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Transcript for NASA Connect - The Venus Transit
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[Music]
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[Jennifer] Hi.
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I'm Jennifer Poli, and
welcome to NASA Connect,
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the show that connects you to math,
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science, technology, and NASA.
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Today, we are at NASA
Kennedy Space Center,
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on the east coast of Florida.
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And behind me is the Vehicle
Assembly Building, or VAB.
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This is where NASA
assembles all the components
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of the space shuttle system.
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Kennedy Space Center is also a
site where NASA launches satellites
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that study the Earth
and our solar system.
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In fact, the satellite Voyager 1
which was launched right here back
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in 1977 is very close to
leaving our solar system.
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It's over 13 billion kilometers,
or 8 billion miles, from Earth.
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Can you imagine that?
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13 billion kilometers?
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Whew! It would be hard
to count that high.
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Just look at all the digits
that 13 billion represents.
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I don't know about you,
but it's hard for me
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to imagine just how far a
way 13 billion kilometers is.
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I mean, how large
is the solar system?
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It would probably
make more sense to us
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if we could see a scale
model of the solar system.
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This would give a
better understanding
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of how far away Voyager
1 or the other planets
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in the solar system are from Earth.
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The focus of today's program is
to learn why we use a scale model
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to determine the size
and distance of objects
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in our solar system and beyond.
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In order to learn how to
scale the solar system,
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we must first understand
the concept of scaling.
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During the course of the
program, you will be asked
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to answer several
inquiry based questions.
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After the questions
appear on the screen,
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your teacher will cause the
program to allow you time to answer
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and discuss the questions.
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This is your time to explore
and become critical thinkers.
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Students working in
groups, take a few minutes
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to answer the following questions.
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What does it mean to scale?
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Why is it sometimes necessary
to use scale models or drawings?
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List some math terms associated
with scale models or drawings.
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It's now time to pause the
program and answer the questions.
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A scale model or drawing is
used to represent an object
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that is too large or too small to
be drawn or built at actual size.
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The scale gives the ratio of
the measurements in the model
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or drawing to the measurement
of the actual object.
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Remember guys, a ratio is
a fraction that is used
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to compare the size of
two numbers to each other.
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Let's look at an example.
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One of the most common types
of scale drawings is a map.
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Maps are very useful when planning
a trip, but it is across town
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or across the country.
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Norbert and Za are
planning to drive
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from NASA Kennedy Space
Center to Washington, DC.
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Norbert wants to estimate the
distance he and Za will travel.
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The scale in Norbert's map
reads 1 cm equals 100 km.
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How can he estimate the distance
in kilometers from the space Center
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to Washington, DC,
using the given scale?
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The scale can be written as
the fraction 1 cm over 100 km.
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The first number, 1 cm,
represents the map distance.
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And the second number, 100 km,
represents the actual distance.
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First, using a metric
ruler and the given a map,
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measure the linear distance
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from Kennedy Space
Center to Washington, DC.
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In Norbert, this distance is
approximately 13 1/2 centimeters.
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Now we have all the information
we need to set up our proportion.
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Remember guys, I proportion
is a pair of equal ratios.
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The first ratio is
of the map scale.
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And the second ratio
is the distance
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from Kennedy Space
Center to Washington, DC.
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Let's set these two
ratios equal to each other.
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N represents the distance that
we are trying to calculate.
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This proportion can be
read as 1 cm is to 100 km
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as 13 1/2 centimeters
is to N kilometers.
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In a proportion, the cross products
of the two ratios are equal.
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In other words, the product of
the top value from the first ratio
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and the bottom value from
the second ratio is equal
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to the product of the top
value of the second ratio
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and the bottom value
from the first ratio.
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We can write the cross product
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as 1 cm times N km equals 100
km times 13 1/2 centimeters.
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Using multiplication, Norbert
calculated the actual distance
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between the Kennedy Space
Center at Washington,
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DC to be about 1350 km.
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Students, here is an important
point for you to remember.
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Proportions often include
different units of measurement.
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Units must be the same
across the top and bottom
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or down the left and right sides.
