Search Publications
CCD Positions for the Outer Planets in 1996-1997 Determined in the Extragalactic Reference Frame
Stone, Ronald C.
This paper presents 316 new equatorial positions for the planets Uranus, Neptune, and Pluto obtained in 1996-1997 with the Flagstaff Astrometric Scanning Transit Telescope (FASTT). All the positions were determined in the extragalactic reference frame using CCD observations and are accurate to ~+/-0.2" in each coordinate. When these positions are …
Hubble Space Telescope Resolved Image and Spectra of the Z ~= 2 QSO 1345+584
Hutchings, J. B.
QSO 1345+584 has been spatially resolved by direct images and in spectral images, and has asymmetrically extended flux to the west, where its inner radio structure is seen. The brightest knots in the resolved flux correspond closely with knots in the curved radio jet, and the brightest knot has a velocity of approach of some 3000 km s^-1 with resp…
The Red Horizontal-Branch Star HD 17072
Lee, Jae-Woo; Carney, Bruce W.; Habgood, Michael J.
We summarize the results of a spectroscopic analysis of HD 17072, finding it to be a metal-poor ([Fe/H] = -1.17) red horizontal-branch star with T_eff = 5375 K and log g = 2.4. We also derive a radial velocity of 62.8 km s^-1. It has the best determined Hipparcos trigonometric parallax among the metal-poor field horizontal-branch stars and support…
Omega, Age, and H_0 Implications of Recent Hubble Space Telescope Data in the Coma Cluster
Baum, William A.
This paper presents a way of finding mutually consistent values of Omega_M, t_0, and H_0. This approach is illustrated using recent Coma Cluster distance data, together with recent Hipparcos data for RR Lyrae stars. The age of the universe is derived by two completely independent methods, both linked to the RR Lyrae stars. The two methods can be m…
Hubble Space Telescope Spectra of 3C 279: A Lyman Limit System at Low Redshift
Stocke, John T.; Blades, J. Chris; Penton, Steve +2 more
We present Hubble Space Telescope (HST) Faint Object Spectrograph spectra of the blazar 3C 279 obtained during two recent optical outbursts of this source, maximizing the sensitivity to weak foreground absorption systems at far-UV wavelengths for this sight line. Eighteen absorption systems were detected above an observed 3 sigma limiting equivale…
Parallaxes and Proper Motions of Prototypes of Astrophysically Interesting Classes of Stars
Kundu, Arunav; Trimble, Virginia
Hipparcos data are presented for 13 stars belonging to six different evolutionary types that present various puzzles. There are three FK Comae stars, one Wolf-Rayet binary, the ``galloping giant'' FG Sagittae, two high-velocity B stars, two runaway T Tauri stars, and four cataclysmic variables. Most of the numbers are of limited statistical signif…