Deep Impact-Meteoric Effects on the Lunar Surface

This topic submitted by Charlotte Bornhorst, Robyn MacConnell, Sara Robinson, Kate Weiland (bornhocs@muohio.edu, macconrs@muohio.edu, indygrl581@msn.com, weilankl@muohio.edu) at 2:49 PM on 12/10/02. Additions were last made on Wednesday, December 10, 2008. Section: Cummins

Natural Systems 1 Fall, 2002 -Western Program-Miami University

Deep Impact: Meteoric Effects on the Lunar Surface

The question that our student generated lab poses is as follows: do the size, mass, velocity, and angle with which meteors strike the moon determine the shape, size, and depth of lunar craters? Using basic mathematical principles, we have made several predictions to answer our question. We predict that the size, mass, and velocity of the meteor affect the size (diameter and depth) of the lunar craters. We also predict that the angles at which the meteors strike the moon determine the shape (elliptical or circular) of the lunar craters. We propose that those meteors with a higher velocity and greater mass will result in deeper craters upon impact with the moon. In order to stay focused, we will be researching five craters: Aristoteles, Copernicus, Tycho, Timocharis, and Theophilus. By studying the impact that meteors have on the moon, we hope to understand which factors affect the way craters are created. We primarily want to discover which, if any, of the factors including size, mass, angle, and velocity of the meteors affect the size shape and complexity of the craters they form. We chose this topic because our group had a common interest in astronomy, and we all agreed that the moon would be a highly visible subject. Instead of viewing the moon as an aesthetically pleasing object that is only useful to werewolves and the hopeless romantics, we hope to realize the science and history of its rocky past.

Crater History:

Craters have been a source of fascination for moon gazers for centuries. When observing these formations, one must take into consideration that there are two ways in which lunar craters are formed. Some were formed by volcanic explosions, which blew the rocks of the moon outward and resulted in lava flows and craters. However, the topic of our experiment will focus exclusively on the second type of craters, which were formed by meteorites striking the surface of the moon.

Compression Stage

When a meteor strikes the moon, it trnsfers its kinetic energy to the surface it hits. The equation KE=1/2 mv*v shows us that the kinetic energy is conserved during impact, which mans that the energy is not lost, only transferred. The results of this energy transfer cause a shock wave through the lunar surface, melting or vaporization of both the impactor and target material, and the energy and momentum move and disrupt the lunar surface material. For a meteoric crater to form, three stages must be fulfilled. The first stage is the compression stage. When the meteor impacts the surface, it punches a small hole, which results in a shock wave through the lunar surface. The pressure that is created by the conversion of energy from simply kinetic energy to a combination of kinetic and heat energy causes material from the impact site to become fluid like. During the compression stage, very little material is actually projected out of the impact site. The compression stage is the shortest of the three stages, and the time of impact can be calculated by taking the impactor's diameter divided by its speed at impact, or D/d.

Excavation Stage
The second stage in the formation of a crater is called the excavation stage. During this stage, the crater grows to a very large size in a very short amount of time. The shock wave that was produced in the first stage rises to the surface of the moon, and transfers its energy with it. When the wave reaches the lunar surface, the material is ejected upwards in a cone shaped form. This material is called ejecta, and it is composed of hot vapor, melt droplets, and fine debris. Also included in this mix is breccia, which is different lunar rocks melded together. The original cone is then dispersed in a hyperbolic pattern and lands around the crater forming the ejecta blanket. The excavation stage lasts longer than the compression stage, and it equals the square root of the diameter of the impactor divided by the acceleration due to the gravity of the target.

Modification Stage
The third stage in this three-part process is the modification stage. In this portion, the loose material that was ejected from the crater will slide down the rim of the crater resulting in the possible formation of terraces and/or a central peak. The modification stage will last for approximately the same amount of time as the excavation stage. Basically, the modification stage is simply the settling of the ejecta from the impact.
There are different types of craters that vary due to shape, size, and complexity. Larger craters generally have a diameter of 20 to 30 km and have flat floors and wavy edges. Craters that are between 30 and 40 km in diameter are either regarded as simple craters or complex craters.

