1. Exoplanets: Radial Velocity Method
This problem involves a common method for finding extrasolar planets based on the Doppler Effect. Please examine the following stellar radial velocity curve, observed over a period indicated on the top and bottom scales in years and days, respectively.
a. Explain how the "Radial Velocity" (or "Doppler") method for exoplanet discovery works in practice.
b. Name two exoplanet properties that can be learned by applying the radial velocity method.
c. What is the orbital period of this planet?
d. How did you determine the period?
e. Based on the Radial velocity curve, would you say this planet's orbit is mostly circular or elliptical?
f. Explain your reasoning for if the orbit is circular or elliptical.
g. From the graph above, what is the maximum radial velocity observed for the planet?
2. Exoplanets: Transit Method
This problem will explore the Transit method of exoplanet discovery
a. Explain how the "Transit Method" for exoplanet discovery works in practice.
b. What is one thing you can learn about an exoplanet using the Transit Method that you cannot learn from the Radial Velocity method?
c. Explain the difference between the "Secondary Eclipse" Method and the "Transit Method"?
d. What is one thing you learn from the "Secondary Eclipse" Method that you can't learn from the Radial Velocity or Transit Methods?
e. For some stars we can detect both a "transit" and a "secondary eclipse." Which one usually causes the deeper dip in light, and why?