Are there Planets outside Are there Planets outside the Solar System ?the Solar System ?

First answer : First answer : 1992 Discovery of the first 1992 Discovery of the first Extra-Solar Extra-Solar Planet around the pulsar Planet around the pulsar PSR1257+12 PSR1257+12 (Wolszczan &Frail)(Wolszczan &Frail)

Are there Planets moving around Are there Planets moving around other Sun-like stars ?other Sun-like stars ?

The EXO Planet:The EXO Planet: 51 Peg b51 Peg b

Mass: M sin i = Mass: M sin i = 0.468 m_Jup0.468 m_Jup

semi-major axis: a semi-major axis: a = 0.052 AU= 0.052 AU

period: p = 4.23 period: p = 4.23 daysdays

eccentricity: e = 0eccentricity: e = 0

a of Mercury: 0.387 a of Mercury: 0.387 AUAU

Discovered by: Michel Mayor Didier Queloz

Status of ObservationsStatus of Observations

292 Extra-solar planetary systems292 Extra-solar planetary systems

337 Planets near other solar-type 337 Planets near other solar-type starsstars

33 Mulitple planetary systems33 Mulitple planetary systems

43 Planets in binaries43 Planets in binaries

292 Extra-solar planetary systems292 Extra-solar planetary systems

337 Planets near other solar-type 337 Planets near other solar-type starsstars

33 Mulitple planetary systems33 Mulitple planetary systems

43 Planets in binaries43 Planets in binaries

BinariesBinaries

Single Star and Single Planetary SystemsSingle Star and Single Planetary Systems

Multi-planetary systemsMulti-planetary systems

Interesting QuestionsInteresting Questions

How frequent are other planetary systems How frequent are other planetary systems ??

Are they like our Solar System Are they like our Solar System (no. of planets, masses, radii, albedos, orbital (no. of planets, masses, radii, albedos, orbital

paramenters , …. )paramenters , …. ) What type of environments do they have? What type of environments do they have?

(atmospheres, magnetosphere, rings, … )(atmospheres, magnetosphere, rings, … ) How do they form and evolve ?How do they form and evolve ? How do these features depend on the type How do these features depend on the type

of the central star of the central star (mass, chemical composition, (mass, chemical composition, age, binarity, … )age, binarity, … ) ? ?

55 Cancri55 Cancri

5 Planeten bei 5 Planeten bei 55 Cnc:55 Cnc:

55Cnc d55Cnc d -- the -- the only known only known Jupiter-like Jupiter-like planet in Jupiter-planet in Jupiter-distancedistance

Binary: a_binary= 1000 AU

Extra-solare PlanetenExtra-solare Planeten

ca. 130 Planeten entdecktca. 130 Planeten entdeckt

massereich (~massereich (~MMjupjup) )

enge Umlaufbahnenenge Umlaufbahnen

Radialgeschwindigkeits-Radialgeschwindigkeits- messungen messungen

Mass distributionMass distribution

Only 28% of the detected planets Only 28% of the detected planets have masses < 1 Jupitermasshave masses < 1 Jupitermass

About 33% of the planets are closer About 33% of the planets are closer to the host-star than Mercury to the to the host-star than Mercury to the SunSun

Nearly 60% have eccentricities > 0.2 Nearly 60% have eccentricities > 0.2 And even 40% have eccentricities > And even 40% have eccentricities >

0.30.3

Facts about Extra-Solar Facts about Extra-Solar Planetary Systems:Planetary Systems:

Distribution of the detected Extra-Solar Planets

Mercury Earth Mars Venus Jupit

er

Temperature

Lifetime

315stars

Target Stars Target Stars for for

Darwin/TPFDarwin/TPF

A F

G

K

M

10 pc

Sources of uncertainty in Sources of uncertainty in parameter fits:parameter fits:

the unknown value of the orbital line-of-sight inclination the unknown value of the orbital line-of-sight inclination i i allows us to determine from radial velocities measurements allows us to determine from radial velocities measurements only the lower limit of planetary masses;only the lower limit of planetary masses;

the relative inclination the relative inclination iirr between planetary orbital planes between planetary orbital planes is usually unknown. is usually unknown.

