RUANE , Garreth

Direct imaging is the primary technique currently used to detect young and warm exoplanets and understand their formation scenarios. The extreme flux r atio b etween a n e xoplanet a nd i ts h ost s tar r equires t he u se of coronagraphs to attenuate the starlight and create high contrast images. However, their performance is limited by...

Context. Gaps in circumstellar disks can signal the existence of planetary perturbers, making such systems preferred targets for direct imaging observations of exoplanets. Aims: Being one of the brightest and closest stars to the Sun, the photometric standard star Vega hosts a two-belt debris disk structure. Together with the fact that its...

We aim to inform Astro2020 of the status of coronagraph technology for use with a space-based segmented and/or partially obscured primary mirror. Our design and modeling study has determined that multiple coronagraph architectures can achieve the necessary performance. Some preliminary observatory requirements appear challenging but achievable.

International audience

Instrumentation techniques in the field of direct imaging of exoplanets have greatly advanced over the last two decades. Two of the four NASA-commissioned large concept studies involve a high-contrast instrument for the imaging and spectral characterization of exo-Earths from space: LUVOIR and HabEx. This whitepaper describes the status of 8...

International audience

International audience

International audience

The Coronagraph Instrument (CGI) for NASA's Wide Field Infrared Survey Telescope (WFIRST) will constitute a dramatic step forward for high-contrast imaging, integral field spectroscopy, and polarimetry of exoplanets and circumstellar disks, aiming to improve upon the sensitivity of current ground-based direct imaging facilities by 2-3 orders of...

Recent Atacama Large Millimeter/submillimeter Array (ALMA) observations of protoplanetary disks in the millimeter continuum have shown a variety of radial gaps, cavities, and spiral features. These substructures may be signposts for ongoing planet formation, and therefore these systems are promising targets for direct imaging planet searches in...

Our ability to answer scientific questions about exoplanets hinges on satisfying an age-old astronomical requirement: a sufficient sample size. Thus, the yield of exoplanets is critical to understanding the scientific impact of future missions. We discuss how the yield of directly-imaged exoplanets depends on mission scale and survey design.

Exoplanet science is one of the most thriving fields of modern astrophysics. A major goal is the atmospheric characterization of dozens of small, terrestrial exoplanets in order to search for signatures in their atmospheres that indicate biological activity, assess their ability to provide conditions for life as we know it, and investigate...