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Shock excitation of the knots of Hen 3-1475

Binette, L.; Raga, A. C.; Riera, A.

We present new optical STIS HST spectroscopic observations of the jets of the proto-planetary nebula Hen3-1475. The excitation conditions of the knots of Hen3-1475

are derived from the observed optical spectra, confirming that the knots are shock excited.

The shocked spectra are qualitatively reproduced by simple "3/2"Dbow shock models. …

APEX blind deconvolution of color Hubble space telescope imagery and other astronomical data

Carasso, Alfred S.

Photometric properties of Titan's surface from Cassini VIMS: Relevance to titan's hemispherical albedo dichotomy and surface stability

Sotin, C.; Brown, R. H.; Baines, K. H. +24 more

The Visual and Infrared Mapping Spectrometer (VIMS) instrument on the Cassini Saturn Orbiter returned spectral imaging data as the spacecraft undertook six close encounters with Titan beginning 7 July, 2004. Three of these flybys each produced overlapping coverage of two distinct regions of Titan's surface. Twenty-four points were selected on appr…

Limits to the abundance of surface CO₂ ice on Titan

Coustenis, A.; Dumas, C.; Hartung, M. +1 more

In the context of the Cassini/Huygens mission, we performed supporting ground-based observations to complement the results from the NASA/ESA/ASI space mission to the Saturnian system with particular focus on Titan. On the nights of 18 and 19 December 2004, we conducted adaptive optics observations with VLT/NACO to search for and map the distributi…

Global manifestations of a substorm onset observed by a multi-satellite and ground station network

Escoubet, C. P.; Liu, Z. X.; Frey, H. U. +6 more

With a favorable constellation of spacecraft and ground stations, a study is made on the global manifestations of a substorm onset. The onset occurred simultaneously and conjugately in both hemispheres, confirmed by observations of the auroral breakup from IMAGE FUV-WIC and a sudden intensification of a westward electrojet from ground-based magnet…

The extragalactic Cepheid bias: a new test using the period-luminosity-color relation

Paturel, G.; Teerikorpi, P.

We use the Period-Luminosity-Color relation (PLC) for Cepheids to test for the existence of a bias in extragalactic distances derived from the classical Period-Luminosity (PL) relation. We calculate the parameters of the PLC using several galaxies observed with the Hubble Space Telescope and show that this calculation must be conducted with a PLC …

Suzaku observation of NGC 3516: complex absorption and the broad and narrow Fe K lines

Miniutti, G.; Reeves, J. N.; Yaqoob, T. +9 more

We present preliminary results from a 150 ks Suzaku observation of the Seyfert 1 galaxy NGC 3516. Suzaku's wide bandpass has enabled us to deconvolve the broadband emitting and absorbing components in this object, breaking model degeneracies inherent in previous, smaller-bandpass spectra. The primary power-law continuum is absorbed by an ionized a…

Analysis of the Suzaku/XRS background

Ishisaki, Y.; Mitsuda, K.; Boyce, K. R. +14 more

Background counts on the XRS calorimeter spectrometer of the Suzaku Observatory (formerly Astro-E2) have several sources, including primary cosmic rays and secondary particles interacting with the pixels and with the silicon structure of the array. Using ground data, we identified the types of correlations between events on different pixels, and b…

Comparison of CME characteristics for SEP and non-SEP related events

Reinard, A. A.; Andrews, M. A.

A comparison is made between flare-associated CMEs that produce SEPs and those that do not to determine what role CME velocity, flare duration, and CME-flare time delays play in SEP production. 62 SEP events were selected from a list compiled by NOAA. The non-SEP list was made up of CMEs chosen to mimic the SEP-related CMEs as closely as possible …

Implication for the solar wind effect on the Io plasma torus

Kimura, T.; Misawa, H.; Yamamoto, H. +7 more

Sporadic enhancements of [SII] 673.1 nm emissions from the Io plasma torus were found in ground-based observations in 1998 and 1999. Just after the onset of the enhancement on September 21, 1999, narrow-band kilometric (nKOM) radiation began to be observed by the Galileo/PWS in the Jovian magnetosphere. During this period, quasi-periodic burst gro…