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Transcript for NASA Connect - Proportionality - The X-Plane Generation
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[ Music ]
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[Collins] Hi.
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I'm astronaut Eileen Collins.
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You may remember me as
the first woman to pilot
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and to be named a space
shuttle commander.
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You know, when I was a
child, I dreamed about space.
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I knew that I'd have to study
math and science if I wanted
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to become an explorer myself.
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In today's episode of NASA Connect,
you will see how NASA engineers
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and scientists are using a
math and science to build
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and test scale models
of spacecraft.
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You will also get to
make your own model
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of the NASA spacecraft
using your knowledge
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of ratios and proportions.
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So hang on as hosts Dan Hughes
and Jennifer Poli connect you
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to the world of math,
science, and technology
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on this episode of NASA Connect.
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[ Music ]
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[Jennifer] Take it
easy, take it easy.
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Are you all right?
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[Dan] No. This is terrible.
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[Jennifer] What's the matter, Dan?
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And why did you insist that
I meet you here on a bicycle?
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[Dan] Come on, we
haven't time to lose.
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[Jennifer] Wait a minute.
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Dan, Dan! Let me just see
if I've got this straight.
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You've come to Huntsville
Alabama to go to space,
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but decided you will show up days
early to be in a 20 mile bike race?
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[Dan] No, Jennifer.
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It's a 25 mile bike race.
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[Jennifer] I never knew
that you raced bikes.
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[Dan] I didn't either.
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I mean, I never have.
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I'm exhausted.
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What was I thinking?
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I'm sure to lose.
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[Jennifer] Well, can't
you just withdraw?
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If you like, you can go
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to the outdoor sports
conference that I'm attending.
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I'm sure you'll find the
speakers and sports fascinating.
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They'll even discuss bike racing.
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I know. We'll train
again next fall,
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and sign up to race next year.
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[Dan] No. I feel obligated.
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And besides, the entry
fee is nonrefundable.
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[Jennifer] Okay, so
you are committed.
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But why the negative attitude?
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I mean a damn, you
could win this race.
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[Dan] You're right.
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Based on the one-mile test run I
did this morning, I may be destined
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to enter the record books as
the worst bike racer ever.
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[Jennifer] Well, the one-mile
test run was a great idea.
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And you know, I have friends at
NASA Marshal Space Flight Center
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in Huntsville, Alabama.
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They conduct tests on their
vehicles before flying them.
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And who knows, maybe --
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[Dan] Are you saying that I should
get a rocket engine put on my bike?
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[Jennifer] Not exactly, relax.
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Come on. It's downhill
most of the way.
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[Dan] OK. Let me get
some energy, some food,
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my energy is running low as well.
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[Jennifer] All right.
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While you're doing that, why
don't we meet back at the US Space
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and Rocket Center in,
say, about an hour.
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And then we'll go there.
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[Dan] All right.
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[Jennifer] Meanwhile,
let's head over to one
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of NASA's research
partners, the University
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of Alabama at Huntsville.
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Dr. Clark
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[unclear], a professor
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at the university's propulsion
research center is there waiting
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to tell us more information
on energy and motion.
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[Clark] Energy and motion are found
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in common everyday
things we find around us.
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Energy is the capacity for doing
work, and motion is the term we use
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to describe things moving
from one place to another.
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I can illustrate energy and its
transformation using this ball.
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I put work in by raising it up
to this height above my head,
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and then I transformed into energy
of motion as I let go of it.
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Now we'll go over to our
propulsion test facility,
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and meet with engineering
student Melanie Janetka.
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[Melanie] What we do here
is test small-scale versions
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of rocket engines to see how the
real ones will behave in flight.
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That's a whole idea
behind proportionality.
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And doing it this way makes
space transportation safer,
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more affordable, and more reliable.
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By taking his bike on a test run,
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Dan was able to see how his bike
would perform in an actual race.
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Proportionality is
the use of ratios.
