Not all objects in space orbit a planet or a sun. Some objects move about in our universe in a random manner waiting to collide with some other object. The following activity is based on large objects falling from the sky and hitting the earth. 'Natural' space debris that enters our atmosphere immediately begins to burn up due to the friction that the atmosphere causes. Most debris is small enough that it burns up before hitting anyone or anything on earth . But there are objects that are so large that they do not totally burn up and hit the earth. Some cause minimal damage like a hole in the roof, some cause larger damage like a huge hole in the ground called a crater. Some, very few, can cause catastrophic damage like the extinction of the dinosaurs or the end of the earth as we know it. Recently these large 'Asteroids' have been in the news and even some Hollywood movies have dealt with this very subject.

A. Click here to read an article about an Asteroid that may come close to the earth in the year 2014. Click here to read another article that discusses Asteroid impacts and also research on the web to create a  report  that discusses the following points. Maybe make each point a subheading.  To conclude your report include the map that you create in this activity (Part B) and then a final few sentences that discusses any patterns that you might see on the map. Does any part of the world get hit more often and if so, theorize why. Hint: Erosion!

• the size of these objects (how big do they have to be to do any major damage).
• the damage that they can cause.
• how we on earth are monitoring these objects.
• some of the theories of mass extinction that has been attributed to these collisions - think dinosaurs.
• how we might prevent some of the objects (the really big ones) from hitting us.
• discuss how close is close to an Astronomer and mention the latest Asteroids that have missed us. EG.  2001 YB5 or 2002 NY40 and just recently 2003 QQ47.
• why does "where" an asteroid hits make a big difference on the life on earth.
• how many of these objects hit us each year (no matter of size).
• why is it difficult to determine an asteroids size, distance and composition.
• what is the Torino scale.
• What are some of the affects to the major spheres of the earth (atmosphere, hydrosphere, lithosphere, biosphere) - Think!

http://janus.astro.umd.edu/astro/impact.html
http://www1.tpgi.com.au/users/tps-seti/spacegd7.html
http://impact.arc.nasa.gov/
http://www.nmnh.si.edu/paleo/blast/
http://www.space.com/scienceastronomy/solarsystem/asteroid_software_000110.html
http://neo.jpl.nasa.gov

Wow, check this out!

If you know the numerical designation of the asteroid (For example 2002 NY40 - this is the one that could be seen in the night sky this past Aug. 16th or the latest 2003 QQ47). Click here and find the asteroid to get a neat map of the earth and the asteroid and you can manipulate the map to see how close the asteroid got.

B. I have created a .dbf table containing the following information about objects that have hit the earth::

• the place of impact on the earth
• the size of the crater created (Diameter in KM)
• the Latitude and Longitude of the crater

1. Before you start ArcView, I need you to copy and paste a file to your workspace. Navigate to the following directory )
O:\Student Apps\Geo_Data\world.... Locate a file named meteorlist.dbf. Highlight it and under Edit in the main menu select Copy. Then navigate to your workspace and under Edit select Paste.

2. Start up ArcView and begin with a New View. If you get the Welcome to ArcView window, just follow the steps and navigate to 0:\Student Apps\Geo_Data\world\ and select country.shp as your Theme. If you have opened country.shp you can now go directly to Step 4. Otherwise click cancel, in the welcome screen, and you will go directly to the Project Window. If the welcome screen did not appear at all, you will be automatically placed in the Project Window. Now click on Views and then New.  Proceed to step 3 to add a Theme to this new View.

3.Add a Theme (Click on View in the main menu and select Add Theme) that contains a world map showing all the country's boundaries. For example, a country map (country.shp) is found at 0:\Student Apps\Geo_Data\world\country.shp.

4. You may have to go to the Legend Editor (Click on Theme in the main menu and select Edit Legend) and remove the extensive legend that lists all the country's names. Here's how you do it...In the Legend Type window select Single Symbol and then double click on the coloured square that appears and you'll get a Fill Palette screen. Select the icon that looks like a paint brush and select the colour white. Click on Apply and then close all the windows. All you want is a black and white world map without all the country's names.

5. Now navigate to the Project Window (Click on Window in the main menu and then click on the project called Untitled, this will get you to the Project Window, if you have already saved your project, click on the name you gave to project to get to the Project Window) and Add the table that you saved earlier 'meteorlist.dbf'.

6. Now go back to your View and under View in the main menu select Add Event Theme. Make sure that the 'X' field is set to Longitude and the 'Y' field is set to Latitude and that the table meteorlist.dbf appears in the Table window.

7. Click OK and the table will be added as a Theme to your View. You will see it appear in the Table of Contents window, just above the country theme, as a coloured dot. Click on the empty square next to it,  to turn it on.

8. It is a good time to save your project to your workspace. Go to File in the main menu and click on Save As...Navigate to your workspace and give the project a reasonable name. From now on click on the icon that represents a disk to save.

9.You are to create a thematic map classifying the impacts into at least four categories - something like 1. small impacts, 2. large impacts 3. super impacts and 4. planet killers. Make sure this new Theme is active (In other words, simply click somewhere near or on the name to make it active). Go to the Legend Editor and begin customizing your map into a reasonable thematic map based on the size of the impact craters. In the Legend Editor begin by changing the Legend Type to Graduated Symbol and then changing the Classification Field to Size_(km). Click on Classify and change the number of classes to 4 or leave at 5, it is up to you. Finally change the Labels to word descriptions rather than numbers. You can also change the colours of the symbols by click in the Color Ramp window. Once finished click on Apply and close the Legend Editor window.

10. Now is a good time to change the names of the View and the Themes involved. In the main menu click on View and then select Properties and change the name to something more reasonable. You really should just change the name of the event theme you added. Make sure the meteorlist theme is active and click on Theme in the main menu and then Properties to change its name.  You do not want the country theme to appear in the legend because it isn't necessary. Make the country theme active and click on Theme again and select Hide/Show Legend so that it does not appear in your legend of the final map.

11. Time to go to Layout (Click on View in the main menu and then select Landscape to get you to a pre-made, but not complete Layout). You will have to do some editing here before printing the map out. Change things, delete things, move things around and add things, you figure this one out. Be sure to stay within the blue border. Check the PowerPoint show that lists the common errors made when handing in maps made with ArcView. Click here to view that show. Remember to include a legend, a reasonable title, two borders and your name (in the bottom right-hand corner). You do not need a scale. Make sure you make the map pleasing to look at and remember your balance. Note: while you are in the layout click on Layout in the main menu and then Properties click off the Snap to Grid, this makes maneuvering much easier.

12. Once you are finished, save one last time.

13. You are not going to actually print this map out. In Layout click on File in the main menu and then select Export. In the List of File Types scroll down and find JPEG and select it. Give the file a name and navigate to your workspace and save the file. What you have done is saved this map as a graphic image, it can now be inserted into Word or PowerPoint as an image.

14. In a paragraph or two write about the pattern of the impacts that you notice, if there are any. Does any part of the world get hit more often and if so, theorize why. Hint: Erosion!

15. This entire assignment is to be done in Word. Both parts A and B.

16. Once you have completed the assignment email it to me as an attachment. In your Subject box place your name so that I know who it is from.