Spectroscopy of extrasolar planets atmosphere Alain Lecavelier des

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Spectroscopy of extrasolar planets atmosphere Alain Lecavelier des Etangs Institut d’Astrophysique de Paris VLST

Spectroscopy of extrasolar planets atmosphere Alain Lecavelier des Etangs Institut d’Astrophysique de Paris VLST Workshop STSc. I Feb. 26 -27, 2004

Alfred Vidal-Madjar Jean-Michel Désert Roger Ferlet Guillaume Hébrard (IAP, Paris) Alain Lecavelier des Etangs

Alfred Vidal-Madjar Jean-Michel Désert Roger Ferlet Guillaume Hébrard (IAP, Paris) Alain Lecavelier des Etangs Institut d’Astrophysique de Paris VLST Workshop STSc. I Feb. 26 -27, 2004

Spectroscopy of extrasolar planets atmosphere • Future is difficult to predict • In 1994,

Spectroscopy of extrasolar planets atmosphere • Future is difficult to predict • In 1994, “When will the first extrasolar planet detected ? ” answers: 2000, 2010… • 1 year ago: detection of OI: “not within the current capabilities” • Prediction: Future is impossible to predict VLST Workshop STSc. I Feb. 26 -27, 2004

Spectroscopy of extrasolar planets atmosphere • What has been done (HST): (description of the

Spectroscopy of extrasolar planets atmosphere • What has been done (HST): (description of the present) 4 UV detections of the bottom and upper atmosphere of HD 209458 b in space, in the UV-optical wavelength range. • With a VLST: (extrapolation to the future from the present) – Large sample of extrasolar planets – Detailed view of planets around nearby stars – Toward Earth and Ocean-like planets VLST Workshop STSc. I Feb. 26 -27, 2004

Transits: a powerful and sensitive method VLST Workshop STSc. I Feb. 26 -27, 2004

Transits: a powerful and sensitive method VLST Workshop STSc. I Feb. 26 -27, 2004

Transit of HD 209458 (Charbonneau et al. 2000) VLST Workshop STSc. I Feb. 26

Transit of HD 209458 (Charbonneau et al. 2000) VLST Workshop STSc. I Feb. 26 -27, 2004

Radial velocity + Occultation depth (Mazeh et al. 2000) HD 209458 b Period =

Radial velocity + Occultation depth (Mazeh et al. 2000) HD 209458 b Period = 3. 524738 days Mass = 0. 69 ± 0. 05 MJupiter Radius = 1. 35 ± 0. 04 RJupiter Density = 0. 35 ± 0. 05 g/cm 3 VLST Workshop STSc. I Feb. 26 -27, 2004

~0. 01% accuracy VLST Workshop STSc. I Feb. 26 -27, 2004

~0. 01% accuracy VLST Workshop STSc. I Feb. 26 -27, 2004

HD 209458 b: Detection of the atmosphere in Na. I (Charbonneau et al. 2002)

HD 209458 b: Detection of the atmosphere in Na. I (Charbonneau et al. 2002) 0. 0232 ± 0. 0057 % VLST Workshop STSc. I Feb. 26 -27, 2004

Y (slit aperture) Search for HI Lyman a (1216 Å) 1214 1215 1216 Wavelength

Y (slit aperture) Search for HI Lyman a (1216 Å) 1214 1215 1216 Wavelength (Å) VLST Workshop STSc. I Feb. 26 -27, 2004 1217

VLST Workshop STSc. I Feb. 26 -27, 2004

VLST Workshop STSc. I Feb. 26 -27, 2004

End of transit Begin of transit Flux Ratio 15 ± 4% Time (hours) VLST

End of transit Begin of transit Flux Ratio 15 ± 4% Time (hours) VLST Workshop STSc. I Feb. 26 -27, 2004

-100 | 100 (km s-1) | Flux ratio Before transit 15 ± 4% During

-100 | 100 (km s-1) | Flux ratio Before transit 15 ± 4% During transit Time (hours) Wavelength (A) • HD 209458 b (1. 35 RJupiter = 96, 500 km) → 1. 6 % absorption Roche Lobe (2. 7 Rplanet = 3. 6 RJupiter) → 10 % absorption Hydrogen: 15 % absorption → 3. 2 Rplanet= 4. 3 RJupiter = 300 000 km → Beyond the Roche Lobe Hydrogen is escaping • Absorption width: – 130 km/s to 100 km/s Vesc = 54 km/s → Beyond escape velocity Hydrogen is escaping The planet is evaporating VLST Workshop STSc. I Feb. 26 -27, 2004

Escape rate estimate How much for 15% absorption? VLST Workshop STSc. I Feb. 26

Escape rate estimate How much for 15% absorption? VLST Workshop STSc. I Feb. 26 -27, 2004

Escape rate > 1010 g/s VLST Workshop STSc. I Feb. 26 -27, 2004

Escape rate > 1010 g/s VLST Workshop STSc. I Feb. 26 -27, 2004

An extended upper atmosphere around the extrasolar planet HD 209458 b A. Vidal-Madjar (IAP)

An extended upper atmosphere around the extrasolar planet HD 209458 b A. Vidal-Madjar (IAP) A. Lecavelier des Étangs (IAP) J. -M. Désert (IAP) G. E. Ballester (Univ. Arizona) R. Ferlet (IAP) G. Hébrard (IAP) M. Mayor (Obs. Genève) Nature 422, 143 (2003) VLST Workshop STSc. I Feb. 26 -27, 2004

HST G 140 L Observations Oct-Nov 2003 • Fig 1 VLST Workshop STSc. I

HST G 140 L Observations Oct-Nov 2003 • Fig 1 VLST Workshop STSc. I Feb. 26 -27, 2004

Terrestrial airglow Stellar spectrum Si. III H I Lyman a OI VLST Workshop STSc.