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In other words, this engine is
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about 2000 times smaller
than the real thing.
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Dan's test run was 25 times shorter
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than the distance he
will travel in the race.
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Proportionality is
used for everything.
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That includes art,
cooking, and architecture.
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[Clark] When we are designing
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and testing state-of-the-art
multimillion dollar stadiums,
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there are several steps we must
take even before ground can
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be broken.
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One of those steps is
to build the stadium,
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but on a much smaller scale.
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We called this proportionality.
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It's the use of ratios
like 1:100 in scales
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in order to meet challenges.
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It's nothing new.
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It's likely the Egyptians used this
to help build the great Pyramids,
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and the Romans to help
construct the Coliseum.
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Today, proportionality
is used everywhere.
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NASA even uses this to help
construct future spacecraft.
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This is a scale model of
the Raymond James Stadium,
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home of the Tampa Bay Buccaneers.
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Every inch here was 100 feet or
1200 inches of the real thing.
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A lot of this goes
back to math class.
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It's all about proportion
and scaling things.
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We pay close attention to the
relationship between sizes.
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[ Music ]
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[Voices] Unclear.
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How would a test engineer
use computation?
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[Melanie] Force is the capacity to
do work or cause a physical change.
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Now that was the force
of gravity at work.
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The work that we're doing
here deals with propulsion.
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We are developing ways to overcome
the force of Earth's gravity.
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Unclear is the power of
available for us to use.
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We get our energy by fueling
our bodies with healthy foods.
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When we ride our bikes, our human
body is a machine that propels it.
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Rockets carry their own
propellants as an energy source.
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The proponents are
burned in the engine,
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which provides the force
needed to reach Earth orbit.
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Last but not least is
calculating, or computation.
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Simply put, that's working with
numbers to make them work for us.
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We use computation before, during,
and after these rocket tests.
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All of these concepts can be and
are perceived in our everyday lives
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with all sorts of problems.
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[Jennifer] Mike, how do you
get ready for a bike race?
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Hey John. Thanks for meeting us.
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This is my friend
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[Dan]
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[Voice] Hi Dan and Jennifer.
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I'd like to welcome both of you
to the Marshal Space Flight Center
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and to our historic test area.
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Dan, we understand that you're
involved in a bike race.
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And in any race, it's
important to understand
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where you've been before you
figure out where you're going.
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[Jennifer] Some pretty historic
boosters tested right here
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in these test areas.
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The measurements taken here
on the ground were used
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to calculate how the real
thing would operate in flight.
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What they did was some
truly amazing things.
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You know, it wasn't that long ago
that people talked about something
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that was impossible to do, they'd
say, you've got as good a chance
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of doing that as going to the moon.
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[Recording] Tranquility Base here.
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The eagle has landed.
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[Jennifer] I bet NASA doesn't
hear that one too much anymore.
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[Laughter]
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[Dan] You know, this
is really cool.
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But how can it all be related to
my problem with the bike race?
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[Voice] Well, Dan, let's take
a look at what NASA is doing
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in its next generation X plane,
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which in part is being
tested right in this area.
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[Dan] What is an X plane?
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[Voice] Dan, an X plane is an
experimental aircraft built
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specifically for research purposes.
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This is one of the latest explains.
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It's called the X-33.
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This is a 1:50 scale model of the
X-33, which itself is a scale model
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of what we're ultimately
after, which is a single stage
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to orbit reusable launch vehicle
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that Lockheed Martin
refers to as Venture Star.
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[Music]
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[Voice] What is a thermal
protection system or TPS?
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[Voice] Name two examples
of thermal protection.
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[Voice] The X-33 demonstrator
will fly and test
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out the technology used in it to
make going into space more common
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by making it more
affordable and more reliable.
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It takes off vertically
like a rocket
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and lands horizontally
like an airplane.
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The X-33 was designed
with advanced hardware
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that will dramatically increase
launch vehicle reliability.
