exoplanets & naked-eye stars

Objects in a System Orbit the Center of MassSo Stars Wobble…

Beta Geminorum (Pollux) Radial Velocity

Beta Geminorum b (HD62509)

• Pollux b has been calculated to have a minimum mass of 2.3 Jupiters

• The planet orbits Pollux at an average distance of 1.64 au.  

• The planet is located in an equivalent position of between Earth and Mars in our solar system.

Winter 2009-2010

GAAC 2/12/2010

The Gamma Leonis system

Companion(in order

from star)Mass

Semimajor axis(AU)

Orbital period

(days)

Eccentricity

b ≥8.78 MJ 1.19 429 0.14

c (unconfirmed) ≥2.14 MJ 2.6 1340 0.13

Gamma 1 Leonis

Even though Gamma Leonis 1b is approximately 1au from its star, it is well outside the system’s habitable zone (hot Jupiter)

Epsilon Tauri

The Epsilon Tauri system[3]

Companion(in order from star)

Mass Semimajor Axis(AU)

Orbital period(days)

Eccentricity

b >7.6 (± 0.2) MJ 1.93 (± 0.03) 594.9 (± 5.3) 0.151 (± 0.023)

Epsilon Tauri b

Epsilon Tauri b orbits within its star’s habitable zone

Winter 2009-2010

GAAC 2/12/2010

11 Umi

Gas giant; eccentric orbit; habitable zone

Gamma Cephei Accretion Disk

The Inner Edge of Habitability Zone is 1.69 AU & the Outer Edge of Habitability Zone is 5.27AU.

Among the hottest of the hot jupiters

Two planets so far, both outside the habitable zone

(4067)

Winter 2009-2010

GAAC 2/12/2010

The 51 Pegasi system

• orbital period = 4.2 days

• observed orbital amplitude = 53 +/- 2.5 m/s

• semi-major axis = 0.05 au

• probable mass = 0.5 Jupiter Masses

Winter 2009-2010

GAAC 2/12/2010

Winter 2009-2010

GAAC 2/12/2010

Winter 2009-2010

GAAC 2/12/2010

Winter 2009-2010

GAAC 2/12/2010

Direct Observation of Exoplanet System HR8799

(Infrared)

Winter 2009-2010

GAAC 2/12/2010

Iota Draconis

7000

6503

6543

69396946

7142

Draco

20h 19h 18h 17h

+65°

+60°

+55°

+50°

NE

3 4 5 6 7

Galaxy Open Cl Planetary

42 Draconis

Exoplanet Search

• Beyond our Solar System

• Total exoplanets 430

• Stars with planets 362

• Gas Giants 270

• Hot Jupiters 89

• Pulsar Planets 4

• Earthlike Planets 0

Exoplanet Discovery, 1989-2010

Winter 2009-2010

GAAC 2/12/2010