Literature Review:

Scientists believe that the best hypothesis for the origin of the moon is that a mars-sized object collided with the earth. The pieces that flew up and out compacted together creating what we now call the moon. It was long after that that the first impact crater appeared on the surface of the moon. Other scientists have researched lunar craters and have come to a conclusion that the average velocity with which a meteor strikes the moon is 20 km/sec. This high velocity causes the size of the crater to be 10 to 20 times larger than the size of the object that caused it. Due to the fact that scientist believe that the surface of the moon has remained unchanged for the last 4,000 million years, they are able to record data on craters which were formed years ago, but remain the same today.

The earliest scientist to view the lunar surface with the help of a newly invented optic tube was Galileo (1609). This tube allowed him to see the lunar surface in more detail and be able to make descriptive observations for his data charts. He challenged long-held Aristotelian beliefs regarding the perfect nature of celestial spheres, which resulted in extreme friction between him and the Catholic Church. Galileo published five books with rough sketches of lunar craters, which spurred on the development of more accurate moon maps by other scientists. Thanks to Galileo's pursuits, scientists were able to view the moon through a telescope and research its surface more precisely.

In 1829, a German scientist by the name of Franz von Paula Gruithuisen made predictions about the cause of craters on the lunar surface. He was the first to suggest that the craters were formed through meteoric impact. He believed that spherical bodies hit the moon and then sank into the surface under their own weight to cause the depressions we can see from earth. He believed these objects to be circular because the edges were scraped off leaving circular walls.

The American geologist Grove Gilbert created experiments with clay in order to represent the formation of lunar craters. As an experiment, he dropped balls of various sizes and shot bullets from a pistol into a clay and sand target. The resulting indenture was a mini model of the craters one can find on the moon. He computed that the average angle of meteoric impact on the moon would be about 45 degrees. He argued that due to this fact all the moon craters would be elliptical or oval.

Eugene M. Shoemaker, a well-known scientist focusing on the moon, gave reasoning in 1969 for the formation of craters on the moon by impacting meteors. Even today, it remains a controversial issue among some scientists as to whether the craters were formed by meteoric impact or through volcanoes. By comparing craters formed by volcanoes on earth to lunar craters, he gathered much data on the differences of these two types of craters and proved his point that the lunar craters were mainly formed by meteoric impact. His argument included that the size differentiation of the meteoric craters varied greatly, whereas volcanic craters are generally within the same size range. Shoemaker also pointed out that volcanic craters are in a systematic formation, whereas moon craters are scattered randomly.

While on the topic of craters being present on the surface of the Earth, we came across much information about these craters as well. There have been 160 craters found on the earth's surface and more are found every single year. When meteors were thought to have hit the earth thousands of years ago they altered the climate, disturbed evolutionary life, and more or less sterilized the earth's surface. The most recent evidence of the mass extinction as a result of these impacts was the extinction of dinosaurs 65 million years ago. One well-known crater is Meteor Crater located in Arizona. This crater has a diameter of 4,000 feet and is 600 feet deep. The area surrounding the crater is littered with debris ejected out of the crater creating hummocks. Hummocks are simply piles of debris ejected from the impact site into the surrounding area. Meteor Crater was formed by a meteor, but scientists cannot find the meteor that caused this depression. Meteor Crater is named as such due to the fact that it was the first recognized crater formed from a terrestrial object.

Meteor Crater

There are two basic types of terrestrial craters: 1) simple: structures 4 km in diameter with over turned rocks and some breccia in the bowl of the crater. 2)complex: structures and basins greater than or equal to 4 km with an upliftin the center that forms a peak, contain some breccia and melted rocks as a result of the impact.

Another, larger crater on the Earth's surface is known as Hole in the Ground. This crater, located 50 miles south of Bend, Oregon, has a diameter of 5,000 feet. Hole in the Ground 425 feet deep, but at one point, it was much deeper. Over time, the bottom of the crater was filled in by sediments carried in by water. This crater is obviously similar to the surface of the moon, due to the fact that astronauts used it for training between 1965 and 1966. The obvious difference between the two is that Hole in the Ground is intermittently releasing bursts of steam. Since the moon has been a cold planet for the last three billion years, none of the craters on the moon emit steam.

Wolfe Creek crater is a very well preserved crater located in the desert plains of Australia. It has a diameter of .875 km, and it has a depth of 50 meters. In the depression of Wolfe Creek, scientists have found meteoric material to prove that the crater was made by a terrestrial object.