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The vehicle is designed to reach
altitudes of 60 miles and travel
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at velocities up to 13
times the speed of sound.
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[Dan] What do you
mean by velocities?
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[Voice] Velocity is simply the
speed at which something is moving.
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Try hitting the atmosphere when
you are moving at super velocity,
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and the friction of air molecules
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with the spacecraft become
like sandpaper to a match.
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A thermal protection system,
or TPS, keeps spacecraft
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from burning off when it comes back
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into the atmosphere
on the journey home.
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[Dan] OK. So the X-33 has to
be protected from the heat.
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But can a TPS be used to
protect something from a cold,
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like maybe a special
outfit for me to wear
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so I don't freeze during
this winter bike race?
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[Voice] Yes.
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Some of them are being used
in down to earth applications.
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To keep homes and people protected
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from temperature extremes,
both hot and cold.
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[Voice] Portions of the
X-33 TPS system were tested
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on a high-performance jet at the
NASA Dryden Flight Research Center,
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and also in special
wind tunnel tests
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at the NASA Langley Research Center
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and at the NASA Ames
Research Center.
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[Dan] I just had a small-scale
test with my 1 mile bike ride.
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[Voice] That's right.
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Your 1 mile test run was a
much more manageable size
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to test your bike's technology
than the 25 mile race.
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Because of your testing, you'll be
able to change things on the bike
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and retest more easily.
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[Jennifer] Now although
the tests were conducted
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on two different types of
vehicles, your bike and the X-33,
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they basically serve
the same purpose.
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They use math and science
concepts to overcome challenges.
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OK, Dan, so tell me, what have
you learned from your test run?
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[Dan] That I was exhausted.
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The bike is so heavy it was
really hard to pedal up the hills.
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[Voice] That's because it took
an excessive amount of energy
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to propel the vehicle.
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If you multiply the
energy that it took
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to go 1 mile times the 25
you'll need from the race,
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you can see there's a problem.
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[Voice] I see what you're saying.
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Hey, let's figure it
out mathematically.
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[Voice] OK.
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How can a one-mile bike ride
tell us what a 25 mile bike race
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will require?
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Enter the world-famous ratio.
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The ratio is a way of comparing
the size of two numbers.
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Let's compare Dan's 1 mile test run
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to the 25 mile bike
race he will enter.
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Now, ratios can be
written in numerous ways.
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Like that, or even like that.
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Now all of these ratios are
read the exact same way.
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They are all read 1 to 25.
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Notice ratios can also
be written as a fraction.
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Got it? So, for every
one of whatever it took
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for Dan's test ride,
it will take 25 times
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that in order to complete the race.
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For example, let's
say Dan has to pedal
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on average 1500 revolutions
to go that 1 mile.
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Can you estimate how many
revolutions he can expect to pedal
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in order to complete the race?
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One way to solve this ratio
is to use the fraction ratio
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and set it up like this.
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1 mile to 25 miles equals
1500 revolutions to, what?
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I mean, what number
can you put here
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so that this second
fraction equals 1 to 25?
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It's easy.
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If you multiply 25
times 1500 revolutions,
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that equals, 37,500 revolutions.
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In order for him to complete
the 25 mile bike race,
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he will have to pedal
approximately 37,500 revolutions.
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Better him than me.
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Of course, there are better
ways to solve this ratio.
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What method did you use?
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[ Music ]
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[Voice] How can you improve
the performance of a bicycle?
[00:12:44.649]
[Voice] Explain two
forces that both X plane
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and the bike's performance
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and could you tell us how
they relate to each other?
[00:12:52.409]
[Voice] OK.
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So we've collected the
baseline information
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from Dan's 1 mile test run.
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I think we can all agree that
some improvements need to be made.
[00:13:00.309]
And obviously we can't
change the size of the bike,
[00:13:03.069]
but I mean can't we improve some
[00:13:05.509]
of the bikes technologies
or something?
