The Gaia Project - technique, performance and status

TL;DR

Gaia is an ESA satellite mission designed to perform highly precise astrometric measurements of about one billion stars, providing detailed positional, brightness, and spectral data to advance our understanding of the galaxy.

Contribution

This paper details the techniques, performance metrics, and current status of the Gaia mission, highlighting its unprecedented accuracy and self-calibration methods.

Findings

Achieved 20 microarcsecond accuracy at 15th magnitude

Successfully inferred telescope geometry and attitude from measurements

Collected comprehensive astrometric data for over a billion stars

Abstract

Gaia is a satellite mission of the ESA, aiming at absolute astrometric measurements of about one billion stars (all stars down to 20th magnitude, with unprecedented accuracy. Additionally, magnitudes and colors will be obtained for all these stars, while radial-velocities and spectral properties will be determined only for bright objects (V<17.5). At 15th magnitude Gaia aims at an angular accuracy of 20 microarcseconds (muas). This goal can only be reached if the geometry of the telescopes, the detectors, and the pointing of Gaia at each moment ("attitude") can be inferred from the Gaia measurements itself with muas accuracy.