Search Publications
Layered mound, inverted channels and polygonal fractures from the Makgadikgadi pan (Botswana): Possible analogues for Martian aqueous morphologies
Franchi, Fulvio; MacKay, Ruaraidh; Selepeng, Ame Thato +1 more
Layered mounds and inverted channels with polygonal fractures from the Ntwetwe Pan in the Makgadikgadi Basin (central Botswana) have been herein investigated. These morphologies are from an evaporitic basin (the Makgadikgadi Basin) that is the remnant of an ancient Pleistocene lake and is currently part of the world's largest evaporitic system.
Secular Extragalactic Parallax: Measurement Methods and Predictions for Gaia
Darling, Jeremy; Paine, Jennie; Graziani, Romain +1 more
Secular extragalactic parallax caused by the solar system's velocity relative to the cosmic microwave background rest frame may be observable as a dipole proper motion field with amplitude 78 µas yr-1 Mpc. Nearby galaxies also exhibit proper motions caused by their transverse peculiar velocities that prevent detection of secular p…
First stars that could significantly perturb comet motion are finally found
Dybczyński, Piotr A.; Królikowska, Małgorzata; Wysoczańska, Rita
Since 1950 when Oort published his paper on the structure of the cloud of comets it is believed that stars passing near this hypothetical cometary reservoir play an important role in the dynamical evolution of long-period comets and injecting them into the observability region of the Solar system. The aim of this paper is to discuss two cases in w…
Saturn atmospheric dynamics one year after Cassini: Long-lived features and time variations in the drift of the Hexagon
Hueso, R.; Sánchez-Lavega, A.; Rojas, J. F. +15 more
We examine Saturn's atmospheric dynamics with observations in the visible range from ground-based telescopes and Hubble Space Telescope (HST). We present a detailed analysis of observations acquired during 2018 obtaining drift rates of major meteorological systems from the equator to the north polar hexagon. A system of polar storms that appeared …
Photometric study of the young open clusters IC 1442, King 21, and Trumpler 7
Joshi, Y. C.; Maurya, Jayanand; Gour, A. S.
We carried out the UBVRcIc photometric study of three poorly studied young open clusters IC 1442, King 21, and Trumpler 7 (Tr 7). We obtained 263, 244, and 128 member stars using Gaia Data Release 2 proper motions and parallaxes in IC 1442, King 21, and Tr 7, respectively. The reddening, E(B - V), was derived to be 0.54 ± 0.0…
A precise benchmark for cluster scaling relations: Fundamental Plane, Mass Plane, and IMF in the Coma cluster from dynamical models
Krajnović, Davor; Kobayashi, Chiaki; Cappellari, Michele +4 more
We study a sample of 148 early-type galaxies in the Coma cluster using SDSS photometry and spectra, and calibrate our results using detailed dynamical models for a subset of these galaxies, to create a precise benchmark for dynamical scaling relations in high-density environments. For these galaxies, we successfully measured global galaxy properti…
Study of the Decay Rates of the Umbral Area of Sunspot Groups Using a High-resolution Database
Muraközy, Judit
The emergence and decay of the sunspot groups are important components of the solar dynamo models. There are two different types of studies on the evolution of active regions. One of them is based on fewer data with higher spatial resolution, the other one uses more data with lower spatial resolution. The input data of the present study allow the …
The Space Environment and Atmospheric Joule Heating of the Habitable Zone Exoplanet TOI 700 d
Drake, Jeremy J.; Garraffo, C.; Alvarado-Gómez, J. D. +4 more
We investigate the space environment conditions near the Earth-size planet TOI 700 d using a set of numerical models for the stellar corona and wind, the planetary magnetosphere, and the planetary ionosphere. We drive our simulations using a scaled-down stellar input and a scaled-up solar input in order to obtain two independent solutions. We find…
New constraints on the HR 8799 planetary system from mid-infrared direct imaging
Fedele, D.; Kissler-Patig, M.; van den Ancker, M. E. +2 more
Direct imaging is a tried and tested method of detecting exoplanets in the near-infrared (IR), but has so far not been extended to longer wavelengths. New data at mid-IR wavelengths (8-20 µm) can provide additional constraints on planetary atmospheric models. We use the VLT Imager and Spectrometer for the mid-IR (VISIR) instrument on the VLT…
OGLE-2018-BLG-1269Lb: A Jovian Planet with a Bright I = 16 Host
Han, Cheongho; Udalski, Andrzej; Lee, Chung-Uk +57 more
We report the discovery of a planet in the microlensing event OGLE-2018-BLG-1269 with a planet-host mass ratio q ∼ 6 × 10-4, i.e., 0.6 times smaller than the Jupiter/Sun mass ratio. Combined with the Gaia parallax and proper motion, a strong one-dimensional constraint on the microlens parallax vector allows us to significantly reduce th…