In most of the mulitple-planet systems, the strong In most of the mulitple-planet systems, the strong dynamical interactions between planets makes planetary dynamical interactions between planets makes planetary orbital parameters found – using standard two-body orbital parameters found – using standard two-body keplerian fits – unreliable (cf. Eric Bois)keplerian fits – unreliable (cf. Eric Bois)

All these leave us a substantial available All these leave us a substantial available parameter space to be explored in order to parameter space to be explored in order to exclude the initial conditions which lead to exclude the initial conditions which lead to dynamically unstable configurations dynamically unstable configurations

Major catastrophe in less than 100000 years

0 20000 40000 60000TIME (yr)

0.00

4.00

8.00

SEMI-MAJ

OR A

XIS

(S. Ferraz-Mello, 2004)

Long-term numerical integration:

Stability-Criterion: No close encounters within the Hill‘ sphere

(i)Escape time(ii) Study of the eccentricity: maximum eccentricity

Chaos Indicators:

Fast Lyapunov

Indicator (FLI) C. Froeschle, R.Gonczi, E. Lega (1996)

MEGNO

RLI

Helicity Angle

LCE

Numerical Methods

BinariesBinaries

Single Star and Single Planetary SystemsSingle Star and Single Planetary Systems

Multi-planetary systemsMulti-planetary systems

OGLE 06-109LOGLE 06-109LPlanet b:Planet b: (0.71 +/-0.08 M (0.71 +/-0.08 MJJ)) a=2.3 +/-0.2 AUa=2.3 +/-0.2 AU e= ?e= ?

P = 1825 (+/- 365) dP = 1825 (+/- 365) d

Planet c:Planet c: (0.27 +/- 0.03 M (0.27 +/- 0.03 MJJ))

a = 4.6 (+/-0.5) AUa = 4.6 (+/-0.5) AU e = 0.11e = 0.11 i = 59 degi = 59 deg P = 5100 (+/-730) dP = 5100 (+/-730) d

www.univie.ac.at/adg/exostab/www.univie.ac.at/adg/exostab/

ExoStab appropriate for single-star single-planet system

- Stability of an additional planet- Stability of the habitable zone (HZ)- Stability of an additional planet with repect to the HZ

Stability of an additional planet

known parameters of system:

mass of star [M_sun]: 0.5

mass of giant planet [M_jup]: 0.21

semi-major axis of giant planet [AU]: 4.6

eccentricity of giant planet: 0.11

+/- error of eccentricity: 0.05

 newly discovered planet:

Probable range of semi-major axis for the new planet:

semi-major axis of planet [AU]: 2.3

+/- error of semi-major axis: 0.2

Results of theExocatalogue

(Sandor et al., 2007)

The The EXOCATALOGUE:EXOCATALOGUE: http://www.univie.ac.at/adg/http://www.univie.ac.at/adg/

Details:Details:

SándorSándor, Zs., , Zs., SüliSüli, A., , A., ÉrdiÉrdi, B., , B., Pilat-LohingerPilat-Lohinger, E. and, E. and DvorakDvorak, R.: , R.: "A Stability Catalogue of the Habitable "A Stability Catalogue of the Habitable

zoneszones in Extrasolar Planetary Systems"in Extrasolar Planetary Systems", Monthly Notices of , Monthly Notices of

thethe Royal Astronomical Society (MNRAS), 2006 Royal Astronomical Society (MNRAS), 2006

Habitable Zone

Zone around a star where liquid water Zone around a star where liquid water can exist on the surface of a terrestial-can exist on the surface of a terrestial-like planetlike planet

This zone depends on:This zone depends on: the spectraltype , the mass , the age, …. of the the spectraltype , the mass , the age, …. of the

starstar the orbit of the planetthe orbit of the planet the mass, the composition, the atmosphere , the mass, the composition, the atmosphere ,

……of the planet……of the planet the parameters of other planets in this system the parameters of other planets in this system

(mass, orbit, …)(mass, orbit, …)

based on the definition given by Kasting et al. (1993).

Size of the habitable zone of a planetary system

Types of Habitable Zones:Types of Habitable Zones:

(1) Hot-Jupiter type (2) Solar system type(3)+(4) giant planet type: habitable moon or trojan planet

Stability mapsStability maps

Inner region (Solar system type)

Outer region (Hot-Jupiter-type)

ComputationsComputationsdistance star-planet: 1 AUvariation of - a_tp:[0.1,0.9] [1.1,4] AU - e_gp: 0 – 0.5 - M_gp: 0 and 180 deg - M_tp: [0, 315] deg

Dynamical model: restricted 3 body problem

Methods:(i) Chaos Indicator: - FLI (Fast Lyapunov) - RLI (Relative Lyapunov)(ii) Long-term computations - e-max

ANIMATIONANIMATION

How to use the catalogueHow to use the catalogue

HD114729: m_p=0.82 [Mjup](0.93 [Msun]) a_p= 2.08 AU e_p=0.31

=0.001

HZ: 0.7 – 1.3 AU

= 0.005

HD10697: m_p= 6.12 [Mjup](1.15 Msun) a_p = 2.13 AU e_p = 0.11

HZ: 0.85 – 1.65 AU