Due: November 3, 2021
Since 1995 nearly 4,000 extra-Solar planets have been discovered in more than one-thousand extra-Solar planetary systems. Here, we investigate some things these systems teach us about our Solar System and a few things about how planetary systems in general. Go to http://exoplanets.org/ where you will find a list (Table) of the known planets, the star around which they orbit, their masses in terms of Jupiter's mass (Mjup), their sidereal revolution periods measured in days (Per (d)), the sizes of their orbits (semi-major axis, a) in terms of the Astronomical Unit (AU), and the orbital eccentricity (e).
1. Use the Plots Tool on the website to create Scatter plots of the extra-Solar planetary properties. Produce and then print the following three graphs.
Compared to our Solar System, are your plots similar or different from our Solar System? Do they look as you expected them to look? Explain.
2. If you wanted to decide whether a planet was Jupiter-like or Earth-like in nature, what quantities would you compare to help you to decide whether a planet was Jupiter-like or Earth-like? Decide which quantity is the best guide to determining whether a planet is Jupiter-like or Earth-like. What is your choice? Based on your choice, how many Jupiter-like and Earth-like are in the list? For this question, use the Plots Tool on the website to make and then turn in Histogram plots of the data, for your chosen criteria.
3. What are mini-Neptunes? Estimate the number of super-Earths in the list. _______ Again, state the criteria used to determine which planets are mini-Neptunes. include the histogram you used to arrive at your estimate for the number of mini-Neptunes. What is a Hot Jupiter? Circle the region of Hot Jupiters on your plot for Question 1a. Roughly, how many hot Jupiters are there compared to the number of normal Jupiters?
4. How does the current observational situation concerning the properties of extra-Solar planetary systems affect our basic understanding of the formation of our Solar System? Our theories do not need to be completely revised yet as there are explanations for much of the empirical data. What revisions are suggested by current data on extra-Solar planetary systems?