Astronomy & Telescopes

A Pathfinder for Imaging Extrasolar Earths from the Ground

By Keith Cowing
June 7, 2019
Filed under
A Pathfinder for Imaging Extrasolar Earths from the Ground
Two near-infrared images of the HR 8799 system. The left image is from a leading conventional (facility) AO system on the Keck telescope; on the right is a SCExAO/CHARIS image. SCExAO/CHARIS produces higher signal-to-noise detections of HR 8799 cd and a detection of HR 8799 e.

The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) project is an instrument on the Subaru telescope that is pushing the frontiers of what is possible with ground-based high-contrast imaging of extrasolar planets.

The system features key breakthroughs in wavefront sensing and coronagraphy to yield extremely high Strehl ratio corrections and deep planet-to-star contrasts, even for optically faint stars. SCExAO is coupled to a near-infrared integral field spectrograph — CHARIS — yielding robust planet spectral characterization.

In its first full year of operations, SCExAO has already clarified the properties of candidate companions around κ And, LkCa 15, and HD 163296, showing the former to be a likely low-gravity, planet-mass object and the latter two to be misidentified disk signals. SCExAO’s planet imaging capabilities in the near future will be further upgraded; the system is emerging as a prototype of the kind of dedicated planet-imaging system that could directly detect an Earth-like planet around a nearby low-mass star with Extremely Large Telescopes like the Thirty Meter Telescope.

Thayne Currie (NASA/Ames, Subaru)
(Submitted on 5 Jun 2019)
Comments: 4 pages, 1 figure; author’s original submitted draft of article edited and published in Nature Astronomy
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM)
Cite as: arXiv:1906.02214 [astro-ph.EP] (or arXiv:1906.02214v1 [astro-ph.EP] for this version)
Submission history
From: Thayne Currie
[v1] Wed, 5 Jun 2019 18:00:22 UTC (514 KB)

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