Using HI Nearby Galaxy Survey (THINGS) 21-cm observations of a sample of nearby (nearly face-on) galaxies we explore whether the stellar disk truncation phenomenon produces any signature either in the HI gas density and/or in the gas dynamics. Recent cosmological simulations suggest that the origin of the break on the surface brightness

B-type asteroids have a negative slope from ˜0.5 to ˜1.1 μm and beyond. What causes this? Visible to near-infrared reflectance spectra (0.4-2.5 μm) are assembled for 22 B-type asteroids. The spectra fall naturally into three groups: (1) those with negative (blue) spectral shapes like 2 Pallas (7 objects), (2) those with concave curve shapes like 24

This paper discusses some of the challenges of spectro-polarimetric observations with a large aperture solar telescope such as the ATST or the EST. The observer needs to reach a compromise between spatial and spectral resolution, time cadence, and signal-to-noise ratio, as only three of those four parameters can be pushed to the limit. Tunable

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The new generation of ground-based, large-aperture solar telescopes promises to significantly increase our capabilities to understand the many basic phenomena taking place in the Sun at all atmospheric layers and how they relate to each other. A (non-exhaustive) summary of the main scientific arguments to pursue these impressive technological goals