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The HR 1614 Group and HIPPARCOS Astrometry
Eggen, Olin J.
The evidence for the existence of the important HR 1614 supercluster and group of rare rich CN stars is examined with the use of Hipparcos astrometry. Group membership is supported by Hipparcos parallaxes except for two stars for which available evidence suggests uncertainty in the Hipparcos values.
Hubble Space Telescope Wide Field Planetary Camera 2 Imaging of UGC 12695: A Remarkably Unevolved Galaxy at Low Redshift
Impey, C. D.; Bothun, G. D.; O'Neil, Karen +1 more
Utilizing the F814W and F300W filters, short-exposure Hubble Space Telescope Wide Field Planetary Camera 2 images were taken of UGC 12695, a nearby (z ~ 0.021) low surface brightness disk galaxy. UGC 12695 has an unusual morphology, consisting of a Y-shaped nucleus surrounded by a faint spiral arm with a number of bright H ii regions interspersed …
The Sirius Supercluster and Missing Mass near the Sun
Eggen, Olin J.
The Hipparcos results confirm some 50 members of the Sirius supercluster in the Bright Star Catalogue. The resulting, well-defined color-luminosity array indicates an age of 4 x 10^8 yr from conventional (no overshoot) models. A comparison of the luminosity function obtained from members in the Bright Star Catalogue, unbiased as to proper motion, …
Hubble Space Telescope Astrometric Observations and Orbital Mean Motion Corrections for the Inner Uranian Satellites
Pascu, Dan; Rohde, James R.; Seidelmann, P. Kenneth +6 more
The 10 small inner satellites of Uranus were discovered in 1986 with Voyager 2 and not seen again until 1994, when eight were recovered with the Hubble Space Telescope Wide Field Planetary Camera 2 for astrometric, dynamical, and photometric studies. Thirty-three exposures were taken on 1994 August 14 with the PC1 chip in the BVRI filters. Measura…
Extreme Ultraviolet Explorer Investigation of Three Short-Period Binary Stars
Rucinski, Slavek M.
Extreme Ultraviolet Explorer spectroscopic observations (SW, MW, and LW bands, covering 80-160, 170-350, and 300-450 Å with resolutions 0.5, 1, and 2 Å, respectively) and photometric observations (Deep Sky Survey [DSS], broadband 70-140 Å) have been obtained for two contact binaries, 44i Boo B and VW Cep, and one close but detached binary, ER Vul.…
New Optical Fields and Candidates of 10 3C Radio Sources. I. The R-Band Images
Baum, Stefi A.; McCarthy, Patrick J.; Sparks, William B. +6 more
Using new R-band images acquired as part of the 3CR Snapshot Survey with the Wide Field Planetary Camera 2 on the Hubble Space Telescope, we present positive optical identifications of three previously unidentified 3C radio sources (3C 91, 134, and 141). The fields of five others (3C 131, 152, 399.1, 415.2, and 468.1) are also presented with tenta…
Interstellar Absorption Lines in the Spectrum of the Starburst Galaxy NGC 1705
Sahu, M. S.
A Goddard High Resolution Spectrograph archival study of the interstellar absorption lines in the line of sight to the H i-rich, starburst dwarf galaxy NGC 1705 in the 1170 to 1740 Å range at ~120 km s^-1 resolution is presented. The absorption features arising because of photospheric lines are distinctly different from the interstellar lines: the…
Correlation of the HIPPARCOS and Allegheny Observatory Parallax Catalogs
Gatewood, George; Kiewiet de Jonge, Joost; Persinger, Timothy
No significant difference is found between the systems of the Hipparcos and Allegheny Observatory MAP parallax catalogs. The correlation of the parallaxes of 63 stars common to both programs is 0.9995 +/- 0.0001, with an average standard deviation of the difference of 0.0023". While there is no indication of systematic difference in the two progra…
Spatially Resolved Spectra of 3C Galaxy Nuclei
Nelson, C.; Hutchings, J. B.; Kaiser, M. E. +3 more
We present and discuss visible-wavelength long-slit spectra of four low-redshift 3C galaxies obtained with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope (HST). The slit was aligned with near-nuclear jetlike structure seen in HST images of the galaxies, to give unprecedented spatial resolution of their inner regions. In 3C …
A Possible Companion to Proxima Centauri
Benedict, G. F.; Franz, O. G.; Bruhweiler, F. C. +10 more
We report Hubble Space Telescope observations that provide evidence for a companion to Proxima Centauri (Gl 551), the closest star to the Sun. Data acquired with the Faint Object Spectrograph (FOS), used as a coronagraphic camera, show excess light that can be interpreted as being from a substellar object within 0.5" of Proxima Cen. Two observatio…