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First detection of hydroxyl in the atmosphere of Venus
Gondet, B.; Erard, S.; Drossart, P. +41 more
Context: Airglow emissions, such as previously observed from NO and O2(a-X) (0-0) on Venus, provide insight into the chemical and dynamical processes that control the composition and energy balance in the upper atmospheres of planets. The OH airglow emission has been observed previously only in the Earth's atmosphere where it has been used to infe…
Supernova 1996cr: SN 1987A's Wild Cousin?
Bauer, F. E.; Brandt, W. N.; Dwarkadas, V. V. +4 more
We report on new VLT optical spectroscopic and multiwavelength archival observations of SN 1996cr, a previously identified ultraluminous X-ray source known as Circinus galaxy X-2. Our optical spectrum confirms SN 1996cr as a bona fide Type IIn supernova, while archival imaging from the Anglo-Australian Telescope archive isolates the explosion date…
Charge-Coupled Device Speckle Observations of Binary Stars with the WIYN Telescope. V. Measures During 2001-2006
Horch, Elliott P.; van Altena, William F.; Cyr, William M., Jr. +3 more
A total of 1067 speckle observations of 345 binary stars are presented. Of these, 161 are double stars first resolved by Hipparcos, 17 are resolved for the first time in the observations presented here, and 21 are stars previously discovered by our program and reported in earlier papers in the series. In 947 cases, a magnitude difference is report…
Global and temporal variations in hydrocarbons and nitriles in Titan's stratosphere for northern winter observed by Cassini/CIRS
Fletcher, L.; Irwin, P. G. J.; Teanby, N. A. +8 more
Mid-infrared spectra measured by Cassini's Composite InfraRed Spectrometer (CIRS) between July 2004 and January 2007 ( L=293°-328°) have been used to determine stratospheric temperature and abundances of C 2H 2, C 3H 4, C 4H 2, HCN, and HC 3N. Over 65,000 nadir spectra wi…
On Lyman-line asymmetries in quiescent prominences
Heinzel, P.; Anzer, U.; Schmieder, B. +1 more
Aims: We study the asymmetries of the synthetic hydrogen Lyman lines and the process responsible for their formation.
Methods: To obtain the synthetic Lyman line profiles, we use a multi-thread prominence fine-structure model consisting of identical 2D threads. The 2D thread models are in MHS equilibrium, include an empirical prominence-corona…
Solar cycle changes, geomagnetic variations, and energetic particle properties in the inner magnetosphere
Baker, D. N.; Kanekal, S. G.
The causes and effects of geospace variability during recent years have been studied using coordinated measurements from an international constellation of Sun-Earth spacecraft. Particular emphasis is placed on long-term, homogeneous data sets from recent NASA spacecraft missions. It is found that even for modest geomagnetic storms, radiation belt …
Mapping dusty star formation in and around a cluster at z = 0.81 by wide-field imaging with AKARI
Oyabu, Shinki; Shimasaku, Kazuhiro; Koyama, Yusei +8 more
We present environmental dependence of dusty star-forming activity in and around the cluster RXJ1716.4+6708 at z = 0.81 based on wide-field and multiwavelength observations with the Prime Focus Camera on the Subaru Telescope (Suprime-Cam) and the Infrared Camera onboard the AKARI satellite. Our optical data show that the optical colour distributio…
The ultraluminous X-ray source NGC 1313 X-2. Its optical counterpart and environment
Motch, C.; Soria, R.; Böttcher, M. +4 more
NGC 1313 X-2 is one of the brightest ultraluminous X-ray sources in the sky, at both X-ray and optical wavelengths; therefore, quite a few studies of available ESO VLT and HST data have appeared in the literature. Here, we present our analysis of VLT/FORS1 and HST/ACS photometric data, confirming the identification of the B ~ 23 mag blue optical c…
The Complex Structure of the Cl 1604 Supercluster at z ~ 0.9
Kocevski, D.; Lemaux, B. C.; Lubin, L. M. +2 more
The Cl 1604 supercluster at z = 0.9 is one of a small handful of such structures discovered in the high-redshift universe and is the first target observed as part of the Observations of Redshift Evolution in Large Scale Environments (ORELSE) survey. To date, Cl 1604 is the largest structure mapped at z ~ 1, with the most constituent clusters and t…
Automated McIntosh-Based Classification of Sunspot Groups Using MDI Images
Colak, T.; Qahwaji, R.
This paper presents a hybrid system for automatic detection and McIntosh-based classification of sunspot groups on SOHO/MDI white-light images using active-region data extracted from SOHO/MDI magnetogram images. After sunspots are detected from MDI white-light images they are grouped/clustered using MDI magnetogram images. By integrating image-pro…