Search Publications
Non-LTE CO limb emission at 4.7µm in the upper atmosphere of Venus, Mars and Earth: Observations and modeling
López-Puertas, M.; López-Valverde, M. A.; Gilli, G. +4 more
We report here on CO limb observations in Mars, Venus and Earth and their model simulations. A comparative study of the CO emission, including the most recent spacecraft observations of the three planets' atmospheres, has been performed. Strong daytime emissions near 4.7µm have been recently observed in the limb of the upper atmosphere of th…
Scattering particles in nightside limb observations of Venus’ upper atmosphere by Venus Express VIRTIS
Irwin, P. G. J.; Drossart, P.; Piccioni, G. +2 more
Nightside infrared limb spectra of the Venus upper atmosphere, obtained by Venus Express VIRTIS, show strong scattering of thermal radiation. This scattering of upward-going radiation into the line-of-sight is dominant below 82.5 km even at a wavelength of 5 µm, which is indicative of relatively large particles. We show that 1 µm-sized…
Improved measurement of Asteroid (4) Vesta’s rotational axis orientation
Russell, Christopher T.; Thomas, Peter C.; Li, Jian-Yang +6 more
We report an improved measurement of the rotational axis orientation of Asteroid (4) Vesta. By analyzing and combining all previous measurements using a limb-fitting technique from ground/HST data collected from 1983 to 2006, we derive a pole solution of (RA = 304.5°, Dec = 41.5°). Images of Vesta acquired with the Wide Field Camera 3 onboard the …
A multifrequency study of the active star-forming complex NGC 6357 - I. Interstellar structures linked to the open cluster Pis 24
Barbá, R.; Arnal, E. M.; Cappa, C. E. +4 more
We investigate the distribution of gas (ionized, neutral atomic and molecular) and interstellar dust in the complex star-forming region NGC 6357 with the goal of studying the interplay between the massive stars in the open cluster Pis 24 and the surrounding interstellar matter.
Our study of the distribution of the ionized gas is based on narr…Coronal mass ejection detection using wavelets, curvelets and ridgelets: Applications for space weather monitoring
Gallagher, P. T.; Young, C. A.; McAteer, R. T. J. +1 more
Coronal mass ejections (CMEs) are large-scale eruptions of plasma and magnetic field that can produce adverse space weather at Earth and other locations in the Heliosphere. Due to the intrinsic multiscale nature of features in coronagraph images, wavelet and multiscale image processing techniques are well suited to enhancing the visibility of CMEs…
XMM-Newton observation of the enigmatic object WR 46
Gosset, E.; Nazé, Y.; Rauw, G. +5 more
Aims: To further investigate the nature of the enigmatic object WR 46 and better understand the X-ray emission in massive stars and in their evolved descendants, we observed this variable object for more than two of its supposed cycles. The X-ray emission characteristics are appropriate indicators of the difference between a genuine Wolf-Raye…
Propagation of a shock-related disturbance in the Earth's magnetosphere
Santolík, O.; Palmroth, M.; Pulkkinen, T. I. +2 more
The Grand Unified Magnetosphere-Ionosphere Coupling Simulation, version 4, magnetohydrodynamic simulation of the interplanetary shock event on 9 November 2002 is used to determine the shock-associated disturbance propagation characteristics inside the Earth's magnetosphere. Interaction of an interplanetary fast forward shock with the magnetopause …
Ring-analysis flow measurements of sunspot outflows
Thompson, Michael J.; Featherstone, Nicholas A.; Hindman, Bradley W.
We present a local helioseismological analysis of the convective flows around sunspots. The flow deductions were obtained from MDI Dopplergrams using ring-analysis techniques to measure Doppler shifts induced in solar acoustic oscillations. A novel multi-scale 3-D inversion procedure was used to self-consistently combine all ring-analysis data tak…
Long term time variations of the suprathermal ions in Saturn's magnetosphere
Krimigis, S. M.; Mitchell, D. G.; Hamilton, D. C. +1 more
We use the Charge-Energy-Mass Spectrometer (CHEMS) on Cassini to study long-term time variations of the suprathermal (E/Q = 27-220 keV/e) ions in Saturn's equatorial ring current (Latitude = -10° to 10°, dipole L = 7-16) from the end of 2004 to the end of 2010. We identify five equatorial time periods, which vary in length from 124 to 282 days, an…
New Constraints on the Origin of the Short-term Cyclical Variability of the Wolf-Rayet Star WR 46
Talavera, A.; Pollock, A. M. T.; Hénault-Brunet, V. +3 more
The Wolf-Rayet star WR 46 is known to exhibit a very complex variability pattern on relatively short timescales of a few hours. Periodic but intermittent radial velocity shifts of optical lines as well as multiple photometric periods have been found in the past. Non-radial pulsations, rapid rotational modulation, or the presence of a putative low-…