Wolfe Creek Crater

Library Sources:
1) Adams, Peter Joseph. The Moon: the nature of its surface, its geology, origin and history, as inferred from recent researches with telescope, spacecraft, and astrophysical techniques. London: H.M.S.O., 1968. This book is a very useful source because it describes in depth about the surface layers of craters. It has numerous photos and information on various semi-recent published research.
2)Cook, Jeremy. The Hatfield Photographic Lunar Atlas. London: Springer, 1999. It provides detailed maps of the moon.
3)Cooper, Bonnie et al. The Moon: Resources, Future Development and Colonization. Chichester: Praxis Publishing Ltd., 1999. This book provides us with useful information about physical features of the moon. These features range from craters to mountain ranges and basins.
4) Dressler, B.O., R.A.F. Grieve, and V.L. Sharpton. Large Meteorite Impacts and Planetary Evolution. Boulder, Colorado: The Geological Society of America, Inc., 1994.
5)Hoyt, William Graves. Coon Mountains Controversies: Meteor Crater and the Development of Impact Theory. Tucson: The University of Arizona Press, 1987. This source gives information about scientists in the past who have researched and/or made discoveries about the moon.
6) Kaler, James B. Astronomy NY: Harper Collins College Publishers, 1994.
7) Kitt, Michael T. The Moon: An Observing Guide for Backyard Telescopes. Waukesha: Kalmback Books, 1992. Each of our craters is described in this book. It includes the best times to see the craters and special features of each one.
8)Leonardi, Piero. On the Origin of the Lunar Craters. Italy: Universita di Ferrara, 1967. It describes the origin of craters and how they are formed and how different factors impact its formation.
9) Loverington, David. A History of Astronomy Great Britain: Springer-Verlag London, 1995.
10) Maran, Stephen P. Astronomy for Dummies. CA: IDG Books Worldwide, Inc., 1999.

11) Moore, Patrick. The Moon. New York: Rand McNally and Company, 1981. It contains photographs and maps of the moon. It gives us a reference point when we are searching for the craters through the telescope. It also includes information on craters on the visible side of the moon.
12)North, Gerald. Observing the Moon: The Modern Astronomer's Guide. Cambridge: Cambridge University Press, 2000. This book provides background information and maps which are helpful in finding craters. It also gives information along with tips on how and when it is easiest to view each crater through a telescope.
13) Pike, Richard J. Geometric Interpretation of Lunar Craters. Washington: US Government Print Off, 1979. This book is useful because it has detailed plans about the structure and shape of certain craters. There are also many pictures with specific details
14) Shaw, Herbert R. Craters, Cosmos, and Chronicles. Stanford, CA: Stanford University Press, 1994.
15) Spudis, Paul D. The Once and Future Moon. Washington: Smithsonian Institute Press, 1996. It gives background information on craters and detailed descriptions of how craters are made. There is also some information about scientists who have studied craters.
16)Waters, Aaron Clement. Moon Craters and Oregon Volcanoes. Eugene: Oregon State System of Higher Education, 1967. It had a lot of articles concerning the controversy over the origin of moon craters (e.g. either volcanic or meteoric).
17) Wlasuk, Peter T. Observing the Moon. London: Springer Verlag, 2000. This book provides a map key with latitudes and longitudes in order to find the craters we will be studying.

Internet Sources:
1) "Craters." The University of Michigan Astronomy Department. Online. 26 Sept. 2002. http://www.astro.lsa.umich.edu/Course/Labs/craters/cr_intro.html It explains how the flour lab works and gives important equations that should be used to fill in the data charts.

2) "Impact Craters on the Moon."Enchanted Learning. Online. 7 Sept. 2002. http://deepimpact.jpl.nasa.gov/science/cratering.html">http://deepimpact.jpl.nasa.gov/science/cratering.html">http://deepimpact.jpl.nasa.gov/science/cratering.html This is a very good source of pictures and it also explains the different stages of crater formation very well.

4) "Planetary Impact Craters." NASA. Online. 17 Sept. 2002. http://rasc.larc.nasa.gov./rasc_new/rasc_fy01_top/CAPS_Overview.html This is the NASA website that gives information about current NASA goals, missions, and real threats of striking meteors.

5) Marsden, Brian. "Eugene Shoemaker (1928-1997)." NASA. Online. 25 Sept. 2002. http://www.jpl.nasa.gov/s19/news81.html It has a detailed description of the life of Eugene Shoemaker, who is mentioned in several other important literatures.

