We survey 223 916 auroral records from the Northern hemisphere observed between 1650 January and 2024 July, making full allowance for the secular change in the geomagnetic field. We generate criteria for defining extreme auroral events that are met on 0.015 per cent and 0.023 per cent of nights since 1650 and 1790, respectively. After discussing

Episodic accretion is a fundamental process in the build-up of the stellar mass. EX Lupi-type eruptive young stars (EXors) represent one of the main types of episodic accretion. We study the recently discovered EXor Gaia23bab during its 2023 outburst. We obtained optical and near-infrared photometry and spectroscopy to probe the variation of the

We report the discovery and confirmation of TOI-4465 b, a 1.25R J ‑ 0.07 R J + 0.08 R J , 5.89M J ± 0.26M J giant planet orbiting a G dwarf star at d ≃ 122 pc. The planet was detected as a single-transit event in data from Sector 40 of the Transiting Exoplanet Survey Satellite (TESS) mission. Radial velocity (RV) observations of TOI-4465 showed a

We report JWST NIRSpec/G395H observations of TOI-1685 b, a hot rocky super-Earth orbiting an M2.5V star, during a full orbit. We obtain transmission and emission spectra of the planet and characterize the properties of the phase curve, including its amplitude and offset. The transmission spectrum rules out clear H 2-dominated atmospheres, while

To identify long-period variable (LPV) stars in IC 10—the nearest starburst galaxy of the Local Group—we conducted an optical monitoring survey using the 2.5 m Isaac Newton Telescope with the wide-field camera (WFC) in the i band and V band from 2015 to 2017. We created a photometric catalog for 53,579 stars within the area of CCD4 of WFC (∼0.07

In our previous paper, we employed the Landau collisional operator together with the moment method of Grad and considered various generalizations of the Braginskii model, such as a multifluid formulation of the 21- and 22-moment models valid for general masses and temperatures, where all of the considered moments are described by their evolution