Extrasolar Planets

The Value Of Astrometry For Exoplanet Science

By Keith Cowing
Press Release
March 14, 2018
Filed under
The Value Of Astrometry For Exoplanet Science

Exoplanets mass measurements will be a critical next step to assess the habitability of Earth-like planets: a key aspect of the 2020 vision in the previous decadal survey and also central to NASA’s strategic priorities.

Precision astrometry delivers measurement of exoplanet masses, allowing discrimination of rocky planets from water worlds and enabling much better modeling of their atmosphere improving species retrieval from spectroscopy. The scientific potential of astrometry will be enormous. The intrinsic astrophysical noise floor set by star spots and stellar surface activity is about a factor of ten more benign for astrometry than for the more established technique of Radial Velocity, widening the discovery region and pushing detection thresholds to lower masses than previously possible. On the instrumental side, precision astrometry is limited by optical field distortion and detector calibration issues. Both technical challenges are now being addressed successfully in the laboratory. However, we have identified the need to continue these technology development efforts to achieve sub-microarcsecond astrometry precision necessary for detection and characterization of Earth-like planets around nearby FGK stars.

The international community has realized the importance of astrometry, and various astrometry missions have been proposed and under development, with a few high profile missions now operational. We believe that it is vital for the U.S. scientific community to participate in the development of these new technologies and scientific discoveries. We recommend exploring alternatives to incorporate astrometric capabilities into future exoplanet flagship missions such as HABEX and LUVOIR, substantially increasing the scientific return associated with the expected yield of earth-like planets to be recovered.

Eduardo Bendek, Mark Marley, Michael Shao, Olivier Guyon, Ruslan Belikov, Peter Tuthill
(Submitted on 13 Mar 2018)

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)
Cite as: arXiv:1803.04642 [astro-ph.IM] (or arXiv:1803.04642v1 [astro-ph.IM] for this version)
Submission history
From: Eduardo Bendek
[v1] Tue, 13 Mar 2018 06:17:09 GMT (582kb)

SpaceRef co-founder, Explorers Club Fellow, ex-NASA, Away Teams, Journalist, Space & Astrobiology, Lapsed climber.