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Optical Positions of 44 Radio Stars from Astrolabe Observations

Wang, Rui; Hu, Hui; Li, Xiaoming

The observations made with the photoelectric astrolabe at Yunnan Observatory since 1986 have been reprocessed in the Hipparcos Catalogue, and the optical positions of 44 radio stars obtained. These are all the stars in common with the Hipparcos Catalogue.

Photometry of Hipparcos Variable Stars

Stencel, Robert E.; Ostrowski, Therese A.

Among the discoveries reported by the Hipparcos team was the detection of short-term photometric fluctuations in several long period, or Mira, variables (de Laverny et al. 1998). Nearly 15 percent of the 250 Miras surveyed in the broadband 380 to 800 nm filter showed variation of 0.2 to 1.1 magnitudes on timescales of 2 to 100 hours, preferentiall…

Gravitational Lens Candidates in the HST Survey of BL Lac Objects

Falomo, R.; Treves, A.; Urry, C. M. +5 more

Catching the solar breeze.

Marsden, R.

The spacecraft Ulysses is investigating what lies between us and the stars.

The Cosmic Ray Radial and Latitudinal Intensity Gradients in the Inner and Outer Heliosphere over the Cycle 22 Solar Minimum

Kunow, H.; Muller-Mellin, R.; Wibberenz, G. +7 more

The spatial intensity gradients of galactic and anomalous cosmic ray helium are studied over the 1993.0- 1998.0 time period using data from cosmic ray experiments on IMP 8, Ulysses, Voyagers 1 and 2 and Pioneer 10. The present study differs from those presented previously in that a different analysis mode has been selected for the Voyager 2 measur…

Eight Gyr Minimum Disk Age from Hipparcos

Jimenez, Raul; Flynn, Chris; Kotoneva, Eira

A comparison between the FK5 and Hipparcos catalogues.

Lu, Peizhen; Xu, Tongqi

Through a comparison between the FK5 and Hipparcos catalogues at different epochs, the systematic differences of FK5 are tested and discussed. This shows that the systematic differences in proper motions of FK5 seem to be the primary origin which affects the systematic differences in positions of FK5. In some researches on the secular variation of…

The corona and the solar wind as a manifestation of the solar high speed mass emanation.

Nikolskaya, K. I.; Valchuk, T. E.

A concept of the solar corona and the solar wind resulting from the interaction between the solar primary high speed mass emanation and over-photospheric magnetic fields is outlined and developed. The model arises from the recent view of the solar corona spatial structure and Ulysses solar wind measurement data. The initial solar fast outflow is f…

A CDS Observation of the Relationship Between a Coronal Hole and Chromospheric Structure

Insley, Jude E.

This paper studies the relationship between chromospheric structure and the location of the coronal hole boundary, using a SOHO-CDS observation made on 13 June 1996. The cell structure visible in the oxygen and helium data is smoothed and a basin algorithm is used to find the individual cells. As the smoothing scale increases, cells merge to form …

Gamma Ray Measurements of the 1991 November 15 Solar Flare

Ryan, J. M.; Bennett, K.; Rank, G. +6 more

The 1991 November 15 X1.5 flare is a well observed event. Comprehensive data from ground-based observatories and the Yohkoh, PVO, and Ulysses spacecrafts provide the basis for a contextual interpretation of gamma-ray spectra and light-curves from the Compton Observatory. In particular, spectral, spatial, and temporal data at several energies are n…