Craters

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Craters

• Final Astronomy Lab

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Lunar Crater Categorization

• In 1978, Chuck Wood and Leif Andersson of the
  Lunar Planetary Lab devised a system of
  categorization of lunar impact craters. They used
  a sampling of craters that were relatively
  unmodified by subsequent impacts, then grouped
  the results into five broad categories. These
  successfully accounted for about 99 of all lunar
  impact craters.

http//www.unm.edu/abqtom/images/Moon/Moon11-19-0
2b.jpg
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The LPC Crater Types

• ALC small, cup-shaped craters with a diameter
  of about 10 km or less, and no central floor. The
  archetype for this category is 'Albategnius C'.

http//www.edwardroach.com/uploads/Albategnius_9-3
-07_504edt_300frames.jpg
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The LPC Crater Types

• BIO similar to an ALC, but with small, flat
  floors. Typical diameter is about 15 km. The
  lunar crater archetype is Biot.

http//www.astrospider.com/images/moon/Biot_LAC98m
ap.jpg
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The LPC Crater Types

• SOS the interior floor is wide and flat, with
  no central peak. The inner walls are not
  terraced. The diameter is normally in the range
  of 15-25 km. The archetype is Sosigenes crater.

http//history.nasa.gov/ap15fj/photos/o/as15-97-13
288.jpg
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The LPC Crater Types

• TRI these complex craters are large enough so
  that their inner walls have slumped to the floor.
  They can range in size from 15-50 km in diameter.
  The archetype crater is Triesnecker.

http//www.damianpeach.com/lunartemp/triesnecker02
.jpg
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The LPC Crater Types

• TYC these are larger than 50 km, with terraced
  inner walls and relatively flat floors. They
  frequently have large central peak formations.
  Tycho crater is the archetype for this class.

http//upload.wikimedia.org/wikipedia/commons/7/7e
/Mooncrater.jpg
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The LPC Crater Types

• Beyond a couple of hundred kilometers diameter,
  the central peak of the TYC class disappear and
  they are classed as basins.

http//www.uwsp.edu/geo/projects/geoweb/participan
ts/dutch/Sudbury/schrodinger.gif
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Question

• How do the variables of velocity, size, and
  meteor angle to surface affect the outcome of
  resultant craters?

http//apod.nasa.gov/apod/image/0507/impact13sec_d
eepimpact_hri.jpg
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Hypothesis

• Develop a hypothesis about the outcome of your
  experiment based on your observations, reading,
  and experience

http//www.photoaxe.com/wp-content/uploads/2007/02
/droplet.jpg
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Your Lab

• You collected data on
• Speed of the impact (depending on height you
  dropped your clay ball)
• Angle of impact (depending on how far back you
  were)
• Size of meteor (depending on whether your clay
  was 1, 2 or 3 pieces)

http//upload.wikimedia.org/wikipedia/en/c/c8/AS11
-42-6285.jpg
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Finish Collecting Data

• Collect your data
• Return all your equipment
• If you have finished your collection, you may
  spend time with the resources

http//crism.jhuapl.edu/education/downloads/GUIDE_
Lesson2.pdf
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Analyze Your Data

• You collected 3 trials of a single variable, then
  collected 3 trials of the next variable, and so
  on.
• Find the mean of each of your variables.
• Add three trials and then divide by 3

1.2 1.3 1.1 3.6 1.2
0.8 1.0 0.9 2.8 0.9 3.0
2.4 3.1 8.5 2.83
1.9 2.3 1.7 5.9 1.96
1.8 1.7 2.1 5.7 1.9 4.2
4.1 4.8 13.1 4.36
3.2 3.8 3.9 10.9 3.63
2.3 2.8 2.8 7.9 2.33 5.2
5.2 8.2 18.6 6.2
4.5 4.3 4.1 12.8 4.26
3.4 3.1 3.1 9.6 3.2 6.0
5.8 6.2 18.0 6.0
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Analyze Your Data

• First, lets look at how our data varies around
  the mean

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Analyze Your Data

• Next, lets start picturing our data using
  averages
• Does this make sense?

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Analyze Your Data

• How about this graph?

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Analyze Your Data

• Or this one.

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Conclusions

• What is your answer about the size, depth and ray
  length as the velocity increases?
• If you have any unusual data, give an education
  guess what happened (most likely, human error)

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For This Lab

• Produce an 8½ x 11 or larger poster of this
  experiment
• Introduction Background on craters (tell me how
  they are formed)
• List your citations

• Methods Describe your experimental design
  (include your hypothesis)
• Results Include both a table and graph of your
  data
• Discussion Tell me what you learned

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Be Creative
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Have Fun
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What Did You Learn
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Include 4 Sections