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Hubble Space Telescope Imaging of the CFRS and LDSS Redshift Surveys. I. Morphological Properties
DOI: 10.1086/305621 Bibcode: 1998ApJ...499..112B

Tresse, Laurence; Brinchmann, Jarle; Broadhurst, Tom +9 more

We analyze Hubble Space Telescope images of a complete sample of 341 galaxies drawn from the CFRS and LDSS ground-based redshift surveys. In this, the first paper in the series, each galaxy has been morphologically classified according to a scheme similar to that developed for the Medium Deep Survey. We discuss the reproducibility of these classif…

1998 The Astrophysical Journal
eHST 235
The Far-Ultraviolet Oxygen Airglow of Europa and Ganymede
DOI: 10.1086/305604 Bibcode: 1998ApJ...499..475H

Feldman, P. D.; Strobel, D. F.; McGrath, M. A. +1 more

Far-UV spectra of Europa and Ganymede, acquired by the Hubble Space Telescope Goddard High Resolution Spectrograph, indicate that, in addition to faintly reflected sunlight, both satellites emit O I 1304 Å and O I 1356 Å airglow radiation. The observed brightnesses of the reflected solar C II 1335 Å feature indicate that the disk-averaged albedos …

1998 The Astrophysical Journal
eHST 234
The Optical Properties of Gravitational Lens Galaxies as a Probe of Galaxy Structure and Evolution
DOI: 10.1086/306502 Bibcode: 1998ApJ...509..561K

Keeton, C. R.; Kochanek, C. S.; Falco, E. E.

We combine photometry and lens modeling to study the properties of 17 gravitational lens galaxies between z = 0.1 and ~1. Most of the lens galaxies are passively evolving early-type galaxies, with a few spirals. The colors, scale lengths, and ellipticities of lens galaxies are similar to those of the general population of early-type galaxies, alth…

1998 The Astrophysical Journal
eHST 229
Ulysses' return to the slow solar wind
DOI: 10.1029/97GL03444 Bibcode: 1998GeoRL..25....1M

Forsyth, R.; Balogh, A.; McComas, D. J. +9 more

After ten long years of wandering the uncharted seas, Ulysses returned to his home port of Ithaca. Similarly, after its unprecedented five year odyssey through the previously uncharted regions over the poles of the Sun, the Ulysses spacecraft has returned to the slow, variable solar wind which dominates observations near the ecliptic plane. Solar …

1998 Geophysical Research Letters
Ulysses 228
The Problem of HIPPARCOS Distances to Open Clusters. I. Constraints from Multicolor Main-Sequence Fitting
DOI: 10.1086/306077 Bibcode: 1998ApJ...504..170P

Pinsonneault, Marc H.; Stauffer, John; Soderblom, David R. +2 more

Parallax data from the Hipparcos mission allow the direct distance to open clusters to be compared with the distance inferred from main-sequence (MS) fitting. There are surprising differences between the two distance measurements, indicating either the need for changes in the cluster compositions or reddening, underlying problems with the techniqu…

1998 The Astrophysical Journal
Hipparcos 220
Optical-Infrared Spectral Energy Distributions of Z > 2 Lyman Break Galaxies
DOI: 10.1086/300291 Bibcode: 1998AJ....115.1329S

Sawicki, Marcin; Yee, H. K. C.

Broadband optical and IR spectral energy distributions are determined for spectroscopically confirmed z > 2 Lyman break objects in the Hubble Deep Field (HDF). These photometric data are compared with spectral synthesis models which take into account the effects of metallicity and of internal reddening due to dust. It is found that, on average,…

1998 The Astronomical Journal
eHST 217
X-ray flare sparks quake inside Sun
DOI: 10.1038/30629 Bibcode: 1998Natur.393..317K

Kosovichev, A. G.; Zharkova, V. V.

Solar flares involve a release of the Sun's magnetic energy as X-radiation, particle beams and high-speed plasma flows. But we have discovered, using data from the Solar and Heliospheric Observatory (SOHO), that these flares also affect the Sun's interior, generating seismic waves similar to earthquakes. For example, a three-kilometre-high seismic…

1998 Nature
SOHO 217
Carbon Stars
DOI: 10.1146/annurev.astro.36.1.369 Bibcode: 1998ARA&A..36..369W

Knapp, Gillian R.; Wallerstein, George

Absolute magnitudes are estimated for carbon stars of various subtypes in the Hipparcos catalogue and as found in the Magellanic Clouds. Stellar radii fall within the limits of 2.4-4.7 AU. The chemical composition of carbon stars indicates that the C-N stars show nearly solar C/H, N/H, and ^12C/^13C ratios. This indicates that much of the C and N …

1998 Annual Review of Astronomy and Astrophysics
Hipparcos 215
HST/WFPC2 Observations of Warm Ultraluminous Infrared Galaxies
DOI: 10.1086/305028 Bibcode: 1998ApJ...492..116S

Sanders, D. B.; Veilleux, Sylvain; Mazzarella, J. M. +2 more

We present new high-resolution B- and I-band images of a nearly complete sample of nine ``warm'' (f25/f60 > 0.2), ultraluminous infrared galaxies (ULIGs) obtained with the Wide Field Planetary Camera of the Hubble Space Telescope (HST). The HST images clearly reveal the presence of tidal tails and other features associated…

1998 The Astrophysical Journal
eHST 213
The Luminosity Function and Initial Mass Function in the Galactic Bulge
DOI: 10.1086/300336 Bibcode: 1998AJ....115.1946H

Grillmair, Carl J.; Holtzman, Jon A.; Lynds, Roger +5 more

We present deep photometry obtained with the Hubble Space Telescope in a field in Baade's window in the Galactic bulge. We derive a luminosity function down to I ~ 24.3, or V ~ 27.5, corresponding to M ~ 0.3 M_⊙. The luminosity function from the turnoff down to this level appears remarkably similar to that observed in the solar neighborhood. We de…

1998 The Astronomical Journal
eHST 210