E. L. Martín (CAB). Direct Imaging of exoplanets and brown dwarfs 3/6

• E. L. Martín (CAB)

Direct Imaging of exoplanets and brown dwarfs

3/6

Formation theories:Gravitational Instability

Sequential accretion:

4/16

Extrasolar Planet Phase Space

Simulations from Ida & Lin

Current harvest of ~350 planets (RV):

empirical constraints on

planetary system formation.

Jupiter & Neptune appear to be the tip

of the “planetary iceberg.”

Extrasolar Planet Phase SpaceExtrasolar Planet Phase Space

Prediction on the habitable planets

No snow line barrier

Barrier withoutenhancement

Barrier & enhancement

14/16Needs to calibrate the efficiency of type I migration

From Doug Lin

15/16

Gaudi

Frequency of Earth

Hot Neptunes around M dwarfs (Ida)

How Will We Know A Planet Supports Life?

Look for evidence of

oxygen

Look for liquid water

Analyze the reflected light

from the planet to see if the

planet has an atmosphere

Look for signs of biological

activity (methane)

And Rule Out Other Explanations?17

Continuous habitable zone => Habplanets

10 mas 100 mas

L. Kaltenegger

FI

Terrestrial Planet Finder (Darwin/TPF)

Visible or thermal-IR?

• Contrast ratio is 1010 in the visible vs. 107 in the thermal-IR

108 in the UV?• Required aperture is

~2 m in the visible vs. 80 m baseline in the IR

≈1010

TPF-CTPF-I

≈107

Visible Spectrum of Earth

Integrated light of Earth, reflected from dark side of moon; Rayleigh, chlorophyll, O2, O3, H2O.

Woolf, Smith, Traub, & Jucks, ApJ 2002; also Arnold et al. 2002

Bloody moon tells how to characterize habplanets

• W. Shakespeare "The moon looks bloody on the earth" [Welsh Captain to the Earl of Salisbury, listing the dread omens that foretell "the death or fall of kings".]

E Pallé et al. Nature 459, 814-816 (2009) doi:10.1038/nature08050

Earth’s visible and near-infrared transmission and reflection spectra.

Summary:

FI may have a niche in UV characterization of habplanets if it achieves contrast of 10-8 in the UV at angular sep. 10 to 100 mas. This science case could be a driver for setting a goal for the size of

the mask.

UV range could give clues on origin of water on habplanets

UV will provide information about size of dust particles in the atmospheres