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If the units only match diagonally,
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then the ratios do
not form a proportion.
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So guys are you still
having trouble trying
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to understand scaling?
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OK, let's look at another example.
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This time, using a scale model.
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Right behind me is a
replica of the space shuttle.
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And this right here?
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This is a scale model
of the space shuttle.
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The actual space shuttle
has a length of 37.2 m,
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a height of 17.3 m, and
a width or wing span
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of 23.8 m. Now the shuttle
model is a 1:100 scale
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of the actual space shuttle.
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Now that is 1 m equals 100
m. So using that scale,
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let's set up a proportion
to calculate the length
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of the space shuttle model.
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The first ratio is the model scale.
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And the second ratio is
the length of the model
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to the actual shuttle length.
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N represents the length
of the shuttle model.
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We set these two ratios
equal to each other.
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Now remember, in a
proportion, the cross products
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of the two ratios are equal.
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We write the cross products
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as 1 m times 37.2 m equals
100 m times N meters.
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Dividing 37.2 x 100 gives us
the length of the shuttle model,
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which is 0.3 72 m, or
approximately 14 1/2 inches.
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That wasn't too bad, was it?
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Do you think you can handle
the other two dimensions?
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So now it's your turn to calculate
the height, and the width,
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or wing span, of the shuttle
model, using the given scale.
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Remember, the height of the actual
shuttle is 17.3 m. The width
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or wing span is 23.8 m. And the
scale is 1 m equals 100 m. It's now
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time to pause the program
to calculate the height
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and width of the shuttle model.
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So guys, how did you do?
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Let's check your answers with mine.
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Earlier, we calculated the
length of the shuttle model
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to be 0.372 m. I calculated the
height of the model to be 0.1 73 m,
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or approximately 7 inches.
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And the width or wing
span to be 0.2 38 m,
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or approximately 9 1/2 inches.
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Did you get the same answers?
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If you did, great job.
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And if you didn't,
don't be discouraged.
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Just go back and checked
over your work carefully.
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Make sure you set
up your proportions
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and multiplied correctly.
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You know, scientists and
engineers learned a great deal
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from making mistakes.
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Now that you have a better
understanding of scaling,
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let's turn our attention to
the focus of today's program,
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which is scaling the solar system.
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Dr. unclear, an astronomer
and scientist
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at NASA's Goddard space
flight Center, has the scoop.
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[Stan] Thanks, Jennifer.
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When we talk about the differences
between points of interest,
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we instinctively use the
units that make sense
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to us and our convenient.
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For example, what unit
of measure would you use
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to describe the distance
from Washington,
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DC to Los Angeles, California?
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Would you use miles, inches,
kilometers, or meters?
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What about your height?
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Would you measure it
in inches or feet?
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And how about the width
of your classroom?
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Do you use kilometers,
meters, or feet?
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You can use any unit of measure you
wish, as long as it's convenient
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for everyone to understand.
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When describing distances of
the scale of the solar system,
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even units like miles and
kilometers lead to numbers that are
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in the millions or the billions,
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and that makes it very
hard to understand them.
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For example, the distance
between the Earth and the sun is
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about 149 million kilometers.
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Between the Sun and Pluto,
this is about 5.9 billion km.
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But suppose we wanted to
compare these two numbers.
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It's not easy to see that
Pluto is about 40 times as far
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from the sun as birthdays.
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It would make sense to use
a smaller scale in order
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to get a better idea of the
distances between the planets.
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To come up with that scale,
we have to define a baseline.
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The baseline that
astronomers use is the distance
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between the Earth and the sun.
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This distance is known
as the astronomical unit.
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The astronomical unit or
AU represents the distance
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between the Earth and the sun,
which is about 93 million miles.
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The astronomical unit is the
baseline that astronomers use
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to determine the distances to
the planets in our solar system
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and to the stars beyond.
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So let's have a look at the
scale of the solar system
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where one astronomical unit
equals 93 million miles.
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Based on the astronomical unit,
it's easy to compare the distances
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between all the other
objects in the solar system.