[00:13:07.059]
[Dan] Yes.
[00:13:07.239]
Make it lighter so it's
easier to pedal or something.
[00:13:09.819]
[Voice] Right.
[00:13:10.329]
You can decrease the force
it will take to pedal
[00:13:12.369]
by decreasing the
weight of the bike.
[00:13:14.199]
One way that you can do it is
to replace the frame with one
[00:13:17.579]
that is made of a new lighter
stronger composite material instead
[00:13:21.879]
of this heavy steel.
[00:13:22.969]
That's something that we
had to do with the X-33.
[00:13:25.679]
[Voice] And we already learned
from our subscale testing
[00:13:28.029]
that both the X-33 in the larger
Venture Star are going to need
[00:13:31.669]
to use composite materials
in order for both
[00:13:33.859]
of them to reach space.
[00:13:35.209]
[Voice] You know, it seems to me
that some of Dan's struggle was
[00:13:38.479]
with poor aerodynamics.
[00:13:40.779]
[Voice] That's another problem
the X-33 and the bike share.
[00:13:44.169]
Moving through the air easily
and with less resistance.
[00:13:47.219]
A lot of this has to
do with the geometry,
[00:13:49.609]
so the shape of the
vehicle is critical.
[00:13:51.679]
The X-33 has a wedge-shaped design.
[00:13:54.629]
I suggest you look for ways to
make the bike more aerodynamic.
[00:13:58.069]
Otherwise, you're just
fighting the force of drag.
[00:14:01.199]
Drag is simply the resistance
of an object caused by the air,
[00:14:04.169]
in this case, through
which it is moving.
[00:14:05.689]
[ Voice ]
[00:14:06.329]
Yes. Since X-33 is
a flying machine,
[00:14:08.599]
we also need to generate lift.
[00:14:10.459]
That is the force
that supports objects
[00:14:12.189]
as they move through the air.
[00:14:13.509]
[Dan] Well, you can't test
that with a test run like mine.
[00:14:16.719]
[Voice] No, but we can
simulate it on the computer.
[00:14:19.389]
And we can run small-scale
models in the wind tunnel.
[00:14:24.109]
[Dan] Oh, OK.
[00:14:24.419]
So we can make the bike less
resistant to air and gravity,
[00:14:29.069]
but what else can we do?
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[ Voice ]
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One thing you can do is you
can make the power source
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more efficient.
[00:14:34.179]
Now on the bike, you
are the engine.
[00:14:36.609]
Are you sure you're using
the gears correctly?
[00:14:38.939]
[Dan] No, I don't even
know how they work.
[00:14:40.579]
I normally just keep it in third.
[00:14:42.269]
[Voice] Well, let me
show you how they work.
[00:14:43.789]
It's really easy and it'll
make you a lot more efficient.
[00:14:46.769]
[Voice] Well, damn, those
gears are there for a reason.
[00:14:49.809]
See, when you are writing or racing
bikes, you want to use your energy
[00:14:53.399]
as efficiently as possible.
[00:14:55.239]
To do this, you need to
use your gears correctly.
[00:14:58.189]
They will help you pedal at the
same rate throughout the race,
[00:15:01.029]
and help preserve your energy.
[00:15:02.939]
For instance, when biking
uphill, use a low gear.
[00:15:06.219]
And when biking downhill or on
a flat road, use a higher gear.
[00:15:11.019]
[Voice] Like the gears
on your bike,
[00:15:12.349]
the X-33 will also
make efficient use
[00:15:14.809]
of the environment it's
traveling through by using
[00:15:17.449]
to revolutionary linear
[00:15:18.979]
[unclear] engines.
[00:15:19.329]
[Voice] That's so cool.
[00:15:21.889]
Hey, let's head to
Cookville, Tennessee.
[00:15:23.959]
There we are going
to meet some students
[00:15:25.269]
who are making their
own models of the X-33.
