Pierre BAUDOZ (Paris Observatory) A. Boccaletti, D. Mawet, J. Schneider, G. Tinetti, R. Galicher, C. Cavarroc J. Hough, P. Doel, D. Pinfield, C.-U. Keller, J.-L. Beuzit, S. Udry, M. Ferrari, E. Martin, F. Ménard , E. Sein, & SEE COAST Team …

ULg / CSL / LESIA / LUTH / LUAN / ETH-Zurich / IAP / Obs. Geneva / U. Bern / UCL / ROE / U. Hertfords. / MSSL / SRON / Astron / U. Utrecht / LAOG / ONERA / DLR / U. Vienna / U. Nantes / U. Torino / Astrium

Probing the Extrasolar Planet Diversity with

SEE COAST

SPICA MIR:Old EGPs

Direct Imaging Programs Overview

Space-based

Ground-based

1995 2000 2011 2017-20202008

SEE COASTVis/NIR: Old Jupiter+ Super Earth

Darwin/TPF-I MIR: Earth

TPF-CVis: Earth

JWSTNIR + MIR: Old EGPs

8m + XAOSPHERE / GPI / HiCIAONIR : EGPs young/massive/nearby

30/42m + XAOEPICS/ELTsNIR : EGPs intermediate Old + Super-Earth ?

>2025-30

HSTOpportunity for Space projects

In the Visible

mature giants & Super-Earths

8m + OAVLT, Keck,Gemini, Subaru

4m + OASilla, CFH

We already have targets !!!

From radial velocity surveys : From direct imaging :

More targets to come

• We can anticipate many RV planets at longer periods (giants and tellurics)

• A few accessible from SPHERE/GPI/HiCIAO (1. - 2.3 m) and JWST (2.5 - 28 m)

• Motivation for exploring a different spectral range (in the visible)

angular resolution AND contrast are required:

A small telescope in space can be optimized for exo-planetology

"Super Earth" as a sweet spot : brighter, earth-like notions apply (atmosphere, climate, variations, habitability, …)

What sort of astrophysics on these planets ?

Explore the Diversity with SEE COAST

- Spectra => Chemical composition

Burrows, Sudarsky

- Rayleigh scatterring => pressure, surf. reflectivity

• Spectroscopy

Explore the Diversity

• Spectroscopy• Polarimetry- Polarization=> Clouds / albedo

Jupiter-like planet - Stam et al. 2005Earth-like planet - Stam et al. 2008

cloud

vegetation

oceanA=0

A=1

Explore the Diversity

- Spectral time variation=> variation of temperature=> surface properties

0.45 m

0.75 m

- Polarimetric time variation => surface properties

Cloud free Earth from 0.65 to 0.9 m

50° Phase angle

130°90°

• Spectroscopy• Polarimetry• Variability

Which targets ? (contrast + IWA requirements)

short wavelengths are optimal

longer wavelengths require small IWA coronagraph (2/D)

near IR (1 - 1.2 m)- self luminous planets - T > 800K

10-10 contrast required

A proposal to Cosmic Vision …

✔Submitted in 2007 to ESA Cosmic Vision

Parameter Value

Entrance pupil diameter D > 1.5m

Angular resolution 70 mas @ 0.6 m

Spectral Range 0.4 to 1.2 m

Spectral Resolution R>40

Contrast (after speckle subtraction) @ 2 /D

< 10-9

Contrast (after speckle subtraction) @ 4 /D

< 10-10

Orbit for 6 months visibility, high thermal stability

L2 Lagrangian

Hyperbolic secondary mirror 4,85 m long

Parabolic primary mirror

Two folding mirrors

Focal plane

Coronagraphy: Multi 4QPM

Baudoz et al. 2007, 08

laboratory planetContrast :6.7 10-9bandwidth 20%

Multi 4QPM : Meudon

N phase masks in series => Improves bandwidth as ^NPupil

Telescope

FQPM # 1

FQPM # 3FQPM # 2

Wavefront correction : Coherence

Speckle nullingin a limited FOV with a DM (JPL)

Summary

SEE COAST requires : • High contrast : ≈ 10-10 AND small IWA : ≈ 2 /D

SEE COAST can get : • low res spectra of mature giants < 20pc (< 8 - 10 AU)• colors of a few mature Super Earths < 10pc (< 4 - 5 AU)• possibly Earths around the nearest star ( Cen)• low res spectra of self luminous planets (extension to near IR)

SEE COAST is : • Compatible with general astrophysics (pushing to UV, wide field ?)• Compatible with transit spectroscopy

– additional targets (unresolved planets) & complements IR transit characterization programs

Next steps in the project :• refine some science cases and simulations (statistical analysis) • elaborate optical design with industrial partners (Astrium) + derive tolerances • technological developments in coronagraphy and wavefront control• get prepared for next COSMIC VISION proposal (2010)