Hostname: page-component-8448b6f56d-mp689 Total loading time: 0 Render date: 2024-04-19T02:24:58.241Z Has data issue: false hasContentIssue false

Simulating Gaia observations and on-ground reconstruction

Published online by Cambridge University Press:  01 October 2007

E. Masana
Affiliation:
Departament d'Astronomia i Meteorologia. Universitat de BarcelonaAv. Diagonal 647, E 08028 Barcelona, Spain email: emasana@am.ub.es
C. Fabricius
Affiliation:
Departament d'Astronomia i Meteorologia. Universitat de BarcelonaAv. Diagonal 647, E 08028 Barcelona, Spain email: emasana@am.ub.es
J. Torra
Affiliation:
Departament d'Astronomia i Meteorologia. Universitat de BarcelonaAv. Diagonal 647, E 08028 Barcelona, Spain email: emasana@am.ub.es
J. Portell
Affiliation:
Departament d'Astronomia i Meteorologia. Universitat de BarcelonaAv. Diagonal 647, E 08028 Barcelona, Spain email: emasana@am.ub.es
J. Catañeda
Affiliation:
Departament d'Astronomia i Meteorologia. Universitat de BarcelonaAv. Diagonal 647, E 08028 Barcelona, Spain email: emasana@am.ub.es
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

On a daily basis the Gaia telemetry data (some 30 GB) must be stored and treated in order to reconstruct the actual observations. This initial data treatment processes all newly arrived telemetry and various pieces of auxiliary data. The first part of the process is merely a reformatting to create raw objects for permanent storage in the raw data base (some 40 TB at the end of the mission). The next part is to analyze the data to derive initial values for the observables, e.g. transit times and fluxes, producing intermediate objects. Finally, the intermediate objects are matched with sources in the data base, linking all the observations of a given source.

To check the initial data treatment algorithm we use simulations of the telemetry stream provided by GASS, the Gaia System Simulator. GASS simulates astrometric, photometric and radial velocity data, using models of the satellite and on-board instruments, as well as the models of different of objects observed by Gaia (stars, galaxies, solar system objects, . . .). On the other hand, the initial data treatment allows us to validate the data generated by GASS, which are used too to check other algorithms like the First Look or the Astrometric Global Iterative Solution (AGIS).

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2008