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Small Solar Wind Transients and Their Connection to the Large-Scale Coronal Structure
Luhmann, J. G.; Russell, C. T.; Kilpua, E. K. J. +9 more
It has been realized for some time that the slow solar wind with its embedded heliospheric current sheet often exhibits complex features suggesting at least partially transient origin. In this paper we investigate the structure of the slow solar wind using the observations by the Wind and STEREO spacecraft during two Carrington rotations (2054 and…
Sedimentary deposits in Xanthe Terra: Implications for the ancient climate on Mars
Jaumann, R.; Scholten, F.; Neukum, G. +7 more
A variety of sedimentary deposits is observed in Xanthe Terra, Mars, including Gilbert-type deltas, fan deltas dominated by resedimentation processes, and alluvial fans. Sediments were provided through deeply incised valleys, which were probably incised by both runoff and groundwater sapping. Mass balances based on High-Resolution Stereo Camera (H…
Linking two consecutive nonmerging magnetic clouds with their solar sources
Zhukov, A. N.; Rodriguez, L.; Mandrini, C. H. +10 more
On 15 May 2005, a huge interplanetary coronal mass ejection (ICME) was observed near Earth. It triggered one of the most intense geomagnetic storms of solar cycle 23 (Dst peak = -263 nT). This structure has been associated with the two-ribbon flare, filament eruption, and coronal mass ejection originating in active region 10759 (NOAA …
The High-Mass End of the Black Hole Mass Function: Mass Estimates in Brightest Cluster Galaxies
Ferrarese, L.; Beifiori, A.; Dalla Bontà, E. +5 more
We present Hubble Space Telescope imaging and spectroscopic observations of three Brightest Cluster Galaxies, Abell 1836-BCG, Abell 2052-BCG, and Abell 3565-BCG, obtained with the Wide Field and Planetary Camera 2, the Advanced Camera for Surveys and the Space Telescope Imaging Spectrograph. The data provide detailed information on the structure a…
Automatic detection of sub-km craters in high resolution planetary images
Stepinski, Tomasz F.; Urbach, Erik R.
Impact craters are among the most studied geomorphic planetary features because they yield information about the past geological processes and provide a tool for measuring relative ages of observed geologic formations. Surveying impact craters is an important task which traditionally has been achieved by means of visual inspection of images. The s…
Isotropic Mid-Infrared Emission from the Central 100 pc of Active Galaxies
Telesco, C. M.; Packham, C.; Levenson, N. A. +3 more
Dust reprocesses the intrinsic radiation of active galactic nuclei (AGNs) to emerge at longer wavelengths. The observed mid-infrared (MIR) luminosity depends fundamentally on the luminosity of the central engine, but in detail it also depends on the geometric distribution of the surrounding dust. To quantify this relationship, we observe nearby no…
Near-Infrared Transit Photometry of the Exoplanet HD 149026b
Winn, Joshua N.; Holman, Matthew J.; Gilliland, Ronald +1 more
The transiting exoplanet HD 149026b is an important case for theories of planet formation and planetary structure, for the planet's relatively small size has been interpreted as evidence for a highly metal-enriched composition. We present observations of four transits with the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) on the Hubb…
Magellan Spectroscopy of Low-Redshift Active Galactic Nuclei
Ho, Luis C.; Kim, Minjin
We present an atlas of moderate-resolution (R ≈ 1200-1600) optical spectra of 94 low-redshift (z lsim 0.5) active galactic nuclei taken with the Magellan 6.5 m Clay Telescope. The spectra mostly cover the rest-frame region ~3600-6000 Å. All the objects have pre-existing Hubble Space Telescope imaging, and they were chosen as part of an ongoing pro…
Ionospheric storms on Mars: Impact of the corotating interaction region
Barabash, S.; Lundin, R.; Woch, J. +5 more
Measurements made by the ASPERA-3 and MARSIS experiments on Mars Express have shown, for the first time, that space weather effects related to the impact of a dense and high pressure solar wind (corotating interaction region) on Mars cause strong perturbations in the martian induced magnetosphere and ionosphere. The magnetic barrier formed by pile…
The High-Energy Emission of the Crab Nebula from 20 keV TO 6 MeV with Integral SPI
Jourdain, E.; Roques, J. P.
The SPI spectrometer aboard the International Gamma-Ray Astrophysics Laboratory mission regularly observes the Crab Nebula since 2003. We report on observations distributed over 5.5 years and investigate the variability of the intensity and spectral shape of this remarkable source in the hard X-rays domain up to a few MeV. While single power-law m…