Terrestrial planet detection approaches: externally occulted hybrid coronagraphs

Richard G. Lyon; John A. Gualtieri; Ruslan Belikov

doi:10.1117/12.789787

12 July 2008 Terrestrial planet detection approaches: externally occulted hybrid coronagraphs

Richard G. Lyon, John A. Gualtieri, Ruslan Belikov

Proceedings Volume 7010, Space Telescopes and Instrumentation 2008: Optical, Infrared, and Millimeter; 70101K (2008) https://doi.org/10.1117/12.789787
Event: SPIE Astronomical Telescopes + Instrumentation, 2008, Marseille, France

Abstract

Externally occulted coronagraphs have garnered widespread attention as a potentially viable approach to starlight suppression to enable direct detection and characterization of exo-solar terrestrial planets. Externally occulted coronagraphs consist of a large mask (occulter) in front of the telescope as compared to an internal coronagraph which performs all suppression within the telescope system using combinations of pupil and/or focal plane masks. The advantages of external over internal are that the (i) inner working angle (IWA) is nearly independent of wavelength and (ii) diffracted light is suppressed prior to the telescope; allowing science over a wide spectral band with a conventional telescope with little or no wavefront control. For an internal coronagraph the IWA generally increases with wavelength and scattered/diffracted light levy exquisite tolerances on wavefront, amplitude and polarization errors. An external coronagraph comes with the added complexity and expense of requiring two spacecraft, flying in formation, at separation distances of tens of thousands of kilometers. Re-targeting requires flying one or both spacecraft and aligning them to the target star and hence added fuel and time as well as closed-loop control between them. One approach may be to construct a smaller occulter possibly at closer distances and use it in series with a simple internal coronagraph, i.e. a hybrid, approach. This may simplify requirements on the external occulter but requires more precise tolerances on the telescope system. The question remains as to whether an acceptable balance between the two approaches exists. Herein we look at one approach to designing a hybrid occulter system.

Citation Download Citation

Richard G. Lyon, John A. Gualtieri, and Ruslan Belikov "Terrestrial planet detection approaches: externally occulted hybrid coronagraphs", Proc. SPIE 7010, Space Telescopes and Instrumentation 2008: Optical, Infrared, and Millimeter, 70101K (12 July 2008); https://doi.org/10.1117/12.789787

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
6 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Telescopes

Space telescopes

Coronagraphy

Planets

Stars

Wavefronts

Apodization

Show All Keywords

Keywords/Phrases

Search In:

Publication Years