Lecture 17: Exoplanets II

Question 1

what is spectroscopy for exoplanets and what can it be used for?

Answer 1

technique that analyses the light from a star after it passes through or reflects off an exoplanets atmosphere

can be used to learn about planets size, density etc

Question 2

3 methods of spectroscopy

Answer 2

transit spectroscopy

direct imaging

doppler spectroscopy

Question 3

what are primary and secondary eclipse, and what type of spectra can we take from them?

Answer 3

primary eclipse: a transmission spectrum when the planet transits in front of the host star- absorption

secondary eclipse: an emission spectrum as the planet passes behind the host star

Question 4

explain the existence of hot jupiters and eccentricities

Answer 4

hot jupiters are planets that have masses and radii similar to jupiter, but periods of only 4 days

they likely come form further out and migrate inward

large range of eccentricities likely due to dynamical interactions in multiple planet systems