Gaia in 2003
Author: Michael Perryman
Published in: unpublished - project document
Summary: This document summarises the status of the Gaia project at the end of 2003, describing the progress achieved in 2003, and summarising the major ongoing and planned activities in both the scientific and technical areas. It gives references to technical notes prepared by the Gaia scientific community during the year
Available to download from this site:[pdf, 400k]

Gaia in 2002
Author: Michael Perryman
Published in: unpublished - project document
Summary: This document summarises the status of the Gaia project at the end of 2002, describing the progress achieved in 2002, and summarising the major ongoing and planned activities in both the scientific and technical areas. It gives references to technical notes prepared by the Gaia scientific community during the year
Available to download from this site:[pdf, 297k]

Gaia: Composition, Formation and Evolution of the Galaxy
Authors: M.A.C. Perryman, K. de Boer, G. Gilmore, et al
Published in: A&A, 369, 339-363 (2001)
Summary: The scientific case and technical design description on which the mission was accepted within ESA's scientific programme. Note that the design details have been superseded, although the essential instrument principles and design objectives remain unaffected.
See ADS Astronomy Abstract Service entry for links to electronic version. Also available from astro-ph.
An extract of the original Study Science Report covering the scientific case is available online or can be downloaded as a pdf file.

Reference Systems, Conventions and Notations for Gaia
Author: U. Bastian
Published in: unpublished - project document
Summary: This document brings together the terminology and naming conventions used by the various working groups and by industry with a view to harmonising the language used to describe the basic aspects of the Gaia mission and the measurements to be performed with it.
Available to download from livelink [restricted access].

For a complete list of Gaia-related articles and papers use the search astro-ph or search ADS facilities (see right-hand menu.)

Aberration in proper motions
Author: J. Kovalevsky
Published in: Astronomy and Astrophysics, v.404, pp.743-747 (2003)
Summary: Approved space astrometric missions (SIM, Gaia) are aiming at a few microarcseconds per year precision in yearly proper motions and even less than a microarcsecond in the definition of an extragalactic reference frame. At such a level of accuracy, the curvature of stellar orbits around the center of the Galaxy cannot be neglected. The curvature of the Solar System barycentric motion induces a time-dependent component of the aberration, which has the properties of an apparent proper motion of the galaxies. The paper gives the proofs and the formulae permitting one to compute this aberration in proper motions. The conclusion is that, at this high level of accuracy, one should present the astrometric data in a galacto-centric rather than in a barycentric reference frame.
See ADS Astronomy Abstract Service entry for links to electronic version.

Close encounters of asteroids before and during the ESA Gaia mission
Authors: A. Fienga, J.-F. Bange, A. Bec-Borsenberger, W. Thuillot
Published in: Astronomy & Astrophysics, v. 406, pp. 751-758 (2003)
Summary: Observations of close encounters of asteroids is a powerful method to determine their masses. Included in the this paper are lists of single and multiple phenomena spanning 2010-2022 and only accessible by space astrometry. These last encounters may be observed during the ESA Gaia space mission.
See ADS Astronomy Abstract Service entry for links to electronic version.

Supernovae with super-Hipparcos
Authors: V.A. Belokurov, N.W. Evans
Published in: MNRAS, Volume 341, pp. 569-576 (2003)
Summary: This paper calculates that some 20,000 supernovae will be observable by Gaia, of which 14,300 are Type Ia, 1400 are Type Ib and 5700 are Type II. Of these, the number caught before maximum are: 6300, 500 and 1700 respectively, with some 5 alerts issued per day, and a measurement accuracy offering opportunities for the identification of progenitors in nearby galaxies.
See astro-ph entry for links to postscript and pdf versions of the paper.

A Practical Relativistic Model for Microarcsecond Astrometry in Space
Author: S.A. Klioner
Published in: The Astronomical Journal, v. 125(3), pp. 1580-1597 (2003)
Summary: The paper develops a practical model for relativistic reduction of positional observations with an accuracy of 1 microarcsec. All relativistic effects that are caused by the gravitational field of the solar system and are of practical importance for this accuracy level are thoroughly calculated and discussed.
See ADS Astronomy Abstract Service entry for links to electronic version.

Observations of solar system objects with Gaia. I. Detection of NEOS
Author: F. Mignard
Published in: Astronomy & Astrophysics, v. 393, pp. 727-731 (2002)
Summary: This paper discusses the observability by Gaia of solar system objects belonging to the group of near-earth objects. Most objects with a diameter larger than 2 km will be observed at least five times by GAIA and much more often for larger bodies. The detection survey will be 50% complete for objects of diameter 1 km, while smaller objects (D < 0.5 km) will usually escape detection.
See ADS Astronomy Abstract Service entry for links to electronic version.

Astrometric microlensing with the Gaia satellite
Authors: V.A. Belokurov, N.W. Evans
Published in: MNRAS, Volume 331, pp. 649-665 (2002)
Summary: The paper estimates the number of sources that will experience a significant variation in the centroid position during the mission lifetime (about 25,000), and assesses the number for which masses can be recovered, the number of photometric microlensing events, and the effect of microlensing noise on the astrometric results.
See astro-ph entry for links to postscript and pdf versions of the paper.