We use statistics on the nuclear magnitudes of Jupiter Family comets to derive the number of km-sized members with perihelion distances less than 2 AU. When coupled with impact rates per comet taken from Levison et al. (2000), and with our estimate of the number of dormant comets in similar orbits yielding a dormant/active ratio of about 2, we find

The launch of the Chandra X-ray Observatory in July 1999 opened a new era in X-ray astronomy. Its unprecedented,

We study the innermost regions of bulges with surface-brightness data derived from combined HST/NICMOS and ground-based NIR profiles. Bulge profiles to 1--2 kpc may be fit with Sersic laws and show a trend with bulge-to-disk ratio: low-B/D bulges are roughly exponential, whereas higher-B/D bulges show increasing Sersic shape index, n, indicating

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We have obtained K-band spectra with CGS4 on UKIRT for circumnuclear star-forming regions in NGC 4321, NGC 2903, and NGC 7469. A comparison of the equivalent widths of Brγ emission and CO absorption with starburst models in the literature allows us to simultaneously determine the age distribution and burst decay timescales around each ring. We find

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