Fainter and closer: finding planets by symmetry breaking

TL;DR

The paper introduces a novel method using a rotating eccentric pupil mask to break symmetry in residual speckle patterns, enabling detection of faint planets close to bright stars beyond traditional limits.

Contribution

It proposes a new symmetry-breaking technique with a rotating pupil mask to improve direct imaging of exoplanets by enhancing contrast and proximity detection.

Findings

Can detect planets six magnitudes fainter than their star.

Achieves detection within 2-3 times the diffraction limit.

Reduces stellar background brightness by five magnitudes.

Abstract

Imaging of planets is very difficult, due to the glare from their nearby, much brighter suns. Static and slowly-evolving aberrations are the limiting factors, even after application of adaptive optics. The residual speckle pattern is highly symmetrical due to diffraction from the telescope's aperture. We suggest to break this symmetry and thus to locate planets hidden beneath it. An eccentric pupil mask is rotated to modulate the residual light pattern not removed by other means. This modulation is then exploited to reveal the planet's constant signal. In well-corrected ground-based observations we can reach planets six stellar magnitudes fainter than their sun, and only 2-3 times the diffraction limit from it. At ten times the diffraction limit, we detect planets 16 magnitudes fainter. The stellar background drops by five magnitudes.