Astro2020 Activity, Project of State of the Profession Consideration (APC) White Paper: All-Sky Near Infrared Space Astrometry. State of the Profession Considerations: Development of Scanning NIR Detectors for Astronomy

TL;DR

This paper discusses the development of all-sky near-infrared space astrometry using scanning NIR detectors, addressing Gaia's optical wavelength limitations for observing obscured galactic regions.

Contribution

It presents the state of the profession and explores the development of scanning NIR detectors suitable for space astrometry missions.

Findings

Gaia provides high-precision optical astrometry but is limited in obscured regions.

NIR detectors can overcome Gaia's wavelength limitations for certain galactic studies.

Development of TDI-compatible NIR detectors is crucial for future all-sky infrared astrometry.

Abstract

Gaia is a revolutionary space mission developed by ESA and is delivering 5 parameter astrometry, photometry and radial velocities over the whole sky with astrometric accuracies down to a few tens of micro-arcseconds. A weakness of Gaia is that it only operates at optical wavelengths. However, much of the Galactic centre and the spiral arm regions, important for certain studies, are obscured by interstellar extinction and this makes it difficult for Gaia to deeply probe. This problem can be overcome by switching to the Near Infra-Red (NIR) but this is not possible with silicon CCDs. Additionally, to scan the entire sky and make global absolute parallax measurements the spacecraft must have a constant rotation and this requires the detectors operate in Time Delayed Integration (TDI) mode or similar.