Search Publications
Turbulence and wave transmission at an ICME-driven shock observed by the Solar Orbiter and Wind
Kilpua, E. K. J.; Horbury, T. S.; O'Brien, H. +10 more
Aims: An interplanetary coronal mass ejection (ICME) event was observed by the Solar Orbiter at 0.8 AU on 2020 April 19 and by Wind at 1 AU on 2020 April 20. Futhermore, an interplanetary shock wave was driven in front of the ICME. Here, we focus on the transmission of the magnetic fluctuations across the shock and we analyze the characterist…
Indications for very high metallicity and absence of methane in the eccentric exo-Saturn WASP-117b
Henning, Thomas; Jordán, Andrés; Apai, Dániel +12 more
Aims: We investigate the atmospheric composition of the long-period (Porb = 10 days) eccentric exo-Saturn WASP-117b. WASP-117b could be similar in atmospheric temperature and chemistry to WASP-107b. In mass and radius, WASP-117b is similar to WASP-39b, which allows a comparative study of these planets.
Methods: We analyzed a n…
Optimising and comparing source-extraction tools using objective segmentation quality criteria
Venhola, Aku; Peletier, Reynier; Chamba, Nushkia +4 more
Context. With the growth of the scale, depth, and resolution of astronomical imaging surveys, there is increased need for highly accurate automated detection and extraction of astronomical sources from images. This also means there is a need for objective quality criteria, and automated methods to optimise parameter settings for these software too…
A bright inner disk and structures in the transition disk around the very low-mass star CIDA 1
Testi, L.; Tazzari, M.; Natta, A. +7 more
The frequency of Earth-sized planets in habitable zones appears to be higher around M-dwarfs, making these systems exciting laboratories to investigate planet formation. Observations of protoplanetary disks around very low-mass stars and brown dwarfs remain challenging and little is known about their properties. The disk around CIDA 1 (~0.1-0.2 M<…
TOI-269 b: an eccentric sub-Neptune transiting a M2 dwarf revisited with ExTrA
Bouchy, F.; de Medeiros, J. R.; Helled, R. +59 more
We present the confirmation of a new sub-Neptune close to the transition between super-Earths and sub-Neptunes transiting the M2 dwarf TOI-269 (TIC 220 479 565, V = 14.4 mag, J = 10.9 mag, R⋆ = 0.40 R⊙, M⋆ = 0.39 M⊙, d = 57 pc). The exoplanet candidate has been identified in multiple TESS sectors, and va…
Forbidden hugs in pandemic times. I. Luminous red nova AT 2019zhd, a new merger in M 31
Lundqvist, P.; Rest, A.; Munari, U. +20 more
We present the follow-up campaign of the luminous red nova (LRN)
Asteroid absolute magnitudes and phase curve parameters from Gaia photometry
Cellino, A.; Muinonen, K.; Penttilä, A. +2 more
Aims: We perform light curve inversion for 491 asteroids to retrieve phase curve parameters, rotation periods, pole longitudes and latitudes, and convex and triaxial ellipsoid shapes by using the sparse photometric observations from Gaia Data Release 2 and the dense ground-based observations from the DAMIT database. We develop a method for th…
Bird's eye view of molecular clouds in the Milky Way. I. Column density and star formation from sub-parsec to kiloparsec scales
Kainulainen, Jouni; Spilker, Andri; Orkisz, Jan
Context. Describing how the properties of the interstellar medium are combined across various size scales is crucial for understanding star formation scaling laws and connecting Galactic and extragalactic data of molecular clouds.
Aims: We describe how the statistical structure of the clouds and its connection to star formation changes from s…
First Solar Orbiter observation of the Alfvénic slow wind and identification of its solar source
André, N.; Fedorov, A.; Livi, S. +27 more
Context. Turbulence dominated by large-amplitude, nonlinear Alfvén-like fluctuations mainly propagating away from the Sun is ubiquitous in high-speed solar wind streams. Recent studies have demontrated that slow wind streams may also show strong Alfvénic signatures, especially in the inner heliosphere.
Aims: The present study focuses on the c…
Detectability of biosignatures on LHS 1140 b
Rauer, Heike; Sousa-Silva, Clara; Wunderlich, Fabian +4 more
Context. Terrestrial extrasolar planets around low-mass stars are prime targets when searching for atmospheric biosignatures with current and near-future telescopes. The habitable-zone super-Earth LHS 1140 b could hold a hydrogen-dominated atmosphere, and is an excellent candidate for detecting atmospheric features.
Aims: In this study we inv…