shooting something up
into the air and then letting it fall back down to earth, this is
done in some amusement park rides (the
Spaceshot). Weightlessness can also be achieved by some rollercoasters
if they follow the correct path and the KC-135 can be thought of
as one very big roller coaster in the sky. The KC-135 starts out
at 26,000 ft, climbs to 34,000 ft, drops to 26,000 ft and repeats
up to 40-50 times, with each weightless period lasting 25 seconds.
The min and max airspeeds of 325 kts and 510 kts occur at the top
and bottom of the curve respectively.
2004 UW Reduced Gravity Team, (left to right) Stephen Steiner, Emily
Prewett, Tim Swenson, Ben Longmier, Mark Schneider
2005 UW Reduced Gravity Team, (left to right) Tim Swenson, Doug
Lipinski, Mark Schneider, Ben Longmier, Emily Prewett, Mai Lee Chang.
Mark Schneider (left) and Ben Longmier in front of the 2004 glove
box containing our Aerogel
experiment.
Hypobaric chamber testing. All of the student s that fly onboard
the KC-135 undergo high altitude training. This chamber is effectively
a vacuum chamber where they simulate the air pressure at 24,000
ft. In this condition a person has about 3-4 minutes of 'useful
consciousness before they pass out from oxygen deprivation. Notice
the facemasks, they provide pure oxygen until the chamber reaches
the correct internal pressure. In a pure vacuum (i.e. in space)
a person has about 9-12 seconds before they lose consciousness.
This time is much less than the time a person can hold their breath
because oxygen in this environment essentially boils off of the
lung tissue and is lost into the vacuum instead of the oxygen staying
in the lungs and blood stream and being used up at a slow rate when
a person holds their breath. Although a person may lose consciousness
after 9-12 seconds, a highly trained astronaut can survive for 2-4
minutes (brain tissue dies after 3-5 minutes if starved of oxygen)
in a vacuum if properly reintroduced to an air supply after that
time.
Picture of Ben before taking his oxygen mask off and Ben after 4
minutes of breathing normal air (20% oxygen) at a pressure of 5.5
psi, the same pressure experienced at an altitude of 25,000 ft (see
level pressure is 14.7 psi). As with all oxygen deprivation, colors
tend to increase in brightness and a feeling of euphoria is experienced.
Unlike other types of oxygen deprivation, this is completely safe
and the effects disappear after the chamber is vented to atmospheric
pressure.
NASA requires that student experiments pass a Test Readiness Review
before they are allowed to fly onboard the KC-135. Here, Stephen
Steiner explains the details of operation and safety precautions
to a group of NASA scientists.
The Neutral
Buoyancy Laboratory (NBL). This is a large pool that is 60 ft
deep and is used for training astronauts to perform work in space.
A module of the International Space Station can be seen underwater.
Although this does not produce weightlessness, it is really the
closest thing to floating that a person can experience without flying
on the KC-135 or falling. When I went on the KC-135, the closest
thing that it reminded me of was being neutrally
buoyant when I have been SCUBA diving before.
A thin gold film on an astronaut's helmet visor serves as a protective
layer against UV radiation and excess light when working in space.
Other Zero-Gravity Sites
UW CAP Zero-G
Team 2006
UW
RM Zero-G Team 2005
UW Zero-G
Aerogel Team 2004
NASA's student
micorgravity website
Book a Ride with
Zero-G corp. ($3750)
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