Terrestrial airglow Stellar spectrum Si. III H I Lyman a OI VLST Workshop STSc. I Feb. 26 -27, 2004 C II Stellar continuum

Confirmation of the HI absorption • Fig 2 a HI Lyman a Out of

Confirmation of the HI absorption • Fig 2 a HI Lyman a Out of transit In transit Si III ~5 % Wavelength (Å) VLST Workshop STSc. I Feb. 26 -27, 2004

Detection of Carbon and Oxygen Out of Transit In Transit C II OI Vidal-Madjar

Detection of Carbon and Oxygen Out of Transit In Transit C II OI Vidal-Madjar et al. 2004 (astro-ph/0401457) ~13 % ~8 % ± 4. 5 % ± 3. 5 % Wavelength (Å) VLST Workshop STSc. I Feb. 26 -27, 2004

Consequence Vidal-Madjar et al. (2004 astro-ph/0401457) • Oxygen and carbon are also present in

Consequence Vidal-Madjar et al. (2004 astro-ph/0401457) • Oxygen and carbon are also present in the upper atmosphere of HD 209458 b • They are carried out by the hydrogen flow: HYDRODYNAMICAL ESCAPE ( « BLOW-OFF » ) VLST Workshop STSc. I Feb. 26 -27, 2004

More can be done • Last observations must be confirmed (2. 5 s) •

More can be done • Last observations must be confirmed (2. 5 s) • Other species are likely detectable with HST Cycle 13 proposal… VLST Workshop STSc. I Feb. 26 -27, 2004

Planets to be discovered Today ~120 planets know Rad. Vel. 10 m/s <(present) 2003

Planets to be discovered Today ~120 planets know Rad. Vel. 10 m/s <(present) 2003 1 m/s Harps (2003 HARPS) 2003 COROT (2006) KEPLER (2007/8) VLST Workshop STSc. I Feb. 26 -27, 2004

A large number of targets for the VLST • ≥ 7% planet / star

A large number of targets for the VLST • ≥ 7% planet / star • 15% « Hot Jupiter » / planet 1% « Hot Jupiter » / star • 10% transiting planet / « Hot Jupiter » 0. 1% transit / star • 10, 000 G stars (V≤ 8) 10 « Hot Jupiter » transits on stars V≤ 8 • 85, 000 G stars (V≤ 10) 85 transits on V≤ 10 • 300, 000 G stars (V≤ 12) 300 transits on V≤ 12 VLST Workshop STSc. I Feb. 26 -27, 2004

Planets with Earth-like orbital distances For d=1 AU, Probability Transit R*/a=0. 5% ~30% of

Planets with Earth-like orbital distances For d=1 AU, Probability Transit R*/a=0. 5% ~30% of known planets within 0. 5 -1. 5 AU 0. 15% 1 AU-transiting planet per planetary system ~30 transiting planet on Earth-like orbit around a G- type star V≤ 12 (For giant planets only…) IF 25% low-mass planet/star ~30 transiting low-mass planet on Earth-like orbit around a G-type star V≤ 10 VLST Workshop STSc. I Feb. 26 -27, 2004

Summary of detection capabilities on V≤ 8 stars HST VLST Height species FUV 4%

Summary of detection capabilities on V≤ 8 stars HST VLST Height species FUV 4% 0. 4% 10, 000 km H, C, O, CO, O 2 NUV 1% 0. 1% 2, 500 km Fe, Mg, et al. ; CO, NO Bands <0. 1% <0. 01% <250 km O 3 Opt. 0. 01% 0. 001% 25 km Na, K, Li, OH (3090 A) NUV-Opt Time scan VLST Workshop STSc. I Feb. 26 -27, 2004

Time-scan • HST observations used a total of ~100 -200 minutes exposures during transits.

Time-scan • HST observations used a total of ~100 -200 minutes exposures during transits. VLST gives diagnostics in few minutes exposure • Tingress=80 (Rp/RJup) (a/1 AU) ½ minutes THD 209458= 22 minutes • Scan of the planets “weather” during the partial occultation phases (ingress, egress): VLST Workshop STSc. I Feb. 26 -27, 2004

Temperate Uranus (Ocean-planets) (A. Leger 2003) • Scale height: H = 250 (T/300 K)

Temperate Uranus (Ocean-planets) (A. Leger 2003) • Scale height: H = 250 (T/300 K) (Rp/REarth)2 (Mp/MEarth)-1 m km HO 2 =8 km on the Earth • Uranus parameter (Rp=4 REarth , Mp=15 MEarth) same scale height: HO 2 =8 km Expected occultation depth ~0. 001% … Likely detectable on broad-bands. VLST Workshop STSc. I Feb. 26 -27, 2004

Scientific goals • Structures of the atmosphere of extra-solar planets (composition, dust/clouds/haze content, “weather”).

Scientific goals • Structures of the atmosphere of extra-solar planets (composition, dust/clouds/haze content, “weather”). • Interaction between planets and stars • Evolution of planets atmosphere (escape, fate of remaining core. . ) • Probe of new kinds of planets (temperate Uranus, evaporation-modified hot-Jupiters) • Life ? (improve our knowledge of habitable planets) VLST Workshop STSc. I Feb. 26 -27, 2004

This picture shows also the Earth atmosphere with emission from hydrogen and oxygen at

This picture shows also the Earth atmosphere with emission from hydrogen and oxygen at high (HST) altitude where the C/O is obviously very low. Terrestrial airglow Stellar spectrum Si. III H I Lyman a OI VLST Workshop STSc. I Feb. 26 -27, 2004 C II Stellar continuum

• END VLST Workshop STSc. I Feb. 26 -27, 2004

• END VLST Workshop STSc. I Feb. 26 -27, 2004