Airglow in a planetary atmosphere is diagnostic of the combined effects of transport, both vertical and horizontal, and chemistry. Airglow emission on the night side in the OH(3-2, 2-1, 2-0, and 1-0), O2(c-X and a-X), and NO(C-A) bands has been reported in the past two years based on observations by VIRTIS on Venus Express [1,2,3]. Previous

The electron temperatures of high-metallicity [12 + log(O/H) > 8.2] HII regions have been studied. The empirical flux-flux relations which express the nebular-to-auroral [OIII] line ratio Q3,O (as well as the nebular-to-auroral [OII] line ratio Q2,O, and the nebular-to-auroral [NII] line ratio Q2,N) in terms of the nebular R3 and R2 line fluxes in

Active galactic nuclei (AGNs) play an important role in many aspects of modern cosmology, and of particular interest is the issue of the interplay between AGNs and their host galaxy. Using X-ray and optical data sets, we have explored the properties of a large sample of AGNs in the Subaru/XMM-Newton Deep Survey field, and studied their evolution in

Context: The dependence of amplitude on the pulsation period differs from other Cepheid-related relationships. Aims: We attempt to revise the period-amplitude (P-A) relationship of Galactic Cepheids based on multi-colour photometric and radial velocity data. Reliable P-A graphs for Galactic Cepheids constructed for the U, B, V, R_C, and IC

Comet 67P, the target of Rosetta mission, was observed in the visible and near-IR spectral regions during its perihelion approach. The observations were performed in four epochs, at heliocentric distances varying from about 3 to 1.4 AU, i. e. in the same range of the Rosetta mission. The aims of the observations were the study of the dust coma and

Context: To obtain a significant Zeeman signature in the polarised spectra of a magnetic star, we usually “add” the contributions of numerous spectral lines; the ultimate goal is to recover the spectropolarimetric prints of the magnetic field in these line additions. Aims: Here we want to clarify the meaning of these techniques of line addition; in