Materials and Methods

Our experimental design involves: careful observation using the Miami University telescope, several experimentations which require launching projectiles against a flour bed, and in depth research on other scientists and their studies.

We will use the university telescope to view our five craters and use the micrometer to take measurements of them. We will take pictures using the telescope, which will be incorporated into our class presentation and final report.

Our flour lab will be used to represent the formation of craters on the moon. We will place a bed sheet on the concrete outside and spread a five centimeter layer of flour on top of it. The projectiles we will use are: an irregular marble, a spherical marble, one random rock, a sticky-tack ball, a golf ball, a billiard ball, a tennis ball, a softball, and a soccer ball. We are using balls of varying weight, shape, and size so that we can get a well-rounded data chart that will show us how these different factors affect the shape of the resulting craters. The ratio we are planning on using is 1km: 1cm. We derived this ratio from the fact that a crater's diameter is about ten times that of the impactor and its depth is 1/5 of the craters diameter. At first, we will drop the objects from a height of 30cm, 60cm, and 90cm directly perpendicular to the flour base. After recording the data, we will throw the objects from an angle of 30 degrees and 60 degrees and use a stopwatch to record the amount of time it takes for the object to hit the flour. After each throw we will measure the diameter and depth of the resulting crater and make a few quick sketches of its shape. Later on we will compile the data using the software StatView and then compare and contrast our results. At the end of our thorough experiment, we will have extensive data charts, sketches, and graphs.

At the beginning of class, we will give a quick multimedia presentation on the background of moon craters and how they are formed. Thereafter, we will ask the class to perform an easier version of our experiment as part of our interactive class presentation. We will divide the class into four groups and give each group different objects. One group will be assigned the ping-pong and golf ball. The second group gets the tennis and the billiard ball. The third group gets the marble and the irregular marble. The fourth group is assigned the sticky-tack and the irregular rock. We will explain how to do this experiment during our presentation and pass out a data chart as an aid.

The specifics of the experiment are as follows:

Step 1-Each group will evenly spread a layer of flour, one to two inches thick, over a provided tray.

Step 2-Use a meterstick and protractor to measure the height and angle of each of the required categories listed in the table.

Step 3-Perform the experiment by throwing each of the two objects into the flour at the heights and angles specified on the data chart. During the experiment, one member of the group should use a stopwatch to time how long it takes from when the object is thrown to when it hits the flour. This should be recorded with the data.

Step 4-Take the measurements of the crater diameter and crater depth and use these results to fill in the data charts. To fill in the column labeled velocity, your group will need to use the equation v=g*t or final velocity=gravity*time. Please list your results in cm/s.

Flour Lab Data Chart
FLOUR LAB

Object name:
Object thrown: _____g

ANGLE & HEIGHT VELOCITY CRATER DIAMETER CRATER DEPTH
30 degrees @ 30 cm
60 degrees @ 30 cm
90 degrees @ 30 cm
30 degrees @ 60 cm
60 degrees @ 60 cm
90 degrees @ 60 cm
30 degrees @ 90 cm
60 degrees @ 90 cm
90 degrees @ 90 cm

FLOUR LAB

After the students perform the experiments, we will ask each group to give us their data charts. We will not, however, ask the students to calculate any of the data themselves. Due to the time constraint of our seminar class and the time spent on both our presentation and setting up and performing the lab, we do not feel as though there will be enough time for these calculations.

Flour Lab Data Chart

We will also do extensive research on other scientists' observations and research. We will use some of the precise data they have collected over the years and compare their results to the data we collect through our own independent experiments and observations. Through this comparison, we will be able to see how accurate our data results are. If our data does correspond with the results of other scientists, we will be able to be fairly certain that our data statistically sound. Although we did not ask anyone for advice, we understand that a group in an NS2 class is also performing an experiment involving the moon, and we will be able to go to them for advice and insight. We will be able to communicate with this group for data information, and these students will be able to be sure we are using the scientific equipment, such as the telescope and the micrometer, correctly.
The biggest obstacle we will need to overcome to ensure unbiased results is to be sure that the students are doing out lab correctly. In order to do this we have arranged to do our lab ourselves prior to the day the class will be performing the experiment. By knowing what kinds of results should be attained, we will be able to see if the results our peers get are accurate.

