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Motion of the Heliospheric Termination Shock at High Heliographic Latitude
Barnes, Aaron
We expect the mean distance of the heliospheric termination shock to be greater (smaller) at polar latitudes than at equatorial latitudes, depending on whether the mean dynamic pressure of the solar wind is greater or smaller at high latitudes. The heliospheric termination shock is expected to move in response to variation in upstream solar wind c…
Discovery of Extreme-Ultraviolet Radiation from the Seyfert Galaxy Ton S180 (= EUVE J0057-223)
Thorstensen, John R.; Bowyer, Stuart; Vennes, Stephane +1 more
We report the detection of intense EUV radiation from the Seyfert 1 galaxy Ton S180. The source EUVE J0057-223, discovered in the Extreme-Ultraviolet Explorer all-sky survey, is only 25" away from its optical counterpart, well within the position error circle. We present a complete broadband energy distribution of Ton S180 using infrared (IRAS), o…
A Multiwavelength Investigation of the Merging Galaxy HCG 95C
Papaderos, P.; Schultz, A.; Fink, U. +7 more
The compact group HCG 95 consists of four galaxies in which two of the members, HCG 95a and HCG 95c, are interacting. The morphology suggests the interaction is well evolved with the Northern tidal arm of HCG 95c overlapping the Eastern edge of HCG 95a. A linear bridge connecting the two galaxies hints at nuclear activity within HCG 95c. Our color…
Structure and Photometry of an I < 20.5 Galaxy Sample from the Hubble Space Telescope Medium Deep Survey
Illingworth, Garth D.; Forbes, Duncan A.; Bershady, Matthew A. +5 more
A set of 100 faint galaxies from nine Hubble Space Telescope Wide Field Camera I-band images have been analyzed as part of the Medium Deep Survey (MDS) Key Project. This sample reaches a depth of I <~ 20.5 (corresponding to B ~ 22-23) and complements the first set of fainter galaxies analyzed by the MDS team. Images were deconvolved using the L…
Latitudinal Effects of Galactic Cosmic Rays Observed Onboard the Ulysses Spacecraft
Sierks, H.; Kunow, H.; Heber, B. +7 more
The propagation of sub-MeV solar electrons to heliolatitudes above 50°S
Simnett, G. M.; Pick, M.; Kerdraon, A. +5 more
On 27 February 1994 when the Ulysses spacecraft was at an heliolatitude of 54°S low energy electrons (∼50-400 keV) and high energy protons (14-31 MeV) were measured following a solar flare beyond the west limb. These measurements show that under favorable conditions energetic particles can be transported very rapidly across 60 degrees in heliocent…
HST polarization map of the ultraviolet emission from the outer jet in M87 and a comparison with the 2-cm radio emission
Boksenberg, A.; Mackay, C. D.; Tanvir, N. R. +2 more
We present the first high-resolution polarization map of the ultraviolet emission from the outer jet in M87. The data were obtained by the Faint Object Camera (FOC) on the Hubble Space Telescope. The polarization map has a resolution of 0.2 arcsec and was derived using data from three linearly polarized images combined with the best available cali…
Faint Object Spectrograph Observations of MRK 509: Ultraviolet Absorption Lines Near the Redshift of the Seyfert Galaxy
Crenshaw, D. Michael; Wu, Chi-Chao; Boggess, Albert
Ultraviolet spectra of the Seyfert 1 galaxy Mrk 509 have been obtained with the Faint Object Spectrograph on the Hubble Space Telescope. The spectra show strong absorption lines in the cores of the redshifted emission lines of Lyα and C IV λλ1548.2, 1550.8, confirming an earlier detection in IUE high-dispersion spectra, and a new detection of stro…
SOHO Ground Segment, Science Operations, and Data Products
St. Cyr, O. C.; Gurman, J. B.; Martens, P. C. H. +2 more
We describe the ground segment, pre-launch operations concepts, and data products supporting the SOHO mission. Our goal is threefold: first, we provide a historical view of the design and development of the systems described here, as a background perspective to those who will use the system and those who may build such systems for future missions.…
Latitudinal Variations in the Solar Wind Electron Heat Flux
Scime, Earl E.; Bame, Samuel J.; Phillips, John L. +1 more
Ulysses measurements of the solar wind electron heat flux as a function of heliographic latitude are presented. The latitudinal in the electron heat flux presented have been normalized by the radial gradient in the electron heat flux obtained during the in-ecliptic phase of the Ulysses mission (qe∼ R-3.0). We find no signific…