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In this activity, middle
school students view NASA images and movies of Venus, Earth, and Mars to
deduce weather patterns and manipulate computer models to test competing
hypotheses.

By completing this activity,
the learner will
- compare weather patterns
observed on Venus, Earth, and Mars
- manipulate computer models
to investigate the influence of solar distance and atmosphere
- evaluate various solar system
hypotheses using a computer model
National
Science Education Standards National
Mathematics Education Standards
Materials
and Technology
Scientific
Background
Activity
1: Exploration - Analyze the weather and cloud
patterns of Venus, Earth, and Mars and argue which planet has more chaotic
weather patterns.
Activity
2: Collect temperature data using the computer
models from the Solar System Collaboratory (URL).
Activity
3: Change the relative distance, albedo (reflectivity),
and Greenhouse Effectiveness to change Planet X's temperature range.
Activity
4: Evaluate different hypotheses about the
dynamic weather patterns of Venus, Earth and Mars and select the one
which seems most correct.
Activity
5: Answer specific questions relating to
the planet computer models.
Exploration
- Observing the Planets
Consider the weather and cloud
patterns visible on Venus, Earth, and Mars. Which planet has more
chaotic weather patterns? Propose several possible hypotheses.
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 |
 |
Venus |
Earth animatedGIF
|
Mars QuickTimeMovie |
TemperatureRange850
to 900 FRotationalPeriod248 days |
TemperatureRange-70
to 140 FRotationalPeriod24 hours |
TemperatureRange-200
to 40 FRotationalPeriod24 hours |
Concept
Introduction - Computer Models
A class that conducted the assessment
(in the section above) concluded that Venus has more dynamic weather patterns
than Earth, which, in turn, has more dynamic weather patterns than Mars.
Similarly, they noted that Venus has little variation in temperature,
while Earth has a moderate variation in temperature, and Mars has a widely
varying temperature. The class settled on three competing hypotheses.
Your task is to use the computer
model from the Solar System Collaboratory (URL)
to evaluate which hypothesis seems to be the most correct or to propose
your own.
Pat's
Hypothesis |
The
farther away a planet is from the Sun, the colder it is. |
Chris's Hypothesis |
A planet far from the
Sun can be hot if it has a high albedo. |
Aaron's Hypothesis |
A planet far from the
Sun can be hot if it has a high greenhouse effect. |
INSTRUCTIONS
ON HOW TO USE THE SOLAR SYSTEM COLLABORATORY COMPUTER MODELS.
Access
the Solar System Collaboratory Computer Model (image
and real-time access)
[Solar System Collaboratory, University of Colorado,
Copyright 1998]
- The model contains an imaginary
planet, Planet X. Try moving it around (by clicking and dragging)
to see what happens to the temperature gauge on the right side of the
screen.
- Read the temperature gauge
as accurately as you can and CONVERT the Kelvin temperature to Fahrenheit
by entering a number in the KELVIN BOX and clicking in the FAHRENHEIT
BOX. It is useful to remember that 300 K is about room temperature,
70 F.
- Change the characteristics
of Planet X above the temperature converter. You can:
- observe the planet's
temperature as it relates to distance;
- change the planet's albedo
(reflectivity) of the atmosphere in a range of values from 0 to 1;
- change the planet's atmospheric
composition, called the GREENHOUSE EFFECTIVENESS) in the range of
0 to 1000. To learn more about the Greenhouse Effectiveness,
you might want to check out this
on-line resource.
- To get a feel for the numbers,
start by putting Planet X at the same distance as Earth is from the
Sun and start changing the variables of albedo and greenhouse effectiveness
to see what happens to the temperature. Can you make Earth have
a temperature of 75 F?
EVALUATING
THE HYPOTHESES Consider
each of the hypotheses proposed below and test each one using the Solar
System Collaboratory Computer
Model. Analyze the strengths and weaknesses of each proposal
and decide which hypothesis is the best. Or better yet, propose your own
hypothesis and provide data to support your proposal.
Pat's
Hypothesis |
The
farther away a planet is from the Sun, the colder it is. |
Chris's
Hypothesis |
A planet far
from the Sun can be hot if it has a high albedo. |
Aaron's
Hypothesis |
A planet far
from the Sun can be hot if it has a high greenhouse effect. |
Your Hypothesis |
Your Hypothesis Your
Hypothesis
Your Hypothesis
|
[Solar System
Collaboratory Computer Model, University of Colorado, Copyright 1998]
Concept Application
- Asking More Questions of the Computer Models
- How does varying the planet's
distance from the Sun change the temperature? If you double the distance,
does it halve the temperature? If you triple the distance, does the
temperature drop to 3-2 (that is, one ninth) its
original value?
- How good is the model?
Can you replicate the listed temperature on Mercury, Venus, Earth, and
Mars?
- How does changing the albedo
change a planet's temperature? Why does this occur?
- How close do you need to
move Mars in order for it to sustain life? How far away do you need
to put Venus? Can you make these planets sustain life?
Assessment
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