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Response of Jupiter's and Saturn's auroral activity to the solar wind
Crary, F.; Cecconi, B.; Lamy, L. +18 more
While the terrestrial aurorae are known to be driven primarily by the interaction of the Earth's magnetosphere with the solar wind, there is considerable evidence that auroral emissions on Jupiter and Saturn are driven primarily by internal processes, with the main energy source being the planets' rapid rotation. Prior observations have suggested …
Binary planetary nebulae nuclei towards the Galactic bulge. II. A penchant for bipolarity and low-ionisation structures
Miszalski, B.; Moffat, A. F. J.; Parker, Q. A. +1 more
Considerable effort has been applied towards understanding the precise shaping mechanisms responsible for the diverse range of morphologies exhibited by planetary nebulae (PNe).
At least 10-20% of PNe have central stars (CSPN) with a close binary companion thought responsible for heavily shaping the ejected PN during common-envelope (CE) evol…Clumpy Galaxies in Goods and Gems: Massive Analogs of Local Dwarf Irregulars
Elmegreen, Bruce G.; Elmegreen, Debra Meloy; Marcus, Max T. +3 more
Clumpy galaxies in the Galaxy Evolution from Morphology and SEDs and Great Observatories Origins Deep Survey fields are examined for clues to their evolution into modern spirals. The magnitudes of the clumps and the surface brightnesses of the interclump regions are measured and fitted to models of stellar age and mass. There is an evolutionary tr…
Characteristics of solar-like oscillations in red giants observed in the CoRoT exoplanet field
Baudin, F.; Hatzes, A. P.; Baglin, A. +6 more
Context: Observations during the first long run (~150 days) in the exo-planet field of CoRoT increase the number of G-K giant stars for which solar-like oscillations are observed by a factor of 100. This opens the possibility to study the characteristics of their oscillations in a statistical sense.
Aims: We aim to understand the statistical d…
CME interactions with coronal holes and their interplanetary consequences
Gopalswamy, N.; Yashiro, S.; Mäkelä, P. +2 more
A significant number of interplanetary shocks (~17%) during cycle 23 were not followed by drivers. The number of such ``driverless'' shocks steadily increased with the solar cycle with 15%, 33%, and 52% occurring in the rise, maximum, and declining phase of the solar cycle. The solar sources of 15% of the driverless shocks were very close the cent…
Solar Irradiance Reference Spectra (SIRS) for the 2008 Whole Heliosphere Interval (WHI)
Chamberlin, Phillip C.; Woods, Thomas N.; Eparvier, Francis G. +6 more
The IHY2007 Whole Heliosphere Interval (WHI) for solar Carrington Rotation 2068 (20 March to 16 April 2008) has been very successful in obtaining a wide variety of solar, heliospheric, and planetary observations during times of solar cycle minimum conditions. One of these efforts is the generation of solar irradiance reference spectra (SIRS) from …
A Compton-thick Wind in the High-luminosity Quasar, PDS 456
Behar, E.; Turner, T. J.; Fabian, A. C. +7 more
PDS 456 is a nearby (z = 0.184), luminous (L bol ~ 1047 erg s-1) type I quasar. A deep 190 ks Suzaku observation in 2007 February revealed the complex, broadband X-ray spectrum of PDS 456. The Suzaku spectrum exhibits highly statistically significant absorption features near 9 keV in the quasar rest frame. We show …
Density and temperatures of the upper Martian atmosphere measured by stellar occultations with Mars Express SPICAM
Montmessin, Franck; Bertaux, Jean-Loup; González-Galindo, Francisco +6 more
We present one Martian year of observations of the density and temperature in the upper atmosphere of Mars (between 60 and 130 km) obtained by the Mars Express ultraviolet spectrometer Spectroscopy for Investigation of Characteristics of the Atmosphere of Mars (SPICAM). Six hundred sixteen profiles were retrieved using stellar occultations techniq…
Quantitative Measurements of Coronal Mass Ejection-Driven Shocks from LASCO Observations
Vourlidas, Angelos; Ontiveros, Veronica
In this paper, we demonstrate that coronal mass ejection (CME)-driven shocks can be detected in white light coronagraph images and in which properties such as the density compression ratio and shock direction can be measured. Also, their propagation direction can be deduced via simple modeling. We focused on CMEs during the ascending phase of sola…
High-precision density measurements in the solar corona. I. Analysis methods and results for Fe XII and Fe XIII
Young, P. R.; Mariska, J. T.; Hara, H. +1 more
Aims: The EUV Imaging Spectrometer (EIS) instrument on board the Hinode satellite has access to some of the best coronal density diagnostics, and the high sensitivity of the instrument now allows electron number density, N_e, measurements to an unprecedented precision of up to ±5% in active regions. This paper gives a thorough overview of data ana…