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From an analysis of SNe 1972E, 1980N, 1981B, 1981D, 1983R, 1998bu, 1999cl, and 1999cp, we find that the intrinsic V-K colors of Type Ia SNe of typical luminosity (i.e., with multicolor light-curve shape (MLCS) parameter -0.4 [?] D [?] +0.2 mag) suggest a uniform color curve. V-K colors become bluer linearly with time from roughly one week before B-band maximum until one week after maximum, after which they redden linearly until four weeks after maximum. V-H colors exhibit very similar color evolution. V-J colors exhibit slightly more complex evolution, with greater scatter. The existence of V-near-infrared (NIR) color relations allows the construction of near-infrared light-curve templates that are an improvement on those of Elias et al. from 1985. We provide optical BVRI and infrared JHK photometry of the Type Ia supernovae 1999aa, 1999cl, and 1999cp. SN 1999aa is an overluminous "slow decliner" (with D = -0.47 mag). SN 1999cp is a moderately bright SN unreddened in its host. SN 1999cl is extremely reddened in its host. The V-NIR colors of SN 1999cl yield AV = 2.01 +- 0.11 mag. This leads to a distance for its host galaxy (M88) in agreement with other distance measurements for members of the Virgo Cluster.

In this paper we describe a new class of pulsating stars, the prototype of which is the bright, early, F-type dwarf ? Doradus. These stars typically have between 1 and 5 periods ranging from 0.4 to 3 days with photometric amplitudes up to 0.1 mag in Johnson V. The mechanism for these observed variations is high-order, low-degree, nonradial, gravity-mode pulsation.

Presents information on Defense Department scientists, who use special telescopes and a technology called adaptive optics, in order to capture images of spy satellites. Benefits of Star Wars to scientists; Significance of astronomers. INSETS: Stop that twinkle!.;Leave your ray bans behind..

The Carnegie Supernova Project-II (CSP-II) was an NSF-funded, four-year program to obtain optical and near-infrared observations of a "Cosmology" sample of ?100 Type Ia supernovae located in the smooth Hubble flow (0.03 ? z? 0.10). Light curves were also obtained of a "Physics" sample composed of 90 nearby Type Ia supernovae at z? 0.04 selected for near-infrared spectroscopic timeseries observations. The primary emphasis of the CSP-II is to use the combination of optical and near-infrared photometry to achieve a distance precision of better than 5%. In this paper, details of the supernova sample, the observational strategy, and the characteristics of the photometric data are provided. In a companion paper, the near-infrared spectroscopy component of the project is presented.

Relates some tales about oddball astronomers. The great pre-telescopic observer Tycho Brahe (1546-1601), who used his island observatory at Hven, Denmark, to increase the accuracy of stellar positions by a factor of ten, and his observations of Mars led to Kepler's Laws and Newton's Law of Gravity; French astronomer Guillaume Le Gentil's (1725-1792) efforts to observe the transit of Venus across the Sun; Other eccentric astronomers.