In this study, we look specifically at binary white dwarfs where the companion is a main sequence star. In particular, we look at very hot white dwarfs, many of which demonstrate the "hydrogen problem" in which modeling of their hydrogen absorption features, and optical features in general, do not appear to give accurate temperatures. The two

The MANCHA3D code is a versatile tool for numerical simulations of magnetohydrodynamic (MHD) processes in solar/stellar atmospheres. The code includes nonideal physics derived from plasma partial ionization, a realistic equation of state and radiative transfer, which allows performing high-quality realistic simulations of magnetoconvection, as well

We present JWST images of the well-known planetary nebula NGC 6720 (the Ring Nebula), covering wavelengths from 1.6 to 25 $\, \mu$m. The bright shell is strongly fragmented with some 20 000 dense globules, bright in H 2, with a characteristic diameter of 0.2 arcsec and density n H ~ 10 5-10 6 cm -3. The shell contains a narrow ring of polycyclic

We present a comprehensive analysis of the Hubble Space Telescope observations of the atmosphere of WASP-121 b, an ultra-hot Jupiter. After reducing the transit, eclipse, and phase-curve observations with a uniform methodology and addressing the biases from instrument systematics, sophisticated atmospheric retrievals are used to extract robust

Hasta ahora, la única formar de monitorizar de manera consistente el hemisferio del Sol no visible (farside de aquí en adelante) desde la Tierra es el uso de métodos heliosísmicos. Estos métodos interpretan las oscilaciones del hemisferio visible (nearside de aquí en adelante) para inferir la actividad del farside, que es de gran importancia en las

Fullerenes have been observed in several astronomical objects since the discovery of C 60 in the mid-infrared (mid-IR) spectrum of the planetary nebula (PN) Tc 1. It has been suggested that the carriers of the broad unidentified infrared (UIR) plateau features, such as the 9-13 μm emission feature (12 μm hereafter), may be related to the formation