We present an extragalactic perspective of an extended stellar tidal stream wrapping around the edge-on spiral galaxy NGC 5907. Our deep images reveal for the first time a large-scale complex of arcing loops that is an excellent example of how low-mass satellite accretion can produce an interwoven, rosette-like structure of debris dispersed in the

Using data from observing seasons 1977 through 1984, an analysis of the low l, high n p-mode solar spectra is made with a 0.9 μHz resolution. Frequencies and amplitudes of modes of l 3 and 11 n 33 are determined for each observing season. No clear variation of the frequencies at the 1 μHz level is found and the amplitudes remain constant to ˜ 20

The Global Oscillation Network Group (GONG) project is planning to place six observing stations around the world to observe the solar oscillations as continuously as possible. This paper describes the procedures that are being used to select the six sites. The latest results of measurements of cloud cover obtained by networks of 6 (out of 10)

We have determined the gravitational torque of a sample of 45 galaxies observed at K band with the 4.2m William Herschel Telescope. The results of this sample, combined with those for a sample of 30 galaxies previously analysed (Buta & Block 2001), show that the gravitational bar torque correlates only weakly with the optical bar type listed in the

The 1.5-meter GREGOR solar telescope is a new facility for high-resolution observations of the Sun. The telescope is located at the Spanish Observatorio del Teide on Tenerife. The telescope incorporates advanced designs for a foldable-tent dome, an open steel-truss telescope structure, and active and passive means to minimize telescope and mirror

We present the GTC data processing subsystem, hereinafter ``Data Factory''. The main objectives, functionality and overall philosophy are described. We also briefly outlay the architectural description of the Data Factory and its organization. The current state of development is also presented as well as some real reduction examples.