28,596 datasets found

We derive projected rotational velocities (vsini) for a sample of 156 Galactic OB star members of 35 clusters, HII regions, and associations. The HeI lines at 4026, 4388, and...

We present the results of a deep-imaging search for wide companions to low-mass stars and brown dwarfs using NSFCam on the Infrared Telescope Facility. We searched a sample of...

We have measured the solar phase curves in B, V, and I for 18 trans-Neptunian objects (TNOs), 7 Centaurs, and Nereid and determined the rotation curves for 10 of these targets....

This paper presents revised orbits and system masses of 14 visual double stars, in all of which at least one component is of early spectral type: WDS 00546+1911 (STT 20 AB), WDS...

We present the results of a study aimed at assessing the differences in the distribution of rotation speeds N(vsini) among young (1-15Myr) B stars spanning a range of masses...

We present a refined catalog for the positions of 179 gamma-ray burst (GRB) X-ray afterglows observed by the X-Ray Telescope (XRT) on Swift prior to 2006 November 1. The...

We present the results of a study aimed at assessing whether low and high-mass stars form similarly. Our approach is (1) to examine the observed projected rotational velocities...

The US Naval Observatory has mined over 140 astrometric catalogs, including the Astrographic Catalogue and the Two Micron All Sky Survey, for measures of double stars. This...

Our differential BV photometric observations, acquired with an automated telescope at Fairborn Observatory, show that HD 71636 is an eclipsing binary. From follow-up...

The results of 1657 speckle interferometric observations of double stars, made with the 26-inch (66cm) refractor of the US Naval Observatory, are presented. Each speckle...

We present VI photometry of the metal-poor inner halo globular clusters NGC 6293 and NGC 6541 using the WFPC2 on board the Hubble Space Telescope (HST). Our color-magnitude...

The present paper presents a tabulation of data on all 600 Galactic open clusters for which it is currently possible to calculate linear diameters. As expected, the youngest...

We present observations of intermediate-velocity clouds (IVCs) found at positive velocities in the Canadian Galactic Plane Survey Phase I region...

I use high-quality Hubble Space Telescope (HST) spectrophotometry to analyze the calibration of three popular optical photometry systems: Tycho-2 B_T_ and V_T_, Stromgren uvby,...

We present the results from the discovery and study of ~3000 chromospherically active giant and subgiant stars toward the Galactic bulge. Cone search capability for table...

In this paper we present the results of our study of period change in 547 Mira variables using data from the AAVSO (American Association of Variable Star Observers). We use...

We present a new 11.7{mu}m mosaic image of the inner Orion Nebula obtained with the T-ReCS instrument on Gemini South. The map covers 2.7'x1.6', with a diffraction-limited...

Projected rotational velocities (vsini) have been measured for 216 B0-B9 stars in the rich, dense h and {chi} Persei double cluster and compared with the distribution of...

We use new VLA Galactic plane catalogs at 5 and 1.4 GHz covering the first Galactic quadrant (350{deg}<=l<=42{deg}, |b|<=0.4{deg}) in conjunction with the MSX6C...

We present monitoring observations by the Rossi X-Ray Timing Explorer of the 2-10keV X-ray emission from the supermassive star {eta} Carinae from 1996 through late 2003. These...