A New Pupil for Detecting Extrasolar Planets

TL;DR

This paper presents a novel optical pupil design that enhances the ability to detect Earth-like exoplanets by creating a deep null in the star's light, combined with correction techniques for mirror imperfections, enabling space telescopes to characterize nearby planets.

Contribution

Introduces a new pupil shape and nulling technique for improved exoplanet detection, integrated with correction methods for optical imperfections in space telescopes.

Findings

Capable of detecting Earth-like planets within 20 parsecs.

Allows atmospheric characterization of nearby exoplanets.

Enhances star-planet contrast using a novel pupil design.

Abstract

The challenge for optical detection of terrestial planet is the 25 magnitude brightness contrast between the planet and its host star. This paper introduces a new pupil design that produces a very dark null along its symmetry axis. By changing the shape of the pupil, we can control the depth and location of this null. This null can be further enhanced by combining this pupil with a rooftop nuller or cateye nuller and an aperture stop. The performance of the optical system will be limited by imperfections in the mirror surface. If the star is imaged with and without the nuller, then we can characterize these imperfections and then correct them with a deformable mirror. The full optical system when deployed on a 6 $\times$ 10 m space telescope is capable of detecting Earthlike planets around stars within 20 parsecs. For an Earthlike planet around a nearby stars (10 parsecs), the telescope can characterize its atmosphere by measuring spectral lines in the 0.3 - 1.3 micron range.