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MASCOT: A Multi-Wavelength All-Sky Catalogue for Observations With Ground- and Space-Based Telescopes

Pasian, F.; Dluzhnevskaya, O.; Malkov, O.

New powerful observational techniques require a careful planning of observing programs. These requirements will be met within the proposed project MASCOT, A Multi-wavelength All-Sky Catalogue for Observations with ground- and space-based Telescopes. MASCOT will be based on the world's largest digitized all-sky survey containing astrometric and pho…

Wave signatures in the Jovian magnetosphere

Dougherty, Michele; Petkaki, Panagiota

Magnetometer data from the Ulysses Jupiter flyby are examined, in particular middle magnetosphere observations in the vicinity of the magnetodisk. Ion cyclotron waves are searched for in the heavy ion gyrofrequency regime (SO ⁺₂, SO ⁺, K ⁺, S ⁺, Na ⁺, O ⁺ and S ⁺⁺

Response of the radial stratification at the base of the convection zone to the activity cycle

Eff-Darwich, Antonio; Korzennik, Sylvain G.

We have analyzed the differences in the oscillation eigenfrequencies measured over more than two years of GONG observations (December 1995-April 1998) and SOI/MDI observations (May 1996-July 1998). We have inverted these data to look for signatures of the solar activity cycle on the stratification. A one-dimensional (radial) structure inversion co…

Erratum: Multi-component structure of solar and stellar transition regions

Peter, H.

Determination of optical positions for 23 extragalactic radio sources

Tang, Z. H.; Wang, S. H.; Jin, W. J.

The optical counterparts of 23 extragalactic radio sources, of which 13 are in the southern hemisphere, have been observed by three telescopes equipped with CCDs. By reference to the Astrographic/Tycho (ACT) Reference, Carlsberg Meridian (CMC),Positions and Proper Motions (PPM), Hipparcos (HIP) and Lick Northern Proper Motion (NPM) catalogues, the…

What we learn from quantitative ultraviolet spectroscopy of naked white dwarfs in cataclysmic variables

Long, Knox S.

Using the Hopkins Ultraviolet Telescope and Hubble Space Telescope, observers have now obtained UV spectra with sufficient signal to noise and resolution to allow quantitative spectroscopic analyses of the WDs in several DNe. In the "cleanest" DNe, such as U Gem, the observations are allowing the basic physical parameters of the WD - temperature, …

Interpreting the Mg IIh andk Line Profiles of Mira Variables

Wood, B. E.; Karovska, M.

We use radiative transfer calculations to reproduce the basic appearance of Mg II lines observed from Mira variables. These lines have centroids that are blueshifted by at least 30 km s^-1 from the stellar rest frame. It is unlikely that flow velocities in the stellar atmospheres are this fast, so radiative transfer effects must be respo…

Quiet-time periods observed by EPHIN/SOHO during the minimum of the 22nd solar cycle

Sierks, Holger; Gómez-Herrero, Raúl; Müller-Mellin, Reinhold +4 more

An analysis of the hydrogen and helium isotopic composition from EPHIN data, during the quiet-time period from January 1 to June 1, 1996, is presented. An isotopic discrimination and background rejection have been applied and relationships between the abundances of ²H/¹H, ³He/⁴He, and ⁴He/

The U.S. Naval Observatory pole-to-pole catalog: W2_J00

Rafferty, T. J.; Holdenried, E. R.

Between the years 1985 and 1996 the U.S. Naval Observatory (USNO), using two transit circles, one located in Washington, DC (U.S.A.) and the other in Blenheim, New Zealand, conducted an ambitious program of absolute observations of positions of celestial objects completely covering both hemispheres. Over 737 000 individual observations were made, …

The boron absorption line at 2089.6 Å in HD 140283?

Edvardsson, B.; Thorén, P.

We have observed the B i line at 2089.6 Å in the metal poor star HD 140283 with HST/STIS. The observation was an attempt to confirm the B abundances derived from the 2497 Å B i line in earlier works in general, and for for this star in particular (Edvardsson et al. 1994; Kiselman & Carlsson 1996). The resulting spectrum gained from 8 orbits of…