Description
Ref: NASA Space Science Data Center (NSSDC)
http://nssdc.gsfc.nasa.gov/planetary/factsheet/index.html (Links to an external site.)
The NSSDC is a standard database for planetary sciences. One method of investigation common in the sciences is to plot lots and lots of data and look for trends. For the 10 solar system objects listed on the given URL, plot two graphs, then answer the questions.
To plot linear or logarithmic data, you have the choice of (1) changing the scale of the axes, or (2) plotting the logarithm
of the data values; your choice (be sure to label your axes properly).
- Make a scatter plot of mean temperature (y) versus distance from the Sun (x). Use a LINEAR scale. NOTE: for the Moon, do NOT use the Moon-to-Earth distance, use the Moon-to-Sun distance (same as Earth-to-Sun distance). Look at the plot. Answer the questions:
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- Describe the trend: rising, falling, or no trend.
- Do the points fall along a straight line?
- Is it easy to identify which point is which planet using only your eyes? Why not?
- Is it easy to identify outliers using only your eyes? Why not?
- For the same data, mean temperature (y) versus distance from the Sun (x), make a scatter plot with a LOGARITHMIC scale for the x-axis only. Look at the plot. Answer the questions:
- Describe the trend: rising, falling, or no trend.
- On which plot, linear or logarithmic, do the points appear to be on a straighter line?
- On which plot, linear or logarithmic, is it easier to identify each planet? Why?
- On which plot, linear or logarithmic, is it easier to identify the outliers? Why?
- Plotting data on logarithmic axes is one way of linearizing a data set. Describe three advantages of the logarithmic axis plot versus the linear axis plot.
- Discuss cause and effect: why is the trend a falling one? You can rely upon your intuition for this response.
- Discuss cause and effect: which is the outlier, and what causes the anomalously high temperature? For this answer you will have to do some research; write a full citation to your source using Chicago style.
Grading: [10] points for the two scatter plots, [18] points for responses to the questions (correct and complete), [2] points for the Chicago style citation. Total points = [30]. Passing grade = [18].
APPENDIX
Plots are easily made using a spreadsheet.
Log in to your Office365 account. You access this from your student account, or go directly to office365.wsu.edu.
Open OneDrive. From the pull-down menu +New select Excel workbook.
Enter the values in columns. Use column A for x values and column B for y values.
Use click-and-drag to highlight the numbers in the columns.
Select the Insert menu. Select “scatter with only markers”.
A plot will appear. You can manipulate the plot by clicking on its various parts. Click the title to change the title. Click on each axis to change the axis to logarithmic, or to add an axis label.