Results 21 to 30 of about 205 (134)
Doppler Imaging of Starspots [PDF]
International Astronomical Union Colloquium, 1983 ABSTRACTWe discuss a newly-developed technique for spatially resolving starspots on some of the more rapidly rotating RS CVn stars. Basically, the method uses high resolution, very high signal-to-noise spectral line profiles and exploits the Doppler velocity correspondence between position across the stellar disk and wavelength position across a ...
Steven S. Vogt, G. Donald Penrod
openaire +1 more source
Starspot Imaging Using VRI Photometry [PDF]
Symposium - International Astronomical Union, 1986 Recent progress on maximum-entropy imaging of stellar surface brightness distributions using VRI photometry and Doppler-broadened absorption line profiles is reported. VRI photometry generally provides tighter constraints on starspot configurations than does Doppler imaging (which requires the use of large telescopes).
openaire +1 more source
The STELLA Robotic Observatory on Tenerife
Advances in Astronomy, Volume 2010, Issue 1, 2010., 2010 The Astrophysical Institute Potsdam (AIP) and the Instituto de Astrofísica de Canarias (IAC) inaugurated the robotic telescopes STELLA‐I and STELLA‐II (STELLar Activity) on Tenerife on May 18, 2006. The observatory is located on the Izaña ridge at an elevation of 2400 m near the German Vacuum Tower Telescope.
Klaus G. Strassmeier +12 more
wiley +1 more source
Overfitting Affects the Reliability of Radial Velocity Mass Estimates of the V1298 Tau Planets
The Astronomical Journal, 2023 Mass, radius, and age measurements of young (≲100 Myr) planets have the power to shape our understanding of planet formation. However, young stars tend to be extremely variable in both photometry and radial velocity (RV) measurements, which makes ...
Sarah Blunt +25 more
doaj +1 more source
The Astrophysical Journal Letters, 2023 Planets orbiting M-dwarf stars are prime targets in the search for rocky exoplanet atmospheres. The small size of M dwarfs renders their planets exceptional targets for transmission spectroscopy, facilitating atmospheric characterization.
Sarah E. Moran +23 more
doaj +1 more source
Asteroseismic Signature of a Large Active Region
Frontiers in Astronomy and Space Sciences, 2019 Axisymmetric magnetic activity on the Sun and sun-like stars increases the frequencies of the modes of acoustic oscillation. However, it is unclear how a corotating patch of activity affects the oscillations, since such a perturbation is unsteady in the ...
Emanuele Papini +2 more
doaj +1 more source
Measuring the Temperature of Starspots from Multi-filter Photometry
The Astronomical Journal, 2023 Using simultaneous multi-filter observations during the transit of an exoplanet around a K dwarf star, we determine the temperature of a starspot through modeling the radius and position with wavelength-dependent spot contrasts.
Maria C. Schutte +7 more
doaj +1 more source
Starspot photometry with robotic telescopes [PDF]
Astronomy and Astrophysics Supplement Series, 1997 We report on the progress of our ongoing photometric monitoring program of spotted late-type stars with automatic photoelectric telescopes (APTs) on Mt. Hopkins in Arizona and on Mt. Etna in Sicily. We present 9 250 differential UBV and/or observations for altogether 23 chromospherically active stars, singles and binaries, pre main sequence and post ...
K. G. Strassmeier +3 more
openaire +1 more source
Mapping Stellar Surfaces. II. An Interpretable Gaussian Process Model for Light Curves
The Astronomical Journal, 2021 The use of Gaussian processes (GPs) as models for astronomical time series data sets has recently become almost ubiquitous, given their ease of use and flexibility.
Rodrigo Luger +2 more
doaj +1 more source
The Astrophysical Journal, 2023 Measuring the coverage of dark spots on cool stars is important to understanding how stellar magnetic activity scales with the rotation rate and convection zone depth. In this respect, it is crucial to infer surface magnetic patterns on G and K stars, to
Engin Bahar +6 more
doaj +1 more source