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The winds of hot close binaries. Paper 2: CW Cephei (HD 218066)

Stickland, D. J.; Pachoulakis, I.; Pfeiffer, R. J. +1 more

Determination of Position of Jupiter From Very-Long Baseline Interferometry Observations of ULYSSES

Mannucci, A. J.; Folkner, W. M.; McElrath, T. P.

Very-long baseline interferometry (VLBI) observations of the Ulysses spacecraft near its encounter with Jupiter on 1992 February 8 were made to determine the angular position of Jupiter with respect to well known extragalactic radio sources. Spacecraft range and Doppler data were used to determine the position of the spacecraft with respect to Jup…

Earth Rotation in the Hipparcos Reference Frame

Vondrák, J.; Ron, C.; Pešek, I.

New determination of the Earth orientation parameters (EOP), based on optical astrometry observations since the beginning of the century, is now under preparation by the Working group established by Commission 19 of the IAU. The Hipparcos catalog is to define the celestial reference frame in which the new series of EOP are to be described, The nov…

Dust Outflow Velocity of Comet Shoemaker-Levy 9

Hahn, Joseph M.; Rettig, Terrence W.; Sobczak, Gregory J.

Tidal dispersal of the dust comae of the ∼21 fragments of Comet Shoemaker-Levy 9 (S-L 9) became very pronounced in Hubble Space Telescope observations during the weeks prior to impact with Jupiter (T. W. Rettig, J. Hahn, S. C. Tegler, M. Mumma, and M. DiSanti 1994a,Periodic Comet Shoemaker-Levy 9(1993e), IAU Circular 6028; H. A. Weaver plus 20 oth…

Upstream and downstream propagating waves generated by pickup ions near comet Halley

Glassmeier, K. -H.; Neubauer, F. M.; Krauklis, I. +3 more

It is well known that most of the Alfvén waves generated in the solar wind by cometary ion pickup are propagating upstream in the solar wind reference frame. However, the magnitude of the small proportion propagating downstream is extremely important because it controls the amount of ion acceleration driven by the second order Fermi process. The v…

HST observations of the PG 1159 type central star of K1-16.

Patriarchi, P.; Perinotto, M.

The central star of the planetary nebula K1-16, belonging to the class of the pulsating PG 1159 pre-white dwarfs, has been observed with the HST telescope using the GHRS in the zone of the CIV λ1550A doublet, to ascertain the reality and examine the properties of the exceptionally fast wind suggested to occur in this star by low resolution IUE obs…

Solar cycle dependence of the solar wind dynamics: Pioneer, Voyager, and Ulysses from 1 to 5 AU

Smith, Edward J.; Américo González-Esparza, J.

An emission line region associated with 3C 273.

Meisenheimer, K.; Hippelein, H.; Roeser, H. J.

We have observed an extended emission line region about 4" to the South-East of 3C 273 in the light of the lines [OII]λ372.8nm and [OIII]λ500.7nm, with an overall linear dimension of ~20x10kpc and a brightness of ~10^-18^W/m^2^ in either line. HST images show the region to be split up into several knots. The line intensity ratios and colors are co…

A study of solar analogues in the ultraviolet.

Solano, E.; Wamsteker, W.; Fernley, J. +1 more

We have made a comparative study of the Sun and solar analogue stars using the published solar ultraviolet fluxes and IUE low dispersion spectra of the solar analogues. The Hyades dwarf HD 28099 (vB64) shows a flux excess below 2500A which is probably due to chromospheric activity since it is a relatively young star. HD 44594, 186408 (16CygA) and …

Optical positions of radio emitting stars.

Assafin, M.; Andrei, A. H.; Puliaev, S. P. +4 more

In order to contribute to the alignment of the radio and optical reference frames, 50 stars with confirmed radio emission and published radio positions were observed by astrographical means. Additionally, two confirmed radio-stars of fainter magnitude were observed using a CCD direct camera with a long focus, large aperture telescope. The reductio…