[00:15:27.839]
[Voices] Welcome to Prescott
Central Middle School
[00:15:32.559]
in Louisville, Tennessee.
[00:15:34.729]
NASA Connect asked us to
show you the student activity
[00:15:38.099]
for this program.
[00:15:39.429]
Under the guidance of our
teachers, Marla Weaver, Alicia Ray,
[00:15:43.479]
and Ronny Amos, we will go
through the steps you will use
[00:15:47.579]
to build the paper skin
[00:15:48.839]
of the X-33 advanced
technology demonstrator.
[00:15:51.879]
In this activity, we will
also measure many dimensions
[00:15:55.649]
of the model, compare these
dimensions to the actual dimensions
[00:15:59.239]
of the X-33, and compute
a scale factor.
[00:16:02.679]
To help you understand about
proportionality and X planes,
[00:16:06.809]
go to the NASA Connect web site.
[00:16:09.299]
Mr. Weaver reviewed what the lines
and labels on the patterning.
[00:16:13.779]
Identify the
[00:16:14.639]
[unclear] lines, cut
lines, and alignment dots.
[00:16:18.349]
He also told us about the
parts of the X-33 vehicle.
[00:16:22.529]
Before we begin, here are
the materials you will need
[00:16:25.319]
for the activity.
[00:16:26.889]
Card stock or heavy paper.
[00:16:29.329]
Pencils, scissors, rulers,
glue, and calculators.
[00:16:33.999]
After you've gotten
your material together,
[00:16:37.409]
we will begin the activity by
constructing the X-33 model.
[00:16:42.059]
Cutting, folding, and
assembling the model will take
[00:16:45.609]
at least one full class.
[00:16:47.389]
Or about 45 minutes.
[00:16:49.399]
Begin cutting out the model
X-33 pattern on sheet one.
[00:16:54.179]
It's important that the cutting and
folding of your X-33 is accurate,
[00:16:58.499]
so that the parts will
fit together and fold
[00:17:00.529]
into an aerodynamic model.
[00:17:03.129]
Please
[00:17:03.429]
[unclear] all the dash
lines, making sure that
[00:17:06.029]
[unclear] lines and
markings are on the inside.
[00:17:09.269]
For results, place a ruler along
the line and hold it down tightly.
[00:17:14.189]
And slide your finger
under the paper and lift it
[00:17:16.799]
up against your ruler.
[00:17:19.369]
Cut the stock for canted
and vertical beams,
[00:17:22.649]
being careful not to cut the
[00:17:24.099]
[unclear] lines.
[00:17:25.519]
Glue tab A at the edge
that says glue A here.
[00:17:30.399]
Repeat for tabs B and C.
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[unclear] and tuck the
[00:17:34.069]
[unclear] into the
front of the X-33,
[00:17:37.619]
and push it in until it stays.
[00:17:40.169]
[Voice] Now you're ready to
cut out the pattern sheet two.
[00:17:44.759]
Unclear along the middle
and fold back the tabs.
[00:17:48.569]
Put the glue on the top part of
the tabs instead of the bottom.
[00:17:52.889]
You can close the rack under
[00:17:55.839]
[unclear] but don't glue it yet.
[00:17:58.279]
Under the back of the X-33.
[00:18:01.339]
Last, cut off the engine,
glue it, and attach it
[00:18:06.249]
to the back of the model.
[00:18:07.769]
Glue your model closed, and now
you are ready for measurements.
[00:18:13.189]
The final measurements
of the full-size X-33.
[00:18:20.679]
Each student should
fill out the data sheet
[00:18:23.239]
by determining the scale
models of the X-33.
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Write the ratio of the
measurements in column D,
[00:18:34.489]
make sure that the
units are the same.
[00:18:37.259]
Using the results, you can now
calculate the scale factor,
[00:18:40.809]
with is the measurement of
a full-size object divided
[00:18:43.769]
by the measurement of the model.
