Exoplanets Flashcards
What is the transit method for detecting exoplanets, and what type of planets is it most effective for?
The transit method involves measuring the luminosity of a star and detecting dips in brightness as an exoplanet travels in front of it. This method is most effective for large planets that directly block a significant portion of the star.
Describe the astrometry method for detecting exoplanets, and what information can be derived from it?
Astrometry involves noticing small deviations or wobbles in the path of a star caused by an unseen body, allowing measurements of the mass and radius of orbit of a large exoplanet that may not be detected by transit.
What is direct imaging in the context of exoplanet detection, and what conditions allow for its success?
Direct imaging is a special case of transit where the star and exoplanet line up perfectly, creating a stellar eclipse. Alternatively, the luminosity of the star reflects from the planet, allowing direct observation.
Explain the microgravitational lensing method for detecting exoplanets, and how it creates observable effects.
Microgravitational lensing occurs when a massive star distorts light, creating an aura or halo around it due to the reflection of light from an exoplanet.
What is the radial velocity method for detecting exoplanets, and how is it employed?
Radial velocity involves measuring the changing red and blue shifts of a star, allowing the detection of small wobbles caused by the gravitational influence of exoplanets.