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The astrometric instrument of Gaia: Principles

Lindegren, Lennart LU (2005) Symposium - The Three-Dimensional Universe with Gaia In European Space Agency, (Special Publication) ESA SP 576. p.29-34
Abstract
Compared with Hipparcos, Gaia will give an enormous improvement in accuracy, completeness and number of stars: about two orders of magnitude in accuracy, four orders in number, and a completeness limit that is 12 magnitudes fainter. How is all this possible? The answer is: by a combination of many factors, the most important being bigger and more efficient detectors, and bigger optics. The method of astrometric measurements by Gaia is described from first principles, and the fundamental limitations explained in terms of physics (diffraction and photon noise), geometry, temporal sampling and reference frames. Although Gaia is basically a self-calibrating instrument, things have to be stable enough over time scales that are long enough for... (More)
Compared with Hipparcos, Gaia will give an enormous improvement in accuracy, completeness and number of stars: about two orders of magnitude in accuracy, four orders in number, and a completeness limit that is 12 magnitudes fainter. How is all this possible? The answer is: by a combination of many factors, the most important being bigger and more efficient detectors, and bigger optics. The method of astrometric measurements by Gaia is described from first principles, and the fundamental limitations explained in terms of physics (diffraction and photon noise), geometry, temporal sampling and reference frames. Although Gaia is basically a self-calibrating instrument, things have to be stable enough over time scales that are long enough for the calibrations to be carried out, and the corresponding requirements are outlined. To achieve microarcsecond accuracy is technically extremely demanding, but feasible with a clever and careful design of the instrument. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
keywords
Accuracy, Parallax, Gaia, ESA
in
European Space Agency, (Special Publication) ESA SP
volume
576
pages
29 - 34
publisher
European Space Agency
conference name
Symposium - The Three-Dimensional Universe with Gaia
external identifiers
  • wos:000229610000004
  • scopus:23744451792
ISSN
0379-6566
1609-042X
language
English
LU publication?
yes
id
8590bd9a-ee64-49e0-bd43-8e28ea3c5722 (old id 615555)
alternative location
http://www.rssd.esa.int/SA/GAIA/docs/Gaia_2004_Proceedings/Gaia_2004_Proceedings_29.pdf
date added to LUP
2007-11-25 15:05:36
date last changed
2017-03-26 03:42:47
@inproceedings{8590bd9a-ee64-49e0-bd43-8e28ea3c5722,
  abstract     = {Compared with Hipparcos, Gaia will give an enormous improvement in accuracy, completeness and number of stars: about two orders of magnitude in accuracy, four orders in number, and a completeness limit that is 12 magnitudes fainter. How is all this possible? The answer is: by a combination of many factors, the most important being bigger and more efficient detectors, and bigger optics. The method of astrometric measurements by Gaia is described from first principles, and the fundamental limitations explained in terms of physics (diffraction and photon noise), geometry, temporal sampling and reference frames. Although Gaia is basically a self-calibrating instrument, things have to be stable enough over time scales that are long enough for the calibrations to be carried out, and the corresponding requirements are outlined. To achieve microarcsecond accuracy is technically extremely demanding, but feasible with a clever and careful design of the instrument.},
  author       = {Lindegren, Lennart},
  booktitle    = {European Space Agency, (Special Publication) ESA SP},
  issn         = {0379-6566},
  keyword      = {Accuracy,Parallax,Gaia,ESA},
  language     = {eng},
  pages        = {29--34},
  publisher    = {European Space Agency},
  title        = {The astrometric instrument of Gaia: Principles},
  volume       = {576},
  year         = {2005},
}