Exoplanets. II

Sensitivity to Exoplanets

Extrasolar Planet

Detectability

What Have We Found? 1822 planets in 1132 systems as of 9/8/14

(http://exoplanet.eu/ ) 1516 planets + 3359 candidates

(http://exoplanets.org)

•  Detected by radial velocity or astrometry: •  Transiting planets: •  Detected by microlensing: •  Detected by imaging: •  Detected by timing:

First Extrasolar Planet: 51 Pegasi b

Radial velocity/ Doppler Shift

Doppler Wobble: Gliese 876

The three planets of Gl 876: masses = 2.5 MJ, 0.8 MJ, and 7.5 M⊕

Gliese 876

M4V star 3 planets, including the least massive known (0.75 M⊕)

Direct Imaging Example: HR 8799

Transit Example - Ground

Transit Example - Kepler

Microlensing Example

Extrasolar Planets Orbits

Orbital Eccentricity

Extrasolar Planets Orbits

Extrasolar Planets Orbits

Extrasolar Planets Masses

Planetary Mass Distribution

Extrasolar Planets

Planets are preferentially found around metal-rich stars - mostly younger than the Sun.

Metallicities updated

Extrasolar Planetary Systems

55 Cancri (G5V): 5 planets • 1 MU 0.4 AU • 1 MJ 0.15 AU • 1 Ms 0.25 AU • 0.5 MJ 0.8 AU • 4 MJ 5 AU

Earth-like Exoplanets?

N Update

N = N* fs fp • N* = 4 x 1011 • fs = 0.2 • fp ~ 1

N = 8 x 1010