[00:18:45.899]
When all the data is calculated
and entered in column E,
[00:18:48.109]
we are ready to find out
several scale factors
[00:18:50.019]
by adding the scale factors
by adding the scale factors
[00:18:52.969]
in column E and dividing by 3.
[00:18:55.459]
Record your result in the blank.
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Now that we understand the
concept of proportionality,
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we're going to test whether the
model is a true scale model.
[00:19:10.099]
[00:19:10.109]
[Voice] Great job, guys.
[00:19:12.059]
Hey, let's analyze the data by
reviewing the results of activities
[00:19:16.119]
and responding to the
following questions.
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What can you learn
about building a model
[00:19:21.739]
that would be difficult
to learn otherwise?
[00:19:24.719]
How can a model be misleading?
[00:19:28.359]
Pretend the scale factor is 140.
[00:19:32.949]
Now let's apply this scale
factor is a simple problem.
[00:19:36.509]
Decorate the side of your paper
model with the word NASA like this,
[00:19:42.309]
using the scale factor of 140,
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how tall would the
letters be on the X-33?
[00:19:47.729]
Are they bigger than you?
[00:19:50.239]
Let's visit NASA's
[00:19:51.449]
[unclear] Space Center
in Mississippi.
[00:19:54.209]
There, NASA scientists
are testing engines
[00:19:57.469]
to make the X-33 more efficient.
[00:20:00.999]
The difference between the linear
[00:20:02.479]
[unclear] engine and conventional
engines is the shape of the nozzle.
[00:20:07.199]
Conventional engines have a
nozzle that is shaped like a bell.
[00:20:10.499]
And the hot combustion gases
expand along the inner surface
[00:20:13.859]
of this bell.
[00:20:15.249]
However, with the arrows
bike engine, the nozzle is
[00:20:18.309]
that in the shape of
a V called a ramp.
[00:20:21.119]
And the hot combustion gases
expand a long this outer surface.
[00:20:25.279]
This unusual design allows
for more efficient performance
[00:20:30.049]
from the engine, and a more
optimal vehicle design.
[00:20:34.359]
[Voice] Once all the information
is gathered from the various tests,
[00:20:37.729]
it comes time to put
the data to use.
[00:20:46.729]
[00:20:48.809]
[ Music ]
[00:20:49.019]
[Voice] How do engineers use
their models to test their ideas?
[00:20:53.869]
[Voice] What can you
learn from a scale model?
[00:20:57.179]
[Voice] Peter Jennifer and
Dan, welcome to the Skunk Works
[00:20:59.389]
at Palmdale, California.
[00:21:00.979]
This is the location where
we build the X-33 vehicle.
[00:21:04.339]
You can see some of the
parts of the X-33 behind me.
[00:21:07.359]
That's the vertical stabilizer.
[00:21:09.469]
Most parts are mounted in
the back of the vehicle
[00:21:11.709]
to keep it steady during its life.
[00:21:14.379]
You can see here on this scale
model, this model is used
[00:21:19.019]
to evaluate the aerodynamic
performance in a wind tunnel.
[00:21:23.019]
So it is built in exact
proportions to the actual vehicle.
[00:21:27.399]
Now the vehicle is under
construction right here.
[00:21:29.819]
This is the X-33.
[00:21:31.439]
And it is also a proportionate
vehicle.
[00:21:33.609]
It is proportional to a much
larger vehicle called Venture Star.
[00:21:37.999]
Now, we've learned a lot from
proportioning this vehicle.
[00:21:41.339]
We've already changed the
design of Venture Star based
[00:21:43.839]
on what we've learned in the
proportioning exercise on page 73.
[00:21:47.449]
Well, you sure have
seen and heard a lot
[00:21:52.039]
about how proportionality
is used in science.
