Spotting Stellar Activity Cycles in Gaia Astrometry

Abstract

Astrometry from Gaia will measure the positions of stellar photometric centroids to unprecedented precision. We show that the precision of Gaia astrometry is sufficient to detect starspot-induced centroid jitter for nearby stars in the Tycho-Gaia Astrometric Solution (TGAS) sample with magnetic activity similar to the young G-star KIC 7174505 or the active M4 dwarf GJ 1243, but is insufficient to measure centroid jitter for stars with Sun-like spot distributions. We simulate Gaia observations of stars with 10 year activity cycles to search for evidence of activity cycles, and find that Gaia astrometry alone likely can not detect activity cycles for stars in the TGAS sample, even if they have spot distributions like KIC 7174505. We review the activity of the nearby low-mass stars in the TGAS sample for which we anticipate significant detections of spot-induced jitter.

Accepted for publication in MNRAS, Feb 27, 2018

References in corpus (17)

• The NumPy array: a structure for efficient numerical computation
• The Gaia mission
• Large-scale magnetic topologies of late M dwarfs
• Astrometric exoplanet detection with Gaia
• Magnetic Cycles and Rotation Periods of Late Type Stars from photometric time series
• Inverting Phase Functions to Map Exoplanets
• The Tycho-Gaia astrometric solution. How to get 2.5 million parallaxes with less than one year of Gaia data
• The solar chromosphere at high resolution with IBIS. I. New insights from the Ca II 854.2 nm line
• The Starspots of HAT-P-11: Evidence for a Solar-like Dynamo
• High Dispersion Spectroscopy of Solar-type Superflare Stars. II. Stellar Rotation, Starspots, and Chromospheric Activities
• The Ca II infrared triplet's performance as an activity indicator compared to Ca II H and K
• Proxima Centauri as a Benchmark for Stellar Activity Indicators in the Near Infrared
• Chromospheric Activity of HAT-P-11: an Unusually Active Planet-Hosting K Star
• High Dispersion Spectroscopy of Solar-type Superflare Stars. I. Temperature, Surface Gravity, Metallicity, and $v\sin i$
• Limits of ultra-high-precision optical astrometry: Stellar surface structures
• HADES RV Programme with HARPS-N at TNG: V. A super-Earth on the inner edge of the habitable zone of the nearby M-dwarf GJ 625
• Astrometric effects of solar-like magnetic activity in late-type stars and their relevance for the detection of extrasolar planets

Cited by in corpus (16)

• Stellar and substellar companions of nearby stars from Gaia DR2 - Binarity from proper motion anomaly
• The Little Engines That Could? Globular Clusters Contribute Significantly to Reionization-era Star Formation
• A Relationship Between Stellar Age and Spot Coverage
• From Starspots to Stellar Coronal Mass Ejections -- Revisiting Empirical Stellar Relations
• Stellar Properties of Active G and K Stars: Exploring the Connection Between Starspots and Chromospheric Activity
• The Stellar Variability Noise Floor for Transiting Exoplanet Photometry with PLATO
• Predictions of Astrometric Jitter for Sun-like Stars. II. Dependence on Inclination, Metallicity, and Active-Region Nesting
• How to Characterize the Atmosphere of a Transiting Exoplanet
• Closeby Habitable Exoplanet Survey (CHES). I. Astrometric Noise and Planetary Detection Efficiency due to Stellar Spots and Faculae
• Predictions of astrometric jitter for Sun-like stars. I. The model and its application to the Sun as seen from the ecliptic
• The Solar Benchmark: Rotational Modulation of the Sun Reconstructed from Archival Sunspot Records
• Multiwavelength Mitigation of Stellar Activity in Astrometric Planet Detection
• Infrared interferometry to spatially and spectrally resolve jets in X-ray binaries
• Inferring hemispheric asymmetries of stellar active regions through the information content of astrometric signals
• Astrometric exoplanet detection survives solar-like stellar contamination
• A Dataset for Exploring Stellar Activity in Astrometric Measurements from SDO Images of the Sun