Context. Spectroscopic observations of the emission lines formed in the solar transition region commonly show persistent downflows on the order of 10−15 km s −1. The cause of such downflows, however, is still not fully clear and has remained a matter of debate. Aims: We aim to understand the cause of such downflows by studying the coronal and

In physically realistic, scalar-field-based dynamical dark energy models (including, e.g., quintessence), one naturally expects the scalar field to couple to the rest of the model's degrees of freedom. In particular, a coupling to the electromagnetic sector leads to a time (redshift) dependence in the fine-structure constant and a violation of the

The linear stage of hydrodynamic instability of a laminar premixed flame propagating in a Hele-Shaw cell is investigated. Our theoretical model takes into account momentum and heat losses, temperature-dependent transport coefficients, and the continuous internal structure of the flame front. The dispersion relation is obtained numerically as a

The cosmic microwave background (CMB) is a snapshot of the Universe at early times (z ∼ 1100). In the recent years, several experiments have provided constraints on the concordance ΛCDM model from a statistical analysis of the CMB anisotropies. On the other hand, many galaxy surveys will measure the 3D distribution of the dark matter component of

The binary near-Earth asteroid (65803) Didymos is the target for the Asteroid Impact and Deflection Assessment (AIDA) concept with two primary spacecraft: NASA's DART (Double Asteroid Redirection Test) impactor and ESA's Hera orbiter (Cheng et al. 2018; Michel et al. 2018). DART is NASA's first planetary defense mission and will be the first