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The accompanying chart shows
the distances to the planets
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from the sun in terms
of astronomical units.
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Let's look at Mars.
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We can quickly see that Mars is
one of a half times further away
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from the sun and Earth is.
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So how far is Mars
from the sun in miles?
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Remember the process and Jennifer
demonstrated earlier in the program
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to solve problems
involving scaling?
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We can solve the Mars distance
problem using a proportion.
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The first ratio is the scale,
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and the second ratio is the
distance of Mars to the sun.
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And Miles represents the
distance from Mars to the sun.
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After setting these two
ratios equal to each other,
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let's find the cross products.
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The equation becomes one times
N equals 93 million times 1.52.
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Multiplying, we get the
distance from Mars to the sun
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to be approximately
141 million miles.
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Using the astronomical
unit instead of a mile
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or the kilometer makes it
easier to compare the distances
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between the planets and the sun.
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For example, it's easier to
remember that Mars is one
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of the half times further away
from the sun than the Earth
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than it is to remember that it's
48 million miles further away
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from the sun than the earth.
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If you recall from
earlier in the program,
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the Voyager spacecraft
is 8 billion miles
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or 13 billion km from the earth.
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It's at the far edge of our
solar system, ready to head
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out into interstellar space.
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Based on what you've learned about
scaling and the astronomical unit,
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can you estimate the distance
of a Voyager 1 from the earth
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in astronomical units?
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Working with a partner,
take a few minutes and see
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if you can solve this problem.
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Voyager 1 is over 8 billion
miles away from Earth.
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Estimate how far in astronomical
units Voyager 1 is from the earth.
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Remember the scale is one
astronomical unit equals 93
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million miles.
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Teachers, you may
now pause the program
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so students can answer the problem.
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OK, so what did you come up with?
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If you said that Voyager was
86 astronomical units away
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from the earth, you're correct.
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Do you have a sense
for how far that is?
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The planet Pluto is 40 astronomical
units away from the earth.
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So that means that Voyager is
twice as far away from the earth
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than the planet Pluto.
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Suppose that Voyager 1 were
stationary, and you were able
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to ride in a car traveling
at 55 mph to get to it.
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The trip would take you
over to 16,000 years,
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just to reach the satellite.
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That would be quite a lengthy
and expensive vacation.
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Jennifer, I think the
students are ready
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for that hands-on activity now.
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Could you send them back to
me when I you're finished?
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I have a real tough
question for them to answer.
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[Jennifer] Thanks, Stan.
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We'll get back to you a
little later in the program.
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But first, students from Brewster
Middle School at Camp Lejeune,
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North Carolina, will preview
this program's hands-on activity.
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[Voices] Hi.
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NASA Connect has asked us
to show you this program's
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hands-on activity.
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In this activity, you will
use graphing, measurement,
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and ratios to construct a
scale model of the solar system
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and relate each planet to the sun.
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And you will explore the skills
needed to represent the size
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of the planets and the
distances to the sun.
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You can download a copy
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of the educator guide containing
directions and a materials list
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from the NASA Connect web site.
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Working in groups, students
will complete the activity
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by using a scale model chart
and the planet templates.
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Each group will be
a signed a planet.
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Cut out your assigned planet
using the planet template.
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The scale for this activity
is one toilet paper sheet
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equals 30,102,900 km.
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Using the scale, students complete
column 4 in the scale model chart.
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Remember the math concepts you
learned earlier in the program?
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This is your chance to put
your math skills to the test.
[00:15:06.768]
Next, you will complete column
5 on the scale model chart.
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The scale needed to
complete this column is 1 AU
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or astronomical unit equals
five toilet paper sheets.
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Groups should check
each other's work
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to make sure all values
are correct.
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After completing the scale model
chart, each group should roll
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out the number of toilet
paper sheets needed
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for it is signed planet.
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Now it's time to head
to the staging area.
[00:15:33.078]
This could be in a gym,
hallway, or even outside.
[00:15:36.938]
Place the sun in a
central position.
[00:15:39.438]
Students, attach your pre-measured
toilet paper strip to the sun.
