We analyze the stellar distribution in the Galactic disk via NIR color-magnitude diagrams (CMDs). Extinction measurements in the K band are also extracted from the diagrams both for supporting stellar counts predictions of the Besaçon and "SKY" models and for comparing with a three dimensional model of the Galactic extinction. The method is based

The STARE instrument was the first to detect the transits of an extrasolar planet in 1999. To date it has performed one of the longest running searches for transits, being in nearly continous operations since July 2001 at Teide Observatory, Tenerife. We describe the instrumental setup and the scheme that is used for data acquisition, handling and

The atmospheres of planets orbiting other stars may be studied by the technique of transit spectroscopy. This technique needs a very high SNR, so large space telescopes are needed, and bright target stars must be found. This paper uses planetary atmosphere models to discuss the SNR performance required to achieve specific science goals for both

The location of the Advanced Technology Solar Telescope (ATST) is a critical factor in the overall performance of the telescope. We have developed a set of instrumentation to measure daytime seeing, sky brightness, cloud cover, water vapor, dust levels, and weather. The instruments have been located at six sites for periods of one to two years

We present an INTEGRAL data analysis of the X-ray transient SAX J2103.5+4545 during December 2002. The source showed two type-I outbursts in this period. The INTEGRAL location agrees with the position of the recently proposed optical counterpart. A power-law model was fitted to the 10 100 keV spectrum and a photon index of 2.5±0.1 was derived. The

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