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µ Eridani from MOST and from the ground: an orbit, the SPB component's fundamental parameters and the SPB frequencies
Niemczura, E.; Leto, G.; Jerzykiewicz, M. +15 more
MOST time series photometry of µ Eri, an SB1 eclipsing binary with a rapidly rotating SPB primary, is reported and analysed. The analysis yields a number of sinusoidal terms, mainly due to the intrinsic variation of the primary, and the eclipse light curve. New radial-velocity observations are presented and used to compute parameters of a sp…
Herschel Observations Reveal Anomalous Molecular Abundances toward the Galactic Center
Lis, D. C.; Gerin, M.; Goicoechea, J. R. +4 more
We report the Herschel detections of hydrogen fluoride (HF) and para-water (p-H2O) in gas intercepting the sight lines to two well-studied molecular clouds in the vicinity of the Sgr A complex: G-0.02-0.07 (the "+50 km s-1 cloud") and G-0.13-0.08 (the "+20 km s-1 cloud"). Toward both sight lines, HF and water absor…
Comet 17P/Holmes: Contrast in Activity between before and after the 2007 Outburst
Hasegawa, Sunao; Usui, Fumihiko; Ootsubo, Takafumi +17 more
A Jupiter-family comet, 17P/Holmes, underwent outbursts in 1892 and 2007. In particular, the 2007 outburst is known as the greatest outburst over the past century. However, little is known about the activity before the outburst because it was unpredicted. In addition, the time evolution of the nuclear physical status has not been systematically st…
A large-scale flow vortex in the Venus plasma tail and its fluid dynamic interpretation
Barabash, S.; Lundin, R.; Futaana, Y. +3 more
We report on the existence of a large-scale ion flow vortex, a curled tailward flow of solar wind H+ (SW H+), and ionospheric O+ in the Venus plasma tail. The vortex commences at dusk (-Y), driven by a transverse (to the solar wind) aberration flow component. Dusk magnetosheath and ionospheric ions move westward ac…
Variable X-ray reflection from 1H 0419-577
Dewangan, Gulab C.; Pal, Main
We present detailed broad-band X-ray spectral variability of a Seyfert 1 galaxy 1H 0419-577 based on an archival Suzaku observation in 2007 July, a new Suzaku observation performed in 2010 January and the two latest XMM-Newton observations from 2010 May. All the observations show soft X-ray excess emission below 2 keV and both Suzaku observations …
CMEs and active regions on the sun
Yashiro, Seiji; Michalek, Grzegorz
The relationship between active regions (ARs) and coronal mass ejections (CMEs) is studied. For this purpose a statistical analysis of 694 CMEs associated with ARs was carried out. We considered the relationship between properties of the CMEs and ARs characterized using the McIntosh classification. We demonstrated that CMEs are likely to be launch…
Dust and spacecraft charging in Saturn's E ring
Kempf, Sascha; Horányi, Mihály; Hsu, Hsiang-Wen
The electrostatic potential of a spacecraft reflects the local physical conditions and also affects the in situ thermal plasma measurements. In this work we focus on the spacecraft charging in the high dust density region near Enceladus in Saturn's E ring. In a dust-rich environment, the spacecraft charging is modified by the complex (dusty) plasm…
Another Brick in Understanding Chemical and Kinematical Properties of BSSs: NGC 6752
Dalessandro, E.; Mucciarelli, A.; Ferraro, F. R. +2 more
We used high-resolution spectra acquired with the multifiber facility FLAMES at the Very Large Telescope of the European Southern Observatory to investigate the chemical and kinematical properties of a sample of 22 blue straggler stars (BSSs) and 26 red giant branch stars in the nearby globular cluster NGC 6752. We measured radial and rotational v…
Evidence of Non-thermal X-Ray Emission from HH 80
Miceli, M.; Bonito, R.; Albacete-Colombo, J. F. +4 more
Protostellar jets appear at all stages of star formation when the accretion process is still at work. Jets travel at velocities of hundreds of km s-1, creating strong shocks when interacting with the interstellar medium. Several cases of jets have been detected in X-rays, typically showing soft emission. For the first time, we report ev…
Tidal Tails of Minor Mergers. II. Comparing Star Formation in the Tidal Tails of NGC 2782
Knezek, Patricia M.; Charlton, Jane; Scowen, Paul +5 more
The peculiar spiral NGC 2782 is the result of a minor merger with a mass ratio ~4: 1 occurring ~200 Myr ago. This merger produced a molecular and H I-rich, optically bright eastern tail and an H I-rich, optically faint western tail. Non-detection of CO in the western tail by Braine et al. suggested that star formation had not yet begun. However, d…