[00:15:43.168]
And let it extend outward
in various directions.
[00:15:46.358]
Don't forget to tape your assigned
planet on the end of the strip.
[00:15:50.508]
You will need about 23 m or
75 feet in one direction.
[00:15:55.208]
Based on your solar system
model, you'll be asked
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to answer several critical
thinking questions.
[00:16:00.968]
Graphing is a great way to
visually represent data.
[00:16:04.628]
Each group will construct
[00:16:06.198]
and analyzed two graphs using
an appropriate type of grass
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and scale of your choice.
[00:16:11.968]
Be careful with the type
of graphs you choose.
[00:16:14.388]
Don't forget to check out the
Web activity for this program.
[00:16:17.398]
You can download it from
the NASA Connect web site.
[00:16:19.738]
[Music]
[00:16:20.738]
[00:16:23.858]
[Jennifer] Great job,
Brewster Middle School.
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OK. Now that you guys
have a preview
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of this program's hands-on
activity, now it's time
[00:16:30.838]
to pause the program and see
[00:16:32.518]
if you can construct a scale
model of the solar system.
[00:16:36.188]
So, how was the activity?
[00:16:38.858]
Hopefully, it helped reinforce the
math concepts you learned earlier
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in this program.
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Now, let's review.
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In the beginning of the program,
we talked about the importance
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of scaling, especially when
it comes to maps and models.
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You learned that fractions,
decimals, ratios,
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and proportions are all
important math concepts
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when in dealing with scales.
[00:17:02.218]
Stan introduced you to the
astronomical unit, the unit used
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to scale the solar system.
[00:17:08.388]
Later in the program, I have an
interesting challenge for you.
[00:17:11.708]
But before we get to that, Stan
has a few more questions for you.
[00:17:15.298]
Let's head back to stand
now, and learn more
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about scaling the solar system.
[00:17:21.098]
[00:17:23.448]
[Stan] Hey, it's great
to have you back.
[00:17:25.268]
In the last segment, we introduced
scale of the solar system
[00:17:28.148]
and the astronomical unit.
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Believe it or not, astronomers once
knew only what the distances were
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in astronomical units,
not an actual miles.
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Recall the following chart,
that shows the distance
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of the planet to the sun.
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Between 1609 and 1619,
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the astronomer Johannes Kepler
used precise measurements
[00:17:47.438]
of the planets in the sky
to determine their orbits.
[00:17:50.648]
But his geometric model was based
on the scale of the Earth's orbit,
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not in its actual diameter
in a kilometers or miles.
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He determined the ratio of
the distance of each planet
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to the sun relative to
Earth's distance to the sun.
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His baseline unit, the
distance from Earth to the sun,
[00:18:06.038]
was designated as exactly 1
AU, or one astronomical unit.
[00:18:10.708]
The problem is that Kepler could
not accurately determine the
[00:18:13.368]
distance between the
Earth and the sun.
[00:18:15.408]
The best estimates that at that
time ranged from 50 million miles
[00:18:18.648]
to over 200 million miles.
[00:18:20.808]
But by the 1890s, as farmers began
to know that number very precisely.
[00:18:26.148]
How did scientists, without
modern space technology
[00:18:28.978]
and rockets, do this?
[00:18:30.658]
You can't just send a
spacecraft to the sun and back
[00:18:33.348]
to determine the distance.
[00:18:34.378]
Human life, including
Norbert and Za,
[00:18:37.788]
could survive the intense
heat produced by the sun.
[00:18:40.448]
So the question for this segment of
the program is how did we determine
[00:18:44.038]
that the earth is 93 million miles
[00:18:45.878]
or 149 million kilometers
from the sun?
[00:18:49.188]
This would be a good
time to pause the program
[00:18:51.388]
and discuss the question with
your teacher and your peers.
[00:18:54.948]
So, did you come up
with any good ideas?
[00:18:57.138]
If you didn't, don't
worry about it.
[00:18:58.778]
After all, it took
astronomers about 2000 years
[00:19:01.158]
to figure out how to do it.
