We present observational evidence, from Hαin face-on galaxies, which strongly favours the hypothesis that escaping photons from H II regions are the basic cause of the ionization of the diffuse ionized gas in galaxy discs, and by implication are the chief cause of the Reynolds layer in the Milky Way, and refer the reader to models based on these

We present ARC2 (Astrophysically Robust Correction 2), an open-source python-based systematics-correction pipeline, to correct for the Kepler prime mission long-cadence light curves. The ARC2 pipeline identifies and corrects any isolated discontinuities in the light curves and then removes trends common to many light curves. These trends are

We present Roche tomograms of the K4V secondary star in the cataclysmic variable AE Aqr, reconstructed from two data sets taken 9 d apart, and measure the differential rotation of the stellar surface. The tomograms show many large, cool starspots, including a large high-latitude spot and a prominent appendage down the trailing hemisphere. We find

Trans-Neptunian objects (TNOs) are considered some of the most pristine objects in the Solar System. Their surfaces display a wide range of compositions, going from surfaces covered by dark irradiation mantels, to surfaces totally covered by ices. According to models of the retention of volatiles, only TNOs with a diameter d &gt 1000 km are

Last year (Campins et al. 2006), we reported near-infrared rotational variability in ground-based spectra of comet-asteroid transition object 944 Hidalgo. Since then, we carried out a rotationally resolved study of Hidalgo at mid-infrared wavelengths using the Infrared Spectrograph (IRS) on NASA's Spitzer Space Telescope. We obtained 7 to 38 micron

We report the new spectroscopic observations of the gravitational lens RXJ 021+4529 with the multi-mode focal reducer SCORPIO of the SAO RAS 6 m telescope. The new spectral observations were compared with the previously observed spectra of components A and B of RXJ 0921+4529, i.e., the same components observed in different epochs. We found a