Results 31 to 40 of about 4,300 (180)
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
Multiple views of magnetism in cool stars [PDF]
, 2012 Magnetic fields are regarded as a crucial element for our understanding of stellar physics. They can be studied with a variety of methods which provide complementary - and sometimes contradictory - information about the structure, strength and dynamics ...
Arzoumanian +24 more
core +3 more sources
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
Temperature-Pressure Profile of the hot Jupiter HD 189733b from HST Sodium Observations: Detection of Upper Atmospheric Heating [PDF]
, 2012 We present transmission spectra of the hot Jupiter HD 189733b taken with the Space Telescope Imaging Spectrograph aboard HST. The spectra cover the wavelength range 5808-6380 Ang with a resolving power of R=5000. We detect absorption from the NaI doublet
Ballester, Gilda E. +6 more
core +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
Formation of starspots in self-consistent global dynamo models: Polar spots on cool stars [PDF]
, 2014 Observations of cool stars reveal dark spot-like features on their surfaces. Compared to sunspots, starspots can be bigger or cover a larger fraction of the stellar surface.
Christensen, Ulrich R. +3 more
core +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
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
Photospheric activity, rotation and magnetic interaction in LHS 6343 A [PDF]
, 2013 Context. The Kepler mission has recently discovered a brown dwarf companion transiting one member of the M4V+M5V visual binary system LHS 6343 AB with an orbital period of 12.71 days. Aims.
Herrero, E. +4 more
core +1 more source
Benchmarking pre-main sequence stellar evolutionary tracks using disk-based dynamical stellar masses
Astronomy & AstrophysicsStellar masses are a fundamental property to understand models of pre-main sequence evolution, but their values derived from Hertzsprung–Russell (HR) diagrams are strongly model dependent.
Zallio Luigi +16 more
doaj +1 more source