[00:19:03.258]
The answer is that astronomers
used a geometric technique called
[00:19:08.288]
parallax to determine the distance
between the Earth and the sun.
[00:19:11.298]
Parallax is the apparent change of
position of an object when you look
[00:19:14.628]
at it from two different
stations or points of view.
[00:19:17.588]
It sounds mysterious, but we
use this technique all the time.
[00:19:20.928]
For example, let me show you how
parallax works by using my thumb
[00:19:25.238]
and that rocket in the background.
[00:19:27.188]
First, hold your thumb
out at arm's length.
[00:19:30.268]
Now look at your thumb
with your left eye open
[00:19:32.428]
and your right eye closed.
[00:19:34.168]
What do you notice about
the position of your thumb?
[00:19:36.388]
There seems to be an apparent
change in position of your thumb
[00:19:39.258]
from two points of view.
[00:19:41.118]
Your left eye and your right eye.
[00:19:43.318]
Your brain uses this
information to figure
[00:19:45.558]
out how far away things
are from you.
[00:19:47.768]
Actual parallax calculations
can be quite complicated,
[00:19:51.138]
but here's an example of how
we can determine the distance
[00:19:53.508]
to that rocket using many of
the same geometric principles.
[00:19:56.798]
Suppose we wanted to
approximate the distance
[00:19:58.818]
between where I'm standing right
here and that rocket over there.
[00:20:02.548]
And suppose also that there
was a body of water in between
[00:20:05.368]
that we couldn't get across.
[00:20:07.208]
Would you believe that we could
do that by just using a pencil,
[00:20:10.018]
a piece of paper, a ruler, a
piece of rope, and a protractor?
[00:20:14.398]
The first thing we do is to
lay a rope in a straight line.
[00:20:17.918]
The rope will serve as our
baseline, and is 10 m in length.
[00:20:22.168]
Standing on the left
end of the rope,
[00:20:24.118]
which we will call position
A, hold the protractor
[00:20:27.078]
so that it is parallel
to the baseline.
[00:20:29.688]
Place the pencil on the
inside of the protractor,
[00:20:32.438]
and move it along the curve until
it lines up with the object.
[00:20:35.588]
Being careful not to move your
pencil, have a partner read
[00:20:38.528]
and record the angle measurement.
[00:20:40.788]
You then need to repeat
the same procedure
[00:20:43.058]
on the other side of the rope.
[00:20:44.658]
We will call this position B. We
now have to angle measurements
[00:20:48.918]
and our baseline measurement,
which is 10 m,
[00:20:51.348]
the length of our rope.
[00:20:52.028]
In a sheet of paper a long the
bottom, we draw a line 10 cm long
[00:20:57.028]
to represent our baseline.
[00:20:59.348]
For this exercise, let the
scale be 1 m equals 1 cm.
[00:21:05.558]
Mark one end of the drawn line
as point A, and the other end
[00:21:09.758]
as point B. Using our protractor
at point A, we measure an angle
[00:21:14.908]
that is the same number of degrees
as the angle measured outside
[00:21:18.888]
for point A. Let's mark
and draw the angle.
[00:21:22.908]
At point B, we do the same thing.
[00:21:26.198]
Now measure an angle that is the
same number of degrees as the angle
[00:21:29.448]
that we measured outside
for point B. As you can see,
[00:21:33.528]
the two lines intersect.
[00:21:35.908]
We mark the point of intersection
[00:21:37.448]
as point C. Now we draw a line
perpendicular form point C
[00:21:43.018]
to the baseline.
[00:21:44.718]
Using our metric ruler, we
can measure the distance
[00:21:47.398]
of this perpendicular line.
[00:21:49.448]
Finally, using the scale
of 1 m equals 1 cm,
[00:21:53.328]
we can approximate the
distance the actual object was
[00:21:56.198]
from the baseline.
[00:21:57.748]
For our case, the object
is approximately 20 m away.
[00:22:01.868]
In this example, we used a
geometric technique called
[00:22:04.528]
triangulation, which assumes
that we know the baseline length
[00:22:07.978]
and the two bit angles.
