SETI & Technosignatures

Model Of The Search For Extraterrestrial Intelligence With Coronagraphic Imaging

By Keith Cowing
Press Release
September 10, 2019
Filed under
Model Of The Search For Extraterrestrial Intelligence With Coronagraphic Imaging
A cartoon diagram of the OIRSETI geometry considered in this work

We present modeled detection limits of the Gemini Planet Imager (GPI) and the Wide-Field Infrared Space Telescope (WFIRST) to an optical and infrared laser which could be used by an extraterrestrial civilization to signal their presence.

GPI and WFIRST could utilize a coronagraph to search for extraterrestrial intelligence (SETI) in the present and future. We use archival data for GPI stars and simulated WFIRST observations to find the detectable flux ratio of a laser signal to residual scattered starlight around the target star. This flux ratio is then converted to detectable power as a function of distance from the parent star.

For GPI, we assume a monochromatic laser wavelength of 1.55 μm, and a wavelength of 575 nm for WFIRST. We assume the lasers are projected through a 10-m aperture, and that the intensity of the laser beam follows a Gaussian profile. Our analysis is performed on 6 stars with spectral types later than F within 20 pc (with an emphasis on solar analogs at different distances). The most notable result is the detection limit for τ Ceti, a G5V star with four known exoplanets, two of those within the habitable zone (HZ). The result shows that a 24 kW laser is detectable from τ Ceti from outside of the HZ with GPI and a 7.3 W laser is detectable from within τ Ceti’s HZ by WFIRST.

Christina L. Vides, Bruce Macintosh, Breanna A. Binder, Robert J. De Rosa, Jean-Baptiste Ruffio, Dmitry Savransky
(Submitted on 9 Sep 2019)

Comments: Accepted to AJ, 10 pages, 5 figures, 4 tables
Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)
Cite as: arXiv:1909.04128 [astro-ph.IM] (or arXiv:1909.04128v1 [astro-ph.IM] for this version)
Submission history
From: Christina Vides
[v1] Mon, 9 Sep 2019 20:00:15 UTC (508 KB)

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