Larger Relevance
The larger relevance of our research is to understand and show how meteoric impacts affect land surfaces. We could take our collected data and information and see how it would relate to surfaces on the earth. We would be able to hypothesize what would happen if a meteor would hit the earth and what shape, size, and complexity the crater would be. Right now, the government is working through the problem of what to do if a near earth object were to become a threat to the earth. Our options at this time seem to be to blow it up (what else would we want to do?) That could cause lots of little rocks to hit the earth and that might be worse. Or else we could nudge it. Unfortunately, we don't know how much power to put behind the nudge. We don't want to blow it up. But we have to use enough force to "nudge" it.

Even though we are not going into detail about the dust cloud that would result from such a large impact, we would still be able to understand the basic physics behind the formation of such a large crater. We could take our research data and show how the size of a meteor affects the resulting crater and what that would mean in relation to the size of the earth. In a less abstract take on it, we will learn how much velocity, size, shape, and angle at which an object hits a target actually affects the surface it strikes. In context of the moon, we will be able to figure out how large the meteors were that formed specific craters that we are studying. This data could also help us to hypothesize how large a meteor would have to be to wipe out the whole moon!

Results

We spent many evenings outside using the telescope to measure the craters we selected from the moon. Using the micrometer, we were able to estimate the size of each crater. The way in which we did this was to measure our crater in micrometer units. Then, we used the known diameter of the crater Tycho to set up a ratio. Our ratio was as follows:

Micrometer measurement of Tycho = Micrometer measurement of second crater
Actual measurement of Tycho ........... Calculated measurement of second crater

By our measurements, the diameters of the craters were as follows:

Tycho: micrometer measurement 3.7 known measurement 85 km

Aristotles: micrometer measurement was 3.8 calculated measurement 87.3 km

Timocharus: micrometer measurement was 1.5 calculated measurement 34.5 km

Copernicus: micrometer measurement was 3.9 calculated measurement 89.6 km

Theophilus: micrometer measurement was 4.4 calculated measurement 101.1 km

Actual measurements:

Tycho: 85 km

Aristotles: 87 km

Timocharus: 34 km

Copernicus: 93 km

Theophilus: 100 km

By viewing craters through the telescope, we were hoping to be able to view each crater and determine the size of the impacting object that had made it. However, due to the very slow velocity with which our objects were thrown at the flour, all that we discovered is that it would take an object almost the same size as the crater itself to make a crater of that size. We know that this is not reasonable, so we have decided not to include this data. Using the telescope was a great learning experience both with ratios as well as simply learning how to use the micrometer. We also had a lot of fun looking at the moon in the really, really cold weather.

Having fun with the telescope

By analyzing our data in ANOVA and Statview, we have come to the conclusion that the craters produced by throwing objects are statistically similar regardless of the starting point from which the object is thrown. Therefore, the angle and distance at which the object is thrown has no affect of the diameter of the crater it produces. The crater diameter is a function of the object diameter. The object affects the crater diameter due to the fact that the larger the object diameter, the larger the crater diameter will be.

The crater depth depends on the starting position and the object that was thrown. The farther the distance the object thrown from the distance being struck, the deeper the crater will be. The larger the object diameter is, the deeper the crater it will make. Likewise, the more massive an object striking the surface is, a deeper crater will result.

When we compare our hypothesis to our results, we realize that we were correct in predicting that the object diameter, mass, and velocity affect the diameter and depth of the crater. We were wrong in our prediction when our experiment results showed that the angle at which an object is thrown does not determine the shape of the crater it produces. We have come to conclude that a higher velocity of the object being thrown does not have an affect on the depth of the crater. However, the mass of the object does affect the crater depth. These objects have a direct effect on each other:
Direct and Indirect Effects on Crater Forms

Data charts and brief explanation of their results:

1) P-Value (<.0001) = Reject Null Hypothesis

The depth of the craters vary according to the objects. Because we reject the Null Hypothesis, it is clear that they are statistically different. Therefore, we can conclude that the crater depth depends on the object it was struck by.

2) P-Value (.0200) = Reject Null Hypothesis

According to these statistics, the crater depth is directly related to the starting position that the object was thrown from. We rejected the Null Hypothesis and therefore we can conclude that the crater depth is related to the starting position.

3) P-Value (<.0001) = Reject Null Hypothesis

What this test is telling us is that the crater diameters are statistically different!

