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Infrared surface brightness technique applied to RR Lyrae stars from the solar neighborhood
DOI: 10.1051/0004-6361/202449850 Bibcode: 2024A&A...690A.295Z

Gieren, Wolfgang; Pietrzyński, Grzegorz; Haas, Martin +9 more

Context. The Baade-Wesselink (BW) method, also known as the pulsation parallax method, allows us to estimate distances to individual pulsating stars. Accurate geometric parallaxes obtained by the Gaia mission serve us in the calibration of the method and in the determination of its precision. This method also provides a way of determining mean rad…

2024 Astronomy and Astrophysics
Gaia 2
First comparative exoplanetology within a transiting multi-planet system: Comparing the atmospheres of V1298 Tau b and c
DOI: 10.1051/0004-6361/202451127 Bibcode: 2024A&A...692A.198B

Fortney, Jonathan J.; Désert, Jean-Michel; Line, Michael R. +13 more

The V1298 Tau system is a multi-planet system that provides the opportunity to perform comparative exoplanetology between planets orbiting the same star. Because of its young age (20–30 Myr), this system also provides the opportunity to compare the planet's early evolutionary properties, right after their formation. We present the first atmospheri…

2024 Astronomy and Astrophysics
eHST 2
On the Determining Physical Factor of Jet-related Coronal Mass Ejections' Morphology in the High Corona
DOI: 10.3847/1538-4357/ad445c Bibcode: 2024ApJ...968..110D

Shen, Yuandeng; Duan, Yadan; Tang, Zehao +2 more

A solar jet can often cause coronal mass ejections (CMEs) with different morphologies in the high corona, for example, jet-like CMEs, bubble-like CMEs, and so-called twin CMEs that include a pair of simultaneous jet-like and bubble-like CMEs. However, what determines the morphology of a jet-related CME is still an open question. Using high spatiot…

2024 The Astrophysical Journal
SOHO 2
Confirmation of a Sub-Saturn-size Transiting Exoplanet Orbiting a G Dwarf: TOI-1194 b and a Very Low Mass Companion Star: TOI-1251 B from TESS
DOI: 10.1088/1674-4527/ad057b Bibcode: 2024RAA....24c5012W

Zheng, Jie; Bieryla, Allyson; Howell, Steve B. +18 more

We report the confirmation of a sub-Saturn-size exoplanet, TOI-1194 b, with a mass of about M J, and a very low mass companion star with a mass of about 96.5 ± 1.5 M J, TOI-1251 B. Exoplanet candidates provided by the Transiting Exoplanet Survey Satellite (TESS) are suitable for further foll…

2024 Research in Astronomy and Astrophysics
Gaia 2
One-dimensional Microphysics Model of Venusian Clouds from 40 to 100 km: Impact of the Middle-atmosphere Eddy Transport and SOIR Temperature Profile on the Cloud Structure
DOI: 10.3847/PSJ/ad25f3 Bibcode: 2024PSJ.....5...57K

Vandaele, Ann Carine; Terada, Naoki; Imamura, Takeshi +4 more

We conducted a simulation of H2SO4 vapor, H2O vapor, and H2SO4–H2O liquid aerosols from 40 to 100 km, using a 1D Venus cloud microphysics model based on the one detailed in Imamura & Hashimoto. The cloud distribution obtained is in good agreement with in situ observations by Pio…

2024 The Planetary Science Journal
VenusExpress 2
Machine learning applications in studies of the physical properties of active galactic nuclei based on photometric observations
DOI: 10.1051/0004-6361/202346557 Bibcode: 2024A&A...685A.107M

Ackermann, Markus; Kowalski, Marek; Mechbal, Sarah

Context. We investigate the physical nature of active galactic nuclei (AGNs) using machine learning (ML) tools.
Aims: We show that the redshift, z, bolometric luminosity, LBol, central mass of the supermassive black hole (SMBH), MBH, Eddington ratio, λEdd, and AGN class (obscured or unobscured) can be reconstr…

2024 Astronomy and Astrophysics
Gaia 2
Ejection and dynamics of aggregates in the coma of comet 67P/Churyumov-Gerasimenko
DOI: 10.1051/0004-6361/202348692 Bibcode: 2024A&A...687A.289L

Agarwal, J.; Lemos, P.; Marschall, R. +1 more

Context. The process of gas-driven ejection of refractory materials from cometary surfaces continues to pose a challenging question in cometary science. The activity modeling of comet 67P/Churyumov-Gerasimenko, based on data from the Rosetta mission, has significantly enhanced our comprehension of cometary activity. But thermophysical models have …

2024 Astronomy and Astrophysics
Rosetta 2
Characterization of aqueous alteration and formation of salty exposures at Ius Chasma, Mars
DOI: 10.1016/j.icarus.2023.115800 Bibcode: 2024Icar..40815800W

Flahaut, Jessica; Weitz, Catherine M.; Bishop, Janice L. +6 more

Intriguing outcrops in Ius Chasma provide a window into past aqueous processes in Valles Marineris, Mars. Hydrous sulfate minerals are abundant throughout this region, but one area in Ius Chasma includes phyllosilicates, opal, and additional materials with unusual spectral features. This study at Geryon Montes, an east-west horst that divides Ius …

2024 Icarus
MEx 2
Variation in the Pedersen Conductance Near Jupiter's Main Emission Aurora: Comparison of Hubble Space Telescope and Galileo Measurements
DOI: 10.1029/2023JA032122 Bibcode: 2024JGRA..12932122R

Nichols, J. D.; Vogt, M. F.; Rutala, M. J. +1 more

We present the first large-scale statistical survey of the Jovian main emission (ME) to map auroral properties from their ionospheric locations out into the equatorial plane of the magnetosphere, where they are compared directly to in-situ spacecraft measurements. We use magnetosphere-ionosphere (MI) coupling theory to calculate currents from the …

2024 Journal of Geophysical Research (Space Physics)
Ulysses eHST 2
Does High-Latitude Ionospheric Electrodynamics Exhibit Hemispheric Mirror Symmetry?
DOI: 10.5194/angeo-42-229-2024 Bibcode: 2024AnGeo..42..229H

Hatch, Spencer Mark; Vanhamäki, Heikki; Magnus Laundal, Karl +6 more

Ionospheric electrodynamics is a problem of mechanical stress balance mediated by electromagnetic forces. Joule heating (the total rate of frictional heating of thermospheric gases and ionospheric plasma) and ionospheric Hall and Pedersen conductances comprise three of the most basic descriptors of this problem. More than half a century after iden…

2024 Annales Geophysicae
Cluster 2