Search Publications
Magnetospheric feedback in solar wind energy transfer
Janhunen, P.; Lester, M.; Milan, S. E. +4 more
The solar wind kinetic energy fueling all dynamical processes within the near-Earth space is extracted in a dynamo process at the magnetopause. This direct energy transfer from the solar wind into the magnetosphere depends on the orientation of the interplanetary magnetic field (IMF) as well as other solar wind parameters, such as the IMF magnitud…
Population I Wolf-Rayet Runaway Stars: The Case of WR124 and its Expanding Nebula M1-67
Crowther, P. A.; Moffat, A. F. J.; Marchenko, S. V.
In 1997 and 2008 we used the WFPC2 camera on board the Hubble Space Telescope to obtain two sets of narrow-band Hα images of the runaway Wolf-Rayet (WR) star WR 124 surrounded by its nebula M1-67. This two-epoch imaging provides an expansion parallax and thus a practically assumption-free geometric distance to the nebula, d = 3.35 ± 0.67 kpc. Comb…
Lineated valley fill at the Martian dichotomy boundary: Nature and history of degradation
Neukum, G.; Hauber, E.; van Gasselt, S.
The fretted terrain of the Martian dichotomy boundary is a key region for investigating landforms related to creep of ice and debris as it exhibits landforms comparable to morphologies of periglacial environments. Although features known as lobate debris aprons, lineated valley fills and concentric crater fills have been studied in great detail, b…
Statistical study of low-frequency magnetic field fluctuations near Venus under the different interplanetary magnetic field orientations
Zhang, T. L.; Wang, C.; Baumjohann, W. +4 more
The magnetic field fluctuations near Venus are investigated in the frequency range 0.03-0.3 Hz on the basis of the measurements observed by Venus Express from April 2006 to December 2008. The data are sorted by the angle between interplanetary magnetic field (IMF) and solar wind flow. The spatial distributions of fluctuation properties under the d…
Solar-Wind Bulk Velocity Throughout the Inner Heliosphere from Multi-Spacecraft Measurements
Fedorov, A.; Barabash, S.; Sauvaud, J. -A. +6 more
We extrapolate solar-wind bulk velocity measurements for different in-ecliptic heliospheric positions by calculating the theoretical time lag between the locations. The solar-wind bulk velocity dataset is obtained from in-situ plasma measurements by STEREO A and B, SOHO, Venus Express, and Mars Express. During their simultaneous measurements betwe…
Weighing dark matter haloes with gravitationally lensed supernovae
Goobar, A.; Hook, I.; Mörtsell, E. +2 more
High-redshift Type Ia supernovae (SNe Ia) are likely to be gravitationally lensed by dark matter haloes of galaxies in the foreground. Since SNe Ia have very small dispersion after light-curve shape and colour corrections, their brightness can be used to measure properties of the dark matter haloes via gravitational magnification. We use observati…
Time-varying magnetospheric environment near Enceladus as seen by the Cassini magnetometer
Russell, C. T.; Dougherty, M. K.; Khurana, K. K. +3 more
In 2008, the Cassini spacecraft made four close Enceladus flybys along similar trajectories. During these flybys the magnetometer recorded the time-varying magnetic field associated with the plasma interaction with Enceladus and its plume. Close to Enceladus, the Cassini magnetometer observed 4% to 7% enhancement in the magnetic field magnitude, a…
Ultraviolet Spectra of the C-2003K7 Comet: Evidence for Dust Sublimation in Si and C Lines
Raymond, J. C.; Ciaravella, A.; Giordano, S.
UV spectra of the bright sungrazing comet C-2003K7 detected at 2.37 R sun above the Sun surface by the Ultraviolet Coronagraph Spectrometer (UVCS) during the daily synoptic scan show bright lines of H I Lyα, Si III λ 1206, and C III λ 977. The derived outgassing rate is an order of magnitude larger than those of the other sungrazers obs…
Observation of saturnian stream particles in the interplanetary space
Kempf, Sascha; Hsu, Hsiang-Wen; Jackman, Caitriona M.
In January 2004 the dust instrument on the Cassini spacecraft detected the first high-velocity grain expelled from Saturn - a so-called stream particle. Prior to Cassini's arrival at Saturn in July 2004 the instrument registered 801 faint impacts, whose impact signals showed the characteristic features of a high-velocity impact by a tiny grain. Th…
CoRoT 102931335: a candidate γ Dor in an eclipsing binary
Cardini, D.; Ribas, I.; Balaguer-Núñez, L. +3 more
We present an on-going study of CoRoT 102931335. Our preliminary results indicate that the target is an eclipsing binary system with an orbital period of