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HST FOC/48 UV imagery of GR8.

Dufour, R. J.; Wyatt, R. J.; Patterson, B.

Imagery observations of GR8 were made in July 1991 with the Hubble Space Telescope. The Wide Field Camera imaged the entire galaxy at 5500 Å (F555W), 4390 Å (F439W), and 3360 Å (F336W); and two smaller fields around the H II regions HL5 and HL19 were imaged at 1400 Å (F150W) with the Faint Object Camera. B and V magnitudes for these stars are from…

Ulysses observations of a pure electron event and its associated type III radio emission on December 15, 1990

Chaizy, P.; Pick, M.; Forsyth, R. +5 more

We describe an electron event associated with a type III burst observed by Ulysses. This event was observed when the spacecraft crossed the region of strong compression between a fast and a slow solar wind stream, characterized by a relatively high density and a complex behaviour of the plasma density, magnetic field and energetic electron anisotr…

Tuned Solar and Stellar Oscillations?

Doyle, J. G.; Andrews, A. D.

Einstein and EXOSAT observations of Geminga revisited

Bignami, G. F.; Mereghetti, S.; Caraveo, P.

We have re-analyzed the archive Einstein IPC and EXOSAT CMA x-ray data of Geminga, in the light of the recent discoveries on this source. The results of a search for the 237 msec periodicity are consistent with a pulsed fraction decreasing with x-ray energy. We have combined the EXOSAT CMA and the Einstein data in order to limit the spectral param…

The population of massive stars in R136 from HST/FOC UV observations

Leitherer, Claus; Nota, Antonella; de Marchi, Guido +2 more

New ultraviolet (λ≃1300 A, λ≃3400 A),HST FOC observations have been used to derive the UV color-magnitude diagram (CMD) of R136, with the main scientific goal of studying the upper end of the stellar mass function at ultraviolet wavelengths where the color degeneracy encountered in visual CMDs is less severe. The CMD has been compared to a set of …

The Decay Phase of the March-April, 1991 Low-Energy Particle Events Observed at Ulysses and Earth

Simnett, G. M.; Lanzerotti, L. J.; Armstrong, T. P. +2 more

Multiwavelength astronomy using ESIS

Giommi, P.; Ansari, S. G.

We present results on multi-frequency astronomy obtained using the European Space Information System, ESIS. ESIS is an ESA service designed to access, manipulate and combine archival data from a number of remote archives in the fields of Astronomy and Space Physics. The examples presented here include plots of radio-to-X-ray energy distribution of…

Multiwavelength monitoring of active galactic nuclei

Urry, C. M.

Recent multiwavelength monitoring of active galactic nuclei (AGN), particularly with the IUE satellite, has produced extraordinary advances in our understanding of the energy-generation mechanism(s) in the central engine and of the structure of the surrounding material. Examples discussed here include both ordinary AGN and blazars (the collective …

Ion Abundances in Solar Event at 5.3 AU

Tappin, S. J.; Lanzerotti, L. J.; Gold, R. E. +2 more

Ulysses Observations of Solar Wind Proton and Alpha Particle Temperatures and Anisotropies from 1 to 5 AU

McComas, D. J.; Goldstein, B. E.; Bame, S. J. +3 more