Search Publications
Tail lobe convection observed by Cluster/EDI
Nakamura, R.; Baumjohann, W.; Noda, H. +7 more
By using drift velocity data measured in the near-Earth tail lobe by the Electron Drift Instrument aboard the Cluster spacecraft, we study the average tail lobe convection of the Earth's magnetosphere. The data confirm the convection pattern toward the neutral sheet in the meridional (XZ) plane. By dividing the data according to the IMF clock angl…
An Astrometric Study of the Low-Mass Binary Star Ross 614
Han, Inwoo; Gatewood, George; Coban, Louis
Long accepted as the quintessential low-mass star, the secondary of the nearby diminutive astrometric binary Ross 614 has attracted considerable astrophysical interest. Unfortunately, the orbital period of 16.6 yr exceeds the duration of the mission-limited studies of most space-borne or instrumental-proving observational programs. As with most su…
On the origin of microwave type U-bursts
Kuznetsov, A. A.; Altyntsev, A. T.; Meshalkina, N. S. +1 more
An analysis is made of the observations of U-type cm-bursts recorded simultaneously with high spatial (Siberian solar radio telescope) and spectral resolution (National Astronomical Observatories/Beijing spectropolarimeters). It is shown that the source positions of increasing and decreasing branches of the U-burst coincide within a few arcsec. Th…
Voyager color photometry of Saturn's main rings: a correction
Showalter, Mark R.; Cuzzi, Jeffrey N.; Estrada, Paul R.
We correct a calibration error in our earlier analysis of Voyager color observations of Saturn's main rings at 14° phase angle (Estrada and Cuzzi, 1996, Icarus 122, 251) and present thoroughly revised and reanalyzed radial profiles of the brightness of the main rings in the Voyager green, violet, and ultraviolet filters and the ratios of these bri…
First results of a new 3-D model of the time-dependent modulation of electrons in the heliosphere
Fichtner, H.; Ferreira, S. E. S.; Potgieter, M. S. +2 more
We employ our recently developed ansatz for the time-dependent 3-D modelling of Jovian and galactic electrons in the inner heliosphere. The main goal of the study is to check whether the form of the diffusion tensofi as determined recently by Ferreira et al. (2001a,b) with an extended parameter study of the steady state is also useful for comparis…
An outflow from the nebula around the LBV candidate S 119
Weis, K.; Bomans, D. J.; Duschl, W. J.
We present an analysis of the kinematic and morphological structure of the nebula around the LMC LBV candidate S 119. On HST images, we find a predominantly spherical nebula which, however, seems to be much better confined in its eastern hemisphere than in the western one. The filamentary western part of the nebula is indicative of matter flowing …
The radial velocity curve of HD 153919 (4U 1700-37) revisited
van Kerkwijk, M. H.; Hammerschlag-Hensberge, G.; Kaper, L.
We have re-analysed all available high-resolution ultraviolet IUE spectra of the high-mass X-ray binary HD 153919/4U 1700-37. The radial velocity semi-amplitude of 20.6 +/- 1.0 km s-1 and orbital eccentricity of 0.22 +/- 0.04 agree very well with the values obtained earlier from optical spectra. They disagree with earlier conclusions fo…
Dynamic Modelling of the Hipparcos Attitude
van Leeuwen, Floor; Fantino, Elena
We present a new method for a high-accuracy reconstruction of the attitude for a slowly spinning satellite. This method, referred to as the fully-dynamic approach, explores the possibility to describe the satellite's attitude as that of a rigid body subject to continuous external torques. The method is tried out on the Hipparcos data and is shown …
H 2O- and OH-bearing minerals in the martian regolith: . analysis of 1997 observations from HST/NICMOS
Gordon, K. D.; Wolff, M. J.; Noe Dobrea, E. Z. +1 more
We have analyzed observations of the Acidalia hemisphere of Mars taken by the Hubble Space Telescope's Near-Infrared Camera Multi-Object Spectrograph (HST/NICMOS) during July of 1997 ( Ls=152°, northern martian summer). The data consist of images at ∼60 km/pixel resolution, using both narrow- and medium-band filters specifically selecte…
Deconstructing HD 28867
Walter, Frederick M.; Wolk, Scott J.; Morse, Jon A. +1 more
The 3" pair of B9 stars HD 28867 is one of the brightest X-ray sources in the Taurus-Auriga star-forming region. In this multiwavelength study, we attempt to deduce the source of the X-ray emission. We show that the east component is the X-ray source. The east component has a near-IR excess and displays narrow absorption lines in the optical, both…