4) P-Value (<.0001) = Reject Null Hypothesis

The P-Value and the bar graph both show that the circular craters are formed by higher velocities then the elliptical ones.

5) P-Value (.4179) = Fail to reject Null Hypothesis

The bar plot and the p-value show that the two bars are statistically similar. The shape of the crater (circular or elliptical) has no significant difference on the crater depth.

6)The angle at which the object was thrown does not affect the crater's shape.

7) The object's mass effects the crater depth.

8) The object's diameter effects the crater's diameter.

Possible errors within our experiment are as follows:

Telescope:
1)Possibly measuring the wrong crater due to the moon's flipping upside down and left to right.
2) Inaccurate measurements of the craters

Throwing:
1)For the 90 degree drops, the object may not have began exactly at the measurement specified
2) been at the right angle to begin with, i.e. 30 degrees but we threw from 27
3) When throwing the object would not be launched at the correct point due to inaccurate throwing techniques
4)The object would travel a longer distance than desired because it was thrown and therefore had an arc
5)Distance traveled by object would also be inaccurate because we did not have a pitching machine or other more precise device, and rolling spherical objects down a board did not work because the object would just continue to roll across the top of the floor

Measuring:
1)The flour may not have been deep enough to allow the object to reach its full depth potential
2)People measuring crater depth and diameter could have read the ruler wrong; numbers could have been recorded inaccurately, and/or put into Statview inaccurately.

Results:
1)Incorrect interpretation of results

We have found by researching other scientists that the angle with which the meteor strikes the surface of the moon has no impact on the shape of the crater. Regardless of what angle an object hits, the crater that results will always be round. Our theory to explain this is as follows. We believe that the high velocity with which meteors strike the surface of the moon causes the craters to be round regardless of the angle at which they struck the moon. Craters on earth do not always follow this pattern, but our theory on this is that the atmosphere of earth slows the projectile enough that these objects hitting the earth are more similar to our experiment with flour. The very slow velocities with which our objects hit the bed of flour caused some elliptical craters, and the elliptical craters on earth may have been formed for the same reasons.

This realization raises many more questions about craters, especially those on earth. For example, are earth craters non-circular due to the atmosphere slowing down their journey to the surface of the earth, or is the now elliptical shape due to weathering? More questions would include seeing if different types of projectiles make distinctively different craters of the surface of the moon, or how often new craters are formed. Overall, our project has answered some questions, but many more questions about the moon and craters still remain.

Our research with craters has tied in with the reaserch of many other scientists. Just as Shoemaker and Galeleio have had an interest in craters long before we have, we have researched many of the same things. Science has come so far since those times, and each day more is learned about the world around us and things beyond that. We can only hope that someday, all our questions can be answered.

The Moon Group PowerPoint presentation

Our Craters

Aristoteles

Copernicus

Theophilus

Timocharis

Tycho

Timetable:
The first week of October--the group will be taught how to use the telescope so field
research can begin.
Friday, October 11--Use telescope to view and measure Tycho, Aristoteles, Timocharis,
and Theophilus.
Saturday, October 12--Use telescope to view and measure Tycho, Aristoteles,
Timocharis, and Theophilus because it is one of the few days one can see Theophilus.
Tuesday, October 15-- Use telescope to view and measure Tycho, Aristoteles,
Timocharis, and Copernicus.
Thursday, October 17--Meet at science library to review notes from crater observations and
see if more research is necessary.
Friday, October 25-- Use telescope to view and measure Tycho, Aristoteles, Copernicus,
Timocharis, and Theophilus because it is one of the few days to best view Copernicus.
Saturday, October 26--Kate's birthday, day off!
Sunday, October 27--Group members will perform flour lab.
Tuesday, October 29--Meet to discuss the results of the flour lab and compare and contrast
to moon observations.
Tuesday, November 5 --Meet to plan for class presentation.
Thursday, November 7 --Meet to finalize plans for presentation to class.
Saturday, November 9 --Use telescope to view and measure Tycho, Aristoteles, Timocharis,
and Theophilus.
Wednesday, November 13--Use telescope to view and measure Tycho, Aristoteles,
Timocharis, and Copernicus.
Thursday, November 14--Classroom presentation and interactive flour lab experiment.
Sunday, November 17--Meet to finalize lab report and incorporate data from classroom
involvement in experiment. Write final essay and finish the whole lab!
Friday, November 22--PARTY! The lab is finally over!