Exploration of Millisecond Exposures for Exoplanet Imaging

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

This proposal will perform the exploratory work needed to develop millisecond imaging technologies as a viable tool for ultra-high contrast astronomy. The direct application of this work is to the development and utilization of the next generation of extremely large telescopes, currently under construction, that will be involved in direct imaging and characterization of extra-solar planets. The discovery, classification, and characterization of extra-solar planets has stirred the imagination of lay people and professional astronomers alike. The discovery and characterization of an earth like planet, with atmospheric chemical signatures of life processes, would have a profound impact on humanity. Adaptive Optics (AO) systems have made significant improvements in both the imaging spatial resolution and contrast available to ground-based telescopes. Although an AO system attempts to fully correct for atmospheric-induced wavefront distortions, a real-world AO system does an imperfect job, resulting in the "AO residual", a set of speckles in the image plane that appear and disappear at millisecond time-scales. It has been shown that these speckles are a major limitation to high-contrast imaging, such as that involved in directly imaging exoplanets. In the proposed formulation, the science camera operates synchronously with the wavefront sensor (WFS), so that the science camera records a speckle pattern that corresponds to the wavefront measured by the WFS. The resulting millisecond exposures provide an information-rich dataset containing a random AO residual, measured by the WFS, that effectively interrogates the optical system and provides new information about the "non-common path aberrations", which, when corrected, can significantly improve ultra-high contract astronomical imaging.