[00:21:54.429]
Now, bringing it to your computer
desktop is NASA's educational
[00:21:57.979]
technology program manager,
Dr. Shelley Cainwright.
[00:22:00.989]
[Voice] NASA researchers are
constantly testing new technologies
[00:22:06.399]
and designs for X planes.
[00:22:07.869]
Using everything from scale models
to full-sized flying machines
[00:22:10.979]
that carry people, these
researchers evaluate their designs
[00:22:14.249]
by using a basic formula
of building, testing,
[00:22:17.169]
and recording the results.
[00:22:18.889]
I'd like to introduce a class
of eighth-grade students
[00:22:21.299]
from Talladega County Central
High School in Talladega, Alabama.
[00:22:25.129]
They are undertaking
their own investigation
[00:22:27.429]
into proportionality using a
unique model design challenge
[00:22:31.439]
posted at the NASA
Connect web site.
[00:22:33.419]
Let's see what they're doing.
[00:22:35.459]
[Voices] Welcome to Talladega
County Central High School,
[00:22:38.819]
Talladega, Alabama.
[00:22:40.939]
We have been asked by NASA
to ask these questions.
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Can you take a design that
works in one scale and use it
[00:22:48.869]
to design at another scale?
[00:22:50.729]
[Voice] Do you have to change the
design when you change the scale?
[00:22:54.629]
[Unclear] To find out,
we went to Norbert's lab.
[00:22:56.819]
And then went to the National
Langley Research Center kids'
[00:23:00.159]
corner web site.
[00:23:02.199]
We revealed the activity
intro, collected our materials,
[00:23:06.149]
and went to work building with
Egret, a paper airplane model.
[00:23:10.639]
We used the model shop extra
activities to build the Egret
[00:23:14.269]
[unclear].
[00:23:14.549]
We had to come up with ways
to scale up the design plan.
[00:23:19.699]
The term of the
[00:23:20.579]
[unclear] to build
the model airplane.
[00:23:24.989]
[Unclear] and record the result.
[00:23:26.999]
We learned that changing the skill
of a working design is possible.
[00:23:31.229]
[Unclear] revealed some design
problems which were fun to solve.
[00:23:35.189]
We are even planning
to increase the size
[00:23:37.629]
of the model three times
to see what happens.
[00:23:40.549]
We were also able to find
information about aerospace careers
[00:23:44.189]
and to see how NASA uses
models in their research.
[00:23:48.989]
As the students from
Talladega Alabama have learned,
[00:23:51.399]
design and testing scale
models brings its own set
[00:23:54.429]
of unique challenges and questions.
[00:23:56.439]
From Norbert's lab,
viewers can try their hand
[00:23:59.109]
at being a design engineer.
[00:24:01.159]
I encourage our viewers
to visit Norbert's lab
[00:24:03.219]
at the NASA Connect web site.
[00:24:05.029]
And to test their skills
at building the Egret 2X
[00:24:08.029]
and other paper airplane
models that are available
[00:24:10.259]
from a specially created
online aeronautic model shop.
[00:24:15.389]
[Dan] Thank you so
much for your help.
[00:24:17.359]
[Voice] It was our pleasure, Dan.
[00:24:18.489]
I sure hope it helps.
[00:24:19.689]
[Voice] And good luck in the race.
[00:24:20.999]
[Dan] Oh, Thank you guys very much.
[00:24:22.359]
[Jennifer] Thank you guys so much.
[00:24:22.929]
[Dan] Jennifer, get out of the way.
[00:24:23.789]
I've got work to do.
[00:24:24.969]
[Jennifer] Oh my gosh.
[00:24:25.819]
I'd better catch up with
Dan and see what he's
[00:24:27.489]
up to before he gets
into any trouble.
[00:24:29.029]
Dan, Dan, Dan!
[00:24:31.809]
[Jennifer] Wow, Dan, you went out
and bought a bike for this race?
[00:24:36.559]
[Dan] I did not.