[00:22:09.748]
When astronomers use parallax,
[00:22:11.458]
they measure the baseline
length and the vertex angle.
[00:22:14.278]
It is hard to use the parallax
method in the classroom
[00:22:17.278]
because you can't measure
the vertex angle exactly.
[00:22:20.268]
With proper measuring technology,
[00:22:21.858]
this is not a problem
for astronomers.
[00:22:24.458]
To refine the actual sun/Earth
distance, parallax observations
[00:22:28.268]
of the transit of Venus were
made between 1761 and 1882.
[00:22:33.368]
The transit of Venus occurs
whenever the planet Venus passes
[00:22:36.388]
in front of the sun, as
viewed from the earth.
[00:22:39.298]
But observing the apparent
shift in position of Venus,
[00:22:42.008]
against the background
of the solar disk as seen
[00:22:44.138]
from two different places on
earth, astronomers were able
[00:22:47.198]
to use the parallax shift
to determine the distance
[00:22:50.018]
from the earth to the sun.
[00:22:51.498]
The last Venus transit occurred in
1882, and we are fortunate enough
[00:22:55.008]
to have another transit of Venus
happening on Tuesday, June 8, 2004.
[00:22:59.578]
This is an historic event
because no one alive today was
[00:23:02.608]
around when the last one occurred.
[00:23:04.718]
To learn more about the transit of
Venus, let's visit Dr. Janet Lerman
[00:23:08.388]
at the University of
California's space science lab
[00:23:11.158]
in Berkeley, California.
[00:23:13.318]
[00:23:16.858]
[Dr. Lerman] Venus transit occurs
when Venus crosses the disc
[00:23:19.818]
of the sun as seen by an observer.
[00:23:22.188]
It's like a solar eclipse in
that Venus is located on the line
[00:23:25.478]
between the sun and the earth,
[00:23:27.298]
and therefore blocks
some of the sun's light.
[00:23:29.858]
However, in a Venus transit,
[00:23:32.068]
the sunlight blocked is very
small compared to a solar eclipse.
[00:23:35.718]
And so the observer who is
unaware will never notice it.
[00:23:38.878]
Venus's circular shadow is much,
[00:23:40.938]
much smaller than
our moon's shadow.
[00:23:42.918]
Even though Venus is nearly
the size of the earth,
[00:23:45.438]
it is much farther
away than the moon.
[00:23:47.328]
In clear weather, Venus transits
are visible with the naked eye
[00:23:50.698]
or with a small telescope,
[00:23:52.598]
which is why they became
popular in the 1600s.
[00:23:56.208]
Before the advent of radar,
Venus transits were used mainly
[00:23:59.908]
for the measurement of
the astronomical unit,
[00:24:02.388]
or the Sun/Earth distance,
as you've heard earlier.
[00:24:05.088]
The biggest activities surrounding
the June 2004 Venus transit will be
[00:24:09.208]
the International Network
of Amateur Astronomers.
[00:24:12.848]
These astronomers will
measure the astronomical unit
[00:24:15.478]
with the Venus transit using
the same techniques as used
[00:24:18.148]
by the early observers.
[00:24:19.588]
An innovative aspect of this time,
however, not available in 1882,
[00:24:23.868]
is the widespread
use of the Internet
[00:24:25.648]
to organize international
participation,
[00:24:28.248]
and the ease of access
to the tools needed
[00:24:30.358]
to make the parallax calculations.
[00:24:32.478]
There also will be a few
astronomical researchers
[00:24:35.218]
who will try to exploit
state-of-the-art observing tools
[00:24:38.108]
to see what can be learned
about these transits
[00:24:40.668]
to investigate planets
around other stars.
[00:24:43.368]
Transits are currently being
used to search for such planets.
[00:24:46.898]
Perhaps this Venus transit
will lead to some new technique
[00:24:49.808]
or measurements that will
allow future researchers
[00:24:52.348]
to further study the terrestrial
planets during long-range
[00:24:55.448]
planet finding missions.
