Search Publications
Missions
Journals
Publication Years
Seasonal evolution of Titan's dark polar hood: midsummer disappearance observed by the Hubble Space Telescope
Lorenz, Ralph D.; Lemmon, Mark T.; Smith, Peter H.
Titan, Saturn's largest moon, has a dense organic-laden atmosphere that displays dramatic seasonal variations in composition and appearance. Here we document the evolution of the dark polar hood, first seen in 1980 by Voyager 1 around the north pole, and report quantitative measurements of the hood's disappearance from the south pole in 2002-2003 …
Automated Detection of EUV Prominences
Foullon, C.; Verwichte, E.
We present methods to detect automatically off-limb prominences in the extreme ultraviolet (EUV), using synoptic images taken by the extreme-ultraviolet imaging telescope (EIT) on board SOHO. The 304 Å line is essential for the detection of EUV prominences, but the optimal detection is achieved through a combined image processing of the four synop…
Warm molecular gas in the envelope and outflow of IRAS 12496-7650 (DK Chamaeleontis)
van Dishoeck, E. F.; Schilke, P.; Güsten, R. +3 more
Aims.To obtain insight into the physical structure of the warm gas in the inner envelope of protostars and the interaction with the outflow.
Methods: .Sub-millimeter observations of 12CO, 13CO and/or C18O in J=3-2, J=4-3 and J=7-6 were obtained with the APEX Telescope towards IRAS 12496-7650, an intermediate ma…
Oxygen Abundance and Energy Deposition in the Slow Coronal Wind
Abbo, L.; Antonucci, E.; Telloni, D.
Observations of the extended corona obtained with the Ultraviolet Coronagraph Spectrometer (UVCS) on board the Solar and Heliospheric Observatory (SOHO) during the solar minimum years 1996 and 1997 have been analyzed to derive the oxygen abundance in the outer corona. A comparison of the absolute coronal abundance, measured in the coronal regions …
Cluster observation of plasma flow reversal in the magnetotail during a substorm
Livi, S.; Kistler, L. M.; Dunlop, M. W. +7 more
We investigate in detail a reversal of plasma flow from tailward to earthward detected by Cluster at the downstream distance of ~19 RE in the midnight sector of the magnetotail on 22 August 2001. This flow reversal was accompanied by a sign reversal of the Bz component and occurred during the late substorm expansion phase as …
Solar wind responses to the solar activity cycle
Marsch, Eckart
The solar magnetic field and the plasma properties, such as the temperature and density distributions in the solar corona, determine the solar wind stream structure and the extent and dynamics of the entire heliosphere, including its global magnetic field. The variation of the solar wind (coming in the form of steady fast streams, variable slow fl…
Rotation of the magnetic field in Earth's magnetosheath by bulk magnetosheath plasma flow
Lucek, E. A.; Schwartz, S. J.; Longmore, M.
Orientations of the observed magnetic field in Earth's dayside magnetosheath are compared with the predicted field line-draping pattern from the Kobel and Flückiger static magnetic field model. A rotation of the overall magnetosheath draping pattern with respect to the model prediction is observed. For an earthward Parker spiral, the sense of the …
Opacity in the upper atmospheres of active stars. II. AD Leonis
Christian, D. J.; Mathioudakis, M.; Bloomfield, D. S. +4 more
We present FUV and UV spectroscopic observations of AD Leonis, with the aim of investigating opacity effects in the transition regions of late-type stars. The C III lines in FUSE spectra show significant opacity during both the quiescent and flaring states of AD Leonis, with up to 30% of the expected flux being lost during the latter. Other FUSE e…
The proper motion of the isolated neutron star RX J1605.3+3249
de Luca, A.; Mignani, R. P.; Zane, S. +1 more
Aims.We present a new optical observation of the X-ray dim isolated neutron star RX J1605.3+3249, performed in 2005 with the Wide Field Channel (WFC) of the Advanced Camera for Surveys (ACS) on board Hubble Space Telescope, aimed at measuring the neutron star proper motion.
Methods: .We have compared the target position with the one measured i…
Study of whistler mode instability in Saturn's magnetosphere
Singhal, R. P.; Tripathi, A. K.
A dispersion relation for parallel propagating whistler mode waves has been applied to the magnetosphere of Saturn and comparisons have been made with the observations made by Voyager and Cassini. The effect of hot (suprathermal) electron-density, temperature, temperature anisotropy, and the spectral index parameter, κ, on the temporal growth rate…