Lecture Tutorial: Google

Data collected by NASA and other space organizations are becoming increasingly more available to the public through the web. Now anyone can became a planetary scientist using tools like Google Earth and Google Mars. In this lecture tutorial, you’ll explore the various tools available through Google Mars to understand the various surface properties of Mars.

Introduction: Mars from MOLA The first step is to pull up a webpage with Google Mars, which is located here: http://www.google.com/mars

The first map that appears is an elevation map, created from data taken by the Mars Orbiter Laser Altimeter (MOLA), that surveyed the surface of Mars from 1997-2006. MOLA determined the height of the surface by measuring the time it took a pulse of laser light to leave the spacecraft, reflect off the surface of Mars, and return to the detectors. Zoom out on Mars until you can see the whole planet (a quirk of Google Mars is that the map wraps around, so you will see features repeat when you zoom out too much.) Next, Using the MOLA map, answer the following questions:

Highlands and lowlands 1. One of the most noticeable features of the MOLA map is the difference in elevation between the northern and southern hemispheres of Mars. This is called the “ Dichotomy”. Using the elevation bar on your map, What is a typical elevation for the southern highlands?

2. What is a typical elevation for the northern lowlands?

3. What is the difference in elevation between the lowlands and highlands?

4. Looking at the differences in cratering between the northern and southern hemispheres, what can you say qualitatively about the ages of the surfaces in the two different hemispheres?

1 5. What do you think could have caused the difference between the two hemispheres of Mars?

Mountains and Basins

6. Hellas Basin has some of the lowest elevation on Mars. Use the search function to search for “Hellas Basin.” What is the elevation in the bottom of the basin?

7. Use google to find the wikipedia page about Death Valley. What is the depth of Death Valley in km? How does the depth of Death Valley compare to the depth of Hellas basin?

8. What do you think caused Hellas basin, and why?

9. What are the small round “cheerios” on the MOLA map? Are they indented or mounded? How can you tell?

10. Do a search for “” to find Mars’s highest surface feature. What is the height of Olympus Mons? How high is it above its immediate surroundings?

2 11. What do you think caused Olympus Mons?

12. The height of the Earth’s biggest mountain, from base to top, is Mauna Kea. Mauna Kea is 10 km in height. How does this compare to the height of Olympus Mons?

13. Mauna Kea is a Hawaiian volcano, caused by a hot spot, as we discussed in class. What do you think might explain the difference in height between Mauna Kea and Olympus Mons?

Channels

14. Do a search for . What do you think this is?

15. What is the depth of Valles Marineris? What is the length? (Hint: You will probably need to search the internet for this answer.)

16. What do you think is a similar feature on Earth? (Hint: It’s here in Arizona).

17. What are the depth and length of this analogous feature on Earth? Which feature is larger — the one on Earth, or the one on Mars?

The rovers

You can find the landing sites of the last three Mars rovers by typing their names (Oppor- tunity, Spirit, or Curiosity) in the search bar. Two of the themes for Mars exploration

3 have been “Follow the water” and “Search for signs of life”. Use google Mars to inspect each of the landing sites, and explain why you think each of the rovers were chosen to land there. If the reason is not clear, say that, and then try to make guesses about why scientists may have chosen to land the rover there. (Hint: You read about the landing site of the Opportunity rover, , for homework. What was unique about this site??)

18. Spirit Description of landing site and any notable features:

Why do you think the rover landed here?

19. Opportunity Description of landing site and any notable features:

Why do you think the rover landed here?

20. Curiosity Description of landing site and any notable features:

Why do you think the rover landed here?

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