[00:24:56.868]
The Venus transit will
also serve to remind us
[00:24:59.558]
of Earth's place in the cosmos.
[00:25:01.638]
The tiny dot crossing the solar
disc is a terrestrial planet
[00:25:04.798]
with an atmosphere, and yet
it is far from an Earth.
[00:25:07.618]
Venus was once called a twin earth,
in part because of its similar size
[00:25:11.788]
and distance from the sun.
[00:25:13.558]
It is now known to be a place
that is extremely hostile to life
[00:25:16.858]
for reasons that are
still under study.
[00:25:18.798]
One can speculate how our
own pale blue dot would look
[00:25:21.778]
to some distant alien astronomer
as it passed across the sun
[00:25:25.098]
in transit, and whether it
has ever been so observed.
[00:25:28.398]
Maybe one day humans will be able
to observe the earth transit.
[00:25:31.618]
To learn more about the planet
Venus, and the Venus transit,
[00:25:35.078]
check out the sun/Earth connection
education forum web site.
[00:25:38.698]
Take it away, Jennifer.
[00:25:40.698]
[00:25:43.058]
[Jennifer] They say you learn
something new every day.
[00:25:44.798]
And I sure did.
[00:25:46.248]
I had never heard
of transits before.
[00:25:48.668]
And how astronomers and
scientists used them
[00:25:51.468]
to determine the astronomical unit.
[00:25:53.498]
Thanks, Janet.
[00:25:54.828]
OK, guys. Remember
earlier in the program
[00:25:57.168]
when I said I had an
interesting challenge for you?
[00:25:59.628]
Well, it's now time for
scaling the solar system.
[00:26:03.468]
Now, the astronomical unit or a
you currently in use is derived
[00:26:07.998]
from the average mean distance
between the Earth and the sun.
[00:26:11.248]
Which is approximately
93 million miles.
[00:26:13.478]
Working in groups, your
task is to make a proposal
[00:26:17.508]
that uses the average mean
distance between the sun
[00:26:21.408]
and another planet in our
solar system as the basis
[00:26:25.018]
for determining the
astronomical unit.
[00:26:27.128]
In other words, is there a
better baseline distance to use,
[00:26:31.208]
rather than the Sun/Earth baseline?
[00:26:33.478]
What about using a Sun/Jupiter
baseline or a Sun/Pluto baseline?
[00:26:39.158]
You choose another planet, you
will have to recalculate the scale
[00:26:43.238]
of the solar system using
your new chosen baseline.
[00:26:46.948]
And then explain why your new
baseline is a better choice
[00:26:50.408]
than the Sun/Earth baseline.
[00:26:51.878]
What are the advantages and
disadvantages to your new scale?
[00:26:55.708]
Detailed instructions
and tips on how
[00:26:58.218]
to make your proposal
can be located
[00:27:01.008]
at the NASA Connect web site.
[00:27:02.578]
From the web site, we encourage
you to submit your proposal.
[00:27:06.238]
Your proposal will
be seen by millions
[00:27:08.188]
of students across the country.
[00:27:09.798]
We look forward to
your some medals.
[00:27:11.838]
Well, guys, that wraps up
another episode of NASA Connect.
[00:27:14.788]
I hope you have a better
understanding of how
[00:27:17.558]
and why astronomers and
scientists use scale models
[00:27:21.508]
of the solar system.
[00:27:22.908]
We'd like to thank everyone who
helped make this program possible.
[00:27:26.208]
Got a comment, question,
or suggestion?
[00:27:28.448]
Well, then e-mail them
to connect@LARC.NASA.gov.
[00:27:32.268]
Or pick up a pen and mail them to
NASA Connect, NASA Langley Center
[00:27:36.838]
for Distance Learning, NASA
Langley Research Center,
[00:27:39.458]
Mail Stop 400, Hampton,
Virginia, 23681.
[00:27:43.338]
So until next time,
stay connected to math,
[00:27:46.298]
science, technology, and NASA.
[00:27:49.038]
Bye from sunny Florida.
[00:27:50.178]
[Music]
[00:27:50.178]