Extra Solar Planets Lab
- There are two types of planets in the solar system, terrestrial planets (like the Earth) and gas giants (like Jupiter). How do the mass, radius, and densities of these planetary types differ?
- Let’s say you discover a planet that’s 50 times the mass of the Earth.Even without visiting the planet, what might you presume about the planet (what will its general characteristics be)?
- How do the distances from the Sun differ for terrestrial and Jovian planets?
- Go to the Web site for the Extrasolar Planet http://exoplanet.eu/ Look through the page. How many planets have been discovered to date?
Click on the “Catalog” icon. Choose Candidates detected by Radial Velocity from the pull down Planet menu. Look through many of the discoveries. Are these planets similar in mass or are they all very different? (Note that masses are given in Jupiter Masses, thus a 1 value is equal to Jupiter’s mass.)
The masses of the planets detected by radial velocity seem to flucuatte greatly. They are not all similar.
Why do we mainly see only mass values? (Think about the Radial Velocity detection method and what information it gives us about a planet.)
Choose Candidates detected by “Transiting Planets”. Do these planets seem to be any different from the “radial velocity” planets?
Why do we see both mass and radius on many of these? (Talk about the detection method.)
Click on the Diagrams button from the very top nav bar. You will see scatter plots or histograms of the properties of the candidates (for example, the numbers of objects in given ranges of mass).Select the Histogram Plot mode (near top right). Select various properties to plot from the pull down menu and observe the results (e.g. orbital period, planet radius, planet mass, etc.). You don’t need to change any other settings.
Answer the following questions:
1. Are most of the planets found using this method more massive or less massive than Jupiter? Note again that the unit “MJ” means “Jupiter masses”.
2. Do most of these planets have orbital periods that are shorter or longer than a year?
3. Are most of the planets closer to or farther from their stars than the Earth is to the Sun?
4. Now select the Scatter plot mode (top right). Here you can look at the relationship between different planetary and stellar parameters for ALL planets that have been found.Inspect (see question below) the plot for PLOT 1: “Semi-Major Axis” versus “Planetary Mass,”; using a linear scale for both axes (change the range of the x-axis to better see the data in certain areas of the plot, like min= 0, max = 10, and then max = 5, max = 2, and so on).
PLOT 2: “Semi-Major Axis” versus “Orbital Eccentricity,” choose x-axis min= 0, max = 10;
PLOT 3a: “Planetary Mass” versus “Planetary Radius” choose x-axis min= 0, max = 5, notice that our Jupiter would be found at (1,1) on the plot. How are these planets different from our Jupiter?
PLOT 3b: keeping the variables the same, change the x-axis min= 0, max = 1, these are all the planets equal to or smaller than Jupiter. How do these planets compare to the ones in our Solar System?
PLOT 3c: keeping the variables the same, change the x-axis min= 0, max = .1, these are all the planets similar to Earth-size, Earth would be at the point (.003,.09), very near the bottom left corner. How do these planets compare to the terrestrial planets in our Solar System?
5. Do you notice any patterns or clumps? What does this tell us about the planets we’ve found? Describe patterns for each plot listed above, be sure to label your answer to each plot.
6. Research what the “Habitable Zone” is for a star and define it in your own words(provide your reference).
a. Where is the Habitable Zone in our own Solary System?
b. What kind of life would we expect to be in this “Habitable Zone” around other stars?
c. What would it take for life to survive outside of a planet’s Habitable Zone? Explain. (What physical processes might be going on?)
d. Are there places in our own Solar System outside the Habitable Zone where we theorize life might exist? Explain, try to be specific in your locations.
Write a summary that includes a short comparison between the properties of the planets in our Solar System that you studied above to the properties of the extrasolar planets you studied here. What conclusions can you draw about Earth-sized planets, are they rare or numerous?
Make sure to include all references.