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Star and Planet Formation Sommer term 2007 Henrik Beuther & Sebastian Wolf 16.4 Introduction (H.B. & S.W.) 23.4 Physical processes, heating and cooling.

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Presentation on theme: "Star and Planet Formation Sommer term 2007 Henrik Beuther & Sebastian Wolf 16.4 Introduction (H.B. & S.W.) 23.4 Physical processes, heating and cooling."— Presentation transcript:

1 Star and Planet Formation Sommer term 2007 Henrik Beuther & Sebastian Wolf 16.4 Introduction (H.B. & S.W.) 23.4 Physical processes, heating and cooling … (H.B.) 30.4 Gravitational collapse & early protostellar evolution I (H.B.) 07.5 Gravitational collapse & early protostellar evolution II (H.B.) 14.5 Outflows and jets (H.B.) 21.5 Pre-main sequence evolution, stellar birthline (S.W.) 28.5 Pfingsten (no lecture) 04.6 Clusters, the initial mass function (IMF), massive star formation (H.B.) 11.6 Protoplanetary disks: Observations + Models I (S.W.) 18.6 Gas in disks, molecules, chemistry, keplerian motions (H.B.) 25.6 Protoplanetary disks: Observations + Models II (S.W.) 02.7 Accretion, transport processes, local structure and stability (S.W.) 09.7 Planet formation scenarios (S.W.) 16.7 Extrasolar planets: Searching for other worlds (S.W.) 23.7 Summary and open questions (H.B. & S.W.) More Information and the current lecture files: http://www.mpia.de/homes/beuther/lecture_ss07.htmlhttp://www.mpia.de/homes/beuther/lecture_ss07.html and http://www.mpia.de/homes/swolf/vorlesung/sommer2007.htmlhttp://www.mpia.de/homes/swolf/vorlesung/sommer2007.html Emails: beuther@mpia.de, swolf@mpia.de

2 M51: The Whirlpool Galaxy

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4 Andromeda CO(2-1) Optical

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6 Mid-Infared view of part of Galactic plane

7 Giant Molecular Clouds Sizes: 20 to 100pc; Masses: 10 4 to 10 6 M sun ; Temperatures: 10 to 15K Superesonic velocity dispersion ~2-3 km/s mainly due to turbulence Magnetic field strengths of the order 10  G Average local densities ~10 4 cm -3 ; Volume-averaged densities ~10 2 cm -3 --> highly clumped material

8 Sites of Star Formation 1.2 mm Dust Continuum C 18 O N 2 H + Optical Near-Infrared Masses: Between fractions and a few 100 solar masses Densities: Of the order 10 6 cm -3

9 Properties of Molecular Clouds Type n Size T Mass [cm -3 ] [pc] [K] [M sun ] Giant Molecular Cloud 10 2 50 15 10 5 Dark Cloud Complex 5x10 2 10 10 10 4 Individual Dark Cloud 10 3 2 10 30 Dense low-mass cores 10 4 0.1 10 10 Dense high-mass cores >10 5 0.1-1 10-30 100-1000

10 Orion

11 The Star-Forming Region W43 Optical Near-Infrared 1.2mm dust cont.

12 Planck's Black Body

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14 Wien's Law max = 2.9/T [mm] Examples: The Sun T  6000 K  max = 480 nm (optical) Humans T  310 K  max = 9.4  m (MIR) Molecular Clouds T  20 K  max = 145  m (FIR/submm) Cosmic Background T  2.7 K  max = 1.1 mm (mm)

15 Properties of Main Sequence Stars Mass Sp. Type Lum T eff t MS [M sun ] [log(L sun )] [log(K)] [yr] 60 O5 5.90 4.65 3.4x10 6 40 O6 5.62 4.61 4.3x10 6 20 O9 4.99 4.52 8.1x10 6 10 B2 3.76 4.34 2.6x10 7 4 B8 2.26 4.08 1.6x10 8 2 A5 1.15 3.91 1.1x10 9 1 G2 0.04 3.77 1.0x10 10 0.8 K0 -0.55 3.66 2.5x10 10 0.2 M5 -2.05 3.52 >10 11 } greater than age of universe t MS ~ 5x10 -4 Mc 2 /L = 1x10 10 (M[M sun ])/(L[L sun ]) yr

16 Sun The easiest to see in night sky and distant galaxies

17 Star Formation Paradigm

18 Jupiter Saturn Uranus Neptun Mars Venus Mercury Earth Gas giants Terrestrial planets Sizes not to scale

19 since 1995: > 200 Extrasolar Planets discovered “Hot Jupiters” High masses Highly elliptical orbits L.R.Cook

20 Overview planet formation (S.W.) 1.Introduction: Stars – Disks – Planets 2.Protoplanetary Disks: Observations 3.Disk models 1.Accretion, Transport Processes 2.Local Structure and Stability 4.Planet Formation Scenarios 5.Extrasolar Planets

21 The solar system: some striking facts Planetary orbits are coplanar Planets orbit the sun in the same direction Distribution of Mass and Angular Momentum: Sun Mass: 99.86% but Angular Momentum <2% Age estimation: Sun and Planets have been formed at the same time Extrasolar Planets: large masses, high excentricities, low orbits

22 Immanuel Kant “Allgemeine Naturgeschichte und Theorie des Himmels” (1755) Solar System is evolving Planets are formed from rotating gas disks

23 Star Formation – Planet Formation Protostellar / Young circumstellar / Protoplanetary Disk: - Gas / Dust disks around protostars - typical diameter: a few 100 AU Planet Formation: “Byproduct” of Star formation: Collapse of a rotating molecular cloud core (angular momentum <> 0) => Formation of a rotating distribution of the infalling material around the central object (Protostar / Pre-main-sequence Star) Circumstellar Disks - “Reservoir” for mass and angular momentum - Environment + Material for Planet Formation - Evolve in time (structure + composition)

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25 McCaughrean et al. 1996

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27 Young Circumstellar Disks [ => Planet Formation ] => Debris Disks HK Tau IRAS 04302+2247 BD+31643 betaPic

28 Star and Planet Formation Sommer term 2007 Henrik Beuther & Sebastian Wolf 16.4 Introduction (H.B. & S.W.) 23.4 Physical processes, heating and cooling … (H.B.) 30.4 Gravitational collapse & early protostellar evolution I (H.B.) 07.5 Gravitational collapse & early protostellar evolution II (H.B.) 14.5 Outflows and jets (H.B.) 21.5 Pre-main sequence evolution, stellar birthline (S.W.) 28.5 Pfingsten (no lecture) 04.6 Clusters, the initial mass function (IMF), massive star formation (H.B.) 11.6 Protoplanetary disks: Observations + models I (S.W.) 18.6 Gas in disks, molecules, chemistry, keplerian motions (H.B.) 25.6 Protoplanetary disks: Observations + models II (S.W.) 02.7 Accretion, transport processes, local structure and stability (S.W.) 09.7 Planet formation scenarios (S.W.) 16.7 Extrasolar planets: Searching for other worlds (S.W.) 23.7 Summary and open questions (H.B. & S.W.) More Information and the current lecture files: http://www.mpia.de/homes/beuther/lecture_ss07.htmlhttp://www.mpia.de/homes/beuther/lecture_ss07.html and http://www.mpia.de/homes/swolf/vorlesung/sommer2007.htmlhttp://www.mpia.de/homes/swolf/vorlesung/sommer2007.html Emails: beuther@mpia.de, swolf@mpia.de


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