[00:24:37.499]
I transformed the old
bike into a lean, mean,
[00:24:41.989]
efficient racing machine.
[00:24:45.119]
[Jennifer] OK down.
[00:24:46.799]
Tell me what you've done
your bike, this incredible.
[00:24:49.659]
[Dan] All right.
[00:24:50.119]
I replaced the old frame
with something lighter.
[00:24:53.239]
But it's still strong.
[00:24:54.919]
I actually figured out
how to work these gears,
[00:24:57.709]
which is the great thing.
[00:24:58.629]
[Jennifer] So you're
not in third gear.
[00:24:59.949]
[Dan] Of course not.
[00:25:00.469]
I'm using them all the time.
[00:25:02.039]
I made the entire bike more
aerodynamic by getting rid
[00:25:04.759]
of these big clunky bags
and using something smaller.
[00:25:07.199]
I'm not carrying around
these shirts.
[00:25:09.519]
[Jennifer] All right.
[00:25:10.619]
So that's what you've
done to the bike.
[00:25:12.249]
What have you done to yourself?
[00:25:14.499]
[Dan] Well, I got an outfit
that you can see today
[00:25:17.629]
to make me more aerodynamic.
[00:25:19.629]
And also this morning, I
ate a very good breakfast
[00:25:22.779]
[unclear] the vehicle.
[00:25:25.169]
I did a 5 mile bike ride.
[00:25:28.429]
It went very well.
[00:25:30.299]
It's proportionately a
fifth of the real race.
[00:25:32.629]
[Jennifer] Gosh, you
sure have learned a lot.
[00:25:34.089]
That's great.
[00:25:36.379]
Show me more about the gears
and show me what else....
[00:25:38.779]
[Dan] Sorry.
[00:25:39.509]
I can't. I've got to
get back to the grind.
[00:25:41.939]
I've got to perfect my bike.
[00:25:43.929]
[Jennifer] All right.
[00:25:44.399]
I'll let you be.
[00:25:45.189]
Well you know what,
good luck in this race.
[00:25:46.979]
Break a leg.
[00:25:47.789]
I mean, win.
[00:25:48.769]
[Dan]
[00:25:48.769]
[Laughter] That's OK.
[00:25:49.899]
[Jennifer] Bye.
[00:25:50.159]
Good luck.
[00:25:51.369]
[Dan] Thanks.
[00:25:51.779]
[ Music ]
[00:25:51.779]
[Voices]
[00:25:52.169]
[Jennifer] Way to go, Dan.
[00:25:57.719]
Well that about finishes up
this episode of NASA Connect.
[00:26:05.829]
But before we go, would like to
thank Marshall Space Flight Center,
[00:26:08.939]
all the NASA researchers,
Lockheed Martin, Peter Frederick,
[00:26:12.749]
Dr. Shelley Cainwright, University
of Alabama at Huntsville,
[00:26:15.949]
and all the middle school
students and teachers
[00:26:17.689]
that helped make this
episode possible.
[00:26:19.449]
Hey, why don't you pick
up a pen or a mouse
[00:26:21.739]
and right as at NASA Connect?
[00:26:23.579]
Dan and I would love to hear your
comments, ideas, and suggestions.
[00:26:27.489]
So here's our address:
NASA Connect.
[00:26:30.479]
NASA Langley Research Center.
[00:26:32.339]
Mail stop 400, Hampton
Virginia, 23681.
[00:26:36.669]
Or pick up your mouse and e-mail
us at [email protected].
[00:26:45.139]
Hey teachers, if you would
like a videotaped copy
[00:26:48.219]
of this NASA Connect show and the
educator's guide lesson plans,
[00:26:52.819]
well then contact CORE,
the NASA central operations
[00:26:56.319]
of resources for educators.
[00:26:58.379]
All this information
and more is located
[00:27:01.299]
on the NASA Connect web site.
[00:27:03.469]