Context : Measurements of the frequency with which short-period planets occur around main sequence stars allows a direct prediction of the number and types of such planets that will be amenable to characterization by high-contrast instruments on future giant segmented-mirror telescopes ( GSMTs ) .
Adopting conservative assumptions , I predict of order 10 planets with radii R _ { P } = 1 - 8 R _ { \Earth } and equilibrium temperatures \lesssim 400 K should be accessible around stars within 8 pc of the Sun .
These numbers are roughly the same for both near-infrared observations of scattered starlight and mid-infrared observations of planetary thermal emission , with the latter observations demonstrating greater relative sensitivity to smaller and cooler planets .
Adopting the conservative assumption that planets with R _ { P } = 1 - 2 R _ { \Earth } and 2 - 4 R _ { \Earth } occur with equal frequency , I predict a 40 % chance that a planet with R _ { P } = 1 - 2 R _ { \Earth } and equilibrium temperature 200–250 K will accessible to high-contrast thermal infrared characterization ; this would be a compelling object for further study .
To validate these predictions , more detailed analyses are needed of the occurrence frequencies of low-mass planets around M dwarfs , both in the Kepler field and in the solar neighborhood .
Several planets already discovered by radial velocity surveys will be accessible to near-infrared high-contrast GSMT observations , including the low-mass planets \alpha Cen Bb and ( depending on their albedos ) GJ 139c and d , GJ 876b and c , and \tau Cet b , c , and d ; \tau Cet f would be amenable to thermal infrared characterization .
Further efforts to model the near-infrared reflectance and mid-infrared emission of these and other short-period planets are clearly warranted , and will pave the way for the interpretation of future high-contrast characterization of a variety of planets around the nearest stars .

Aims :

Methods :

Results :

Conclusions :