We measured phase velocities at 13 periods from 20 s to 143 s using Rayleigh wave data recorded at recently installed, dense (135) broadband seismic stations in the Arabian shield and determined the shear‐wave velocity structure. Our results clearly reveal a 300 km wide upper mantle seismic low‐velocity zone (LVZ) beneath the western Arabian shield at a depth of 60 km and with a thickness of 130 km. The LVZ has a north‐south trend and follows the late‐Cenozoic volcanic areas. The lithosphere beneath the western Arabian shield is remarkably thin (60–90 km). The 130 km thick mantle LVZ does not appear beneath the western Red Sea and the spreading axis. Thus, the Red Sea at 20°–26°N is an asymmetric rift, with thin lithosphere located east of the Red Sea axis, as predicted by the low‐angle detachment model for rift development. Passive rifting at the Red Sea and extensional stresses in the shield are probably driven by slab pull from the Zagros subduction zone. The low shear‐wave velocity (4.0–4.2 km/s) and the geometry of LVZ beneath the western shield indicate northward flow of hot asthenosphere from the Afar hot spot. The upwelling of basaltic melt in fractures or zones of localized lithospheric thinning has produced extensive late Cenozoic volcanism on the western edge of the shield, and the buoyant LVZ has caused pronounced topography uplift there. Thus, the evolution of the Red Sea and the Arabian shield is driven by subduction of the Arabian plate along its northeastern boundary.

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We observed the post-common-envelope eclipsing binary with a white dwarf component, QS Vir, using the 1.88 m telescope of Kotammia Observatory in Egypt. The new observations were analyzed together with all multicolor light curves available online (sampling a period of 25 years), using a full-feature binary system modeling software based on Roche geometry. This is the first time complete photometric modeling was done with most of these data. QS Vir is a detached system, with the red dwarf component underfilling its Roche lobe by a small margin. All light curves feature out-of-eclipse variability that is associated with ellipsoidal variation, mutual irradiation and irregularities in surface brightness of the tidally distorted and magnetically active red dwarf. We tested models with one, two and three dark spots and found that one spot is sufficient to account for the light curve asymmetry in all datasets, although this does not rule out the presence of multiple spots. We also found that a single spotted model cannot fit light curves observed simultaneously in different filters. Instead, each filter requires a different spot configuration. To thoroughly explore the parameter space of spot locations, we devised a grid-search procedure and used it to find consistent solutions. Based on this, we conclude that the dark spot responsible for light curve distortions has been stable for the past 15 years, after a major migration that happened between 1993 and 2002, possibly due to a flip-flop event.