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Title: ASTROMETRIC JITTER OF THE SUN AS A STAR

Abstract

The daily variation of the solar photocenter over some 11 yr is derived from the Mount Wilson data reprocessed by Ulrich et al. to closely match the surface distribution of solar irradiance. The standard deviations of astrometric jitter are 0.52 {mu}AU and 0.39 {mu}AU in the equatorial and the axial dimensions, respectively. The overall dispersion is strongly correlated with solar cycle, reaching 0.91 {mu}AU at maximum activity in 2000. The largest short-term deviations from the running average (up to 2.6 {mu}AU) occur when a group of large spots happen to lie on one side with respect to the center of the disk. The amplitude spectrum of the photocenter variations never exceeds 0.033 {mu}AU for the range of periods 0.6-1.4 yr, corresponding to the orbital periods of planets in the habitable zone. Astrometric detection of Earth-like planets around stars as quiet as the Sun is not affected by star spot noise, but the prospects for more active stars may be limited to giant planets.

Authors:
 [1];
  1. NASA Exoplanet Science Institute, Caltech, Pasadena, CA 91125 (United States)
Publication Date:
OSTI Identifier:
21455184
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 717; Journal Issue: 2; Other Information: DOI: 10.1088/0004-637X/717/2/1202; Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DAILY VARIATIONS; PLANETS; RADIANT FLUX DENSITY; SOLAR CYCLE; SUN; FLUX DENSITY; MAIN SEQUENCE STARS; STARS; VARIATIONS

Citation Formats

Makarov, V V, Parker, D, and Ulrich, R. K., E-mail: vvm@caltech.ed. ASTROMETRIC JITTER OF THE SUN AS A STAR. United States: N. p., 2010. Web. doi:10.1088/0004-637X/717/2/1202.
Makarov, V V, Parker, D, & Ulrich, R. K., E-mail: vvm@caltech.ed. ASTROMETRIC JITTER OF THE SUN AS A STAR. United States. https://doi.org/10.1088/0004-637X/717/2/1202
Makarov, V V, Parker, D, and Ulrich, R. K., E-mail: vvm@caltech.ed. 2010. "ASTROMETRIC JITTER OF THE SUN AS A STAR". United States. https://doi.org/10.1088/0004-637X/717/2/1202.
@article{osti_21455184,
title = {ASTROMETRIC JITTER OF THE SUN AS A STAR},
author = {Makarov, V V and Parker, D and Ulrich, R. K., E-mail: vvm@caltech.ed},
abstractNote = {The daily variation of the solar photocenter over some 11 yr is derived from the Mount Wilson data reprocessed by Ulrich et al. to closely match the surface distribution of solar irradiance. The standard deviations of astrometric jitter are 0.52 {mu}AU and 0.39 {mu}AU in the equatorial and the axial dimensions, respectively. The overall dispersion is strongly correlated with solar cycle, reaching 0.91 {mu}AU at maximum activity in 2000. The largest short-term deviations from the running average (up to 2.6 {mu}AU) occur when a group of large spots happen to lie on one side with respect to the center of the disk. The amplitude spectrum of the photocenter variations never exceeds 0.033 {mu}AU for the range of periods 0.6-1.4 yr, corresponding to the orbital periods of planets in the habitable zone. Astrometric detection of Earth-like planets around stars as quiet as the Sun is not affected by star spot noise, but the prospects for more active stars may be limited to giant planets.},
doi = {10.1088/0004-637X/717/2/1202},
url = {https://www.osti.gov/biblio/21455184}, journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 717,
place = {United States},
year = {Sat Jul 10 00:00:00 EDT 2010},
month = {Sat Jul 10 00:00:00 EDT 2010}
}