Gaia on-board metrology: basic angle and best focus

Research output: Chapter in Book/Report/Conference proceedingPaper in conference proceeding

Abstract

The Gala payload ensures maximum passive stability using a single material, SiC, for most of its elements. Dedicated metrology instruments are, however, required to carry out two functions: monitoring the basic angle and refocusing the telescope. Two interferometers fed by the same laser are used to measure the basic angle changes at the level of pas (prad, micropixel), which is the highest level ever achieved in space. Two ShackHartmann wavefront sensors, combined with an ad-hoc analysis of the scientific data are used to define and reach the overall best-focus. In this contribution, the systems, data analysis, procedures and performance achieved during commissioning are presented

Details

Authors
  • A. Mora
  • M. Biermann
  • A. G. A. Brown
  • D. Busonero
  • L. Carminati
  • J. M. Carrasco
  • F. Chassat
  • M. Erdmann
  • W. L. M. Gielesen
  • C. Jordi
  • D. Katz
  • R. Kohley
  • W. Loeffler
  • O. Marchal
  • P. Panuzzo
  • G. Seabroke
  • J. Sahlmann
  • E. Serpell
  • I. Serraller
  • F. van Leeuwen
  • W. van Reeven
  • T. C. van den Dool
  • L. L. A. Vosteen
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Astronomy, Astrophysics and Cosmology

Keywords

  • Astrometry, Gaia, metrology, interferometry, basic angle monitor, wavefront sensor, Shack-Hartmann, wavefront reconstruction, centroid, Cramer-Rao, spectral resolution
Original languageEnglish
Title of host publicationSpace Telescopes and Instrumentation 2014: Optical, Infrared, and Millimeter Wave
PublisherSPIE
Pages91430X
Volume9143
Publication statusPublished - 2014
Publication categoryResearch
Peer-reviewedYes
EventConference on Space Telescopes and Instrumentation - Optical, Infrared, and Millimeter Wave - Montreal, Canada
Duration: 2014 Jun 222014 Jun 27

Publication series

Name
Volume9143
ISSN (Print)0277-786X
ISSN (Electronic)1996-756X

Conference

ConferenceConference on Space Telescopes and Instrumentation - Optical, Infrared, and Millimeter Wave
CountryCanada
CityMontreal
Period2014/06/222014/06/27