Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-17T16:16:27.563Z Has data issue: false hasContentIssue false

The Tycho-Gaia Astrometric Solution

Published online by Cambridge University Press:  07 March 2018

Lennart Lindegren*
Affiliation:
Lund Observatory, Department of Astronomy and Theoretical Physics Lund University, Box 43, SE-22100 Lund, Sweden email: lennart@astro.lu.se
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.

Gaia DR1 is based on the first 14 months of Gaia's observations. This is not long enough to reliably disentangle the parallax effect from proper motion. For most sources, therefore, only positions and magnitudes are given. Parallaxes and proper motions were nevertheless obtained for about two million of the brighter stars through the Tycho-Gaia astrometric solution (TGAS), combining the Gaia observations with the much earlier Hipparcos and Tycho-2 positions. In this review I focus on some important characteristics and limitations of TGAS, in particular the reference frame, astrometric uncertainties, correlations, and systematic errors.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2018 

References

Arenou, F., Luri, X., Babusiaux, C., Fabricius, C., Helmi, A., et al. 2017, A&A, 599, A50 Google Scholar
Arias, E. F., Charlot, P., Feissel, M., & Lestrade, J.-F., 1995, A&A, 303, 604 Google Scholar
Fey, A. L., Gordon, D., Jacobs, C. S., Ma, C., Gaume, R. A., Arias, E. F., Bianco, G., Boboltz, D. A., et al. 2015, AJ, 150, 58 Google Scholar
Gaia Collaboration, Brown, A. G. A., Vallenari, A., Prusti, T., de Bruijne, J. H. J., Mignard, F., Drimmel, R., Babusiaux, C., et al. 2016, A&A, 595, A2 Google Scholar
Gaia Collaboration, Prusti, T., de Bruijne, J. H. J., Brown, A. G. A., Vallenari, A., Babusiaux, C., Bailer-Jones, C. A. L., Bastian, U., et al. 2016, A&A, 595, A1 Google Scholar
Høg, E., Fabricius, C., Makarov, V. V., et al. 2000, A&A, 355, L27 Google Scholar
Kovalevsky, J., Lindegren, L., Perryman, M. A. C., Hemenway, P. D., Johnston, K. J., Kislyuk, V. S., Lestrade, J. F., Morrison, L. V., et al. 1997, A&A, 323, 620 Google Scholar
Lindegren, L., Lammers, U., Bastian, U., Hernández, J., Klioner, S., et al. 2016, A&A, 595, A4 Google Scholar
Michalik, D., Lindegren, L., Hobbs, D., & Lammers, U., 2014, A&A, 571, A85 Google Scholar
Michalik, D., Lindegren, L., & Hobbs, D., 2015a, A&A, 574, A115 Google Scholar
Michalik, D. & Lindegren, L., 2016, A&A, 586, A26 Google Scholar
Mignard, F., 2009, unpublished technical note GAIA-C3-TN-OCA-FM-040, http://www.rssd.esa.int/doc_fetch.php?id=2939272 Google Scholar
van Leeuwen, F., 2007, Hipparcos, the New Reduction of the Raw Data, Astrophysics and Space Science Library, Vol. 350Google Scholar