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Eclipse observations of coronal plumes in the past and in future

Gulyaev, R. A.

Some historic fragments of eclipse investigations of polar coronal plumes are presented. New data of fundamental significance have been obtained recently thanks to the SOHO space observatory. Detection of polar plumes penetrating through the whole space of polar coronal holes is one of the most important results of the SOHO mission. It is suggeste…

Large-Scale Polar Coronal Magnetic Field Model and the Expected August 11, 1999 Eclipse Corona

Zhukov, A. N.; Koutchmy, S.; Veselovsky, I. S. +1 more

We compare available SOHO/LASCO C2 images with the model calculations of the large-scale coronal magnetic field near the magnetic poles of the Sun. The model field consists of the ones of the dipole and of the thin current sheet in the plane perpendicular to the dipole. The positions of the dipole and the current sheet (representing the heliospher…

Saturn, Titan, and the Cassini-Huygens mission

Zarnecki, J.

Low Energy (0.5-5.0 MeV/nuc) Anomalous Cosmic Rays at High Heliolatitudes and in the Ecliptic Plane

Gold, R. E.; Maclennan, C. G.; Lanzerotti, Louis J.

In 1997 to early 1998, anomalous cosmic ray (ACR) oxygen (O) was measured by the HI-SCALE instrument on the Ulysses spacecraft at 5 AU in the ecliptic plane for the energy range 0.5-5.0 MeV/nuc. At 1 AU in the ecliptic at this time (measured by the EPAM instrument on the ACE spacecraft) ACR O was only seen in the energy range 2-5 MeV/nuc. The radi…

Corotating Interaction Regions in the Heliosphere:Workshop Report

Kunow, Horst

In June 1998 a workshop was held at the International Space Science Institute ISSI, Bern, Switzerland, on "Development and effects of Corotating Interaction Regions in the Heliosphere". The workshop was the last of a series of three and the results will be published shortly in Space Science Rewiews and in the Space Science Series of ISSI. The deve…

Zero points of the magnetic field in the solar atmosphere

Filippov, B. P.

Examples of saddle structures observed in images of the Sun in Hα, soft X-ray (YOHKOH SXT), and ultraviolet (SOHO EIT) emission are presented. Since the plasma distribution is controlled by the magnetic field, the saddles testify to the presence of hyperbolic singularities in the magnetic field. Such singularities play an important role in the the…

The Hipparcos satellite: a wealth of new astrophysical results.

Turon, C.

The European Space Agency satellite Hipparcos was the first satellite to accurately measure angular displacements on the sky. The mission results deal with a great variety of subjects: reference systems, stellar physics and evolution, galactic kinematics, dynamics and evolution, distance and age scale in the Universe. A selection of the most strik…

A serendipitous observation of the gamma-ray burst GRB 921013b field with EUVE

Hurley, K.; Bowyer, S.; Lund, N. +3 more

We report a serendipitous extreme ultraviolet observation by EUVE of the field containing GRB 921013b, ~ 11 hours after its occurrence. This burst was detected on 1992 October 13 by the WATCH and PHEBUS on Granat, and by the GRB experiment on Ulysses. The lack of any transient (or quiescent) EUV source imposes a 2sigma upper limit of 1.3 x 10(-12)…

Propagation upstream from the shock of the High Latitude, Ulysses, CIR associated particle increases

Franz, M.; Blake, B.; Quenby, John +2 more

The first high solar latitude pass of the Ulysses spacecraft revealed the presence of MeV particle increases up to latitudes above 60 degrees, well outside the CIR belt but associated in time with the regular passage of these plasma interfaces at more equatorial latitudes. The particle increases have been explained variously as due to diffusion fr…

The New Sun - Probing Solar Plasmas with the SUMER Instrument on SOHO

Curdt, W.

With the SUMER (Solar Ultraviolet Measurements of Emitted Radiation) spectrometer on SOHO we observe the solar atmosphere with high spectral, spatial, and temporal resolution in the 400 to 1600 Å wavelength range. Selected observational facts are presented. Among these are points concerning the solar EUV spectrum in general, such as line identific…