Search Publications
Evidence for layered methane clouds in Titan’s troposphere
Atreya, Sushil K.; Wang, Chia C.; Signorell, Ruth
Layered methane clouds in Titan's troposphere with an upper methane ice cloud, a lower liquid methane-nitrogen cloud, and a gap in between were suggested from in situ measurements and ground-based observations. Here we report laboratory investigations under conditions that mimic Titan's troposphere providing a detailed picture of the cloud layers.…
The spectrum of a Saturn ring spoke from Cassini/VIMS
Brown, R. H.; Nicholson, P. D.; Bellucci, G. +7 more
On 2008, July, the Cassini/VIMS spectrometer detected spokes on the Saturn's B ring for the first time. These are the first measurements of the complete reflectance spectrum of the spokes in a wide spectral range (0.35-0.51 µm). Here we will focus on a single broad-shaped spoke, imaged by VIMS on July, 9. Radiative transfer modeling supports…
Simultaneous X-ray and Ultraviolet Observations of the SW Sextantis Star DW Ursae Majoris
Dhillon, V. S.; Szkody, Paula; Hoard, D. W. +6 more
We present the first pointed X-ray observation of DW Ursae Majoris, a novalike cataclysmic variable (CV) and one of the archetype members of the SW Sextantis class, obtained with the XMM-Newton satellite. These data provide the first detailed look at an SW Sex star in the X-ray regime (with previous X-ray knowledge of the SW Sex stars limited prim…
The central region of spiral galaxies as seen by Herschel. M 81, M 99, and M 100
Elbaz, D.; Bock, J. J.; Clements, D. L. +57 more
With appropriate spatial resolution, images of spiral galaxies in thermal infrared (~10 µm and beyond) often reveal a bright central component, distinct from the stellar bulge, superimposed on a disk with prominent spiral arms. ISO and Spitzer studies have shown that much of the scatter in the mid-infrared colors of spiral galaxies is relate…
A Multi-wavelength Approach to the Properties of Extremely Red Galaxy Populations. I. Contribution to the Star Formation Rate Density and Active Galactic Nucleus Content
Alexander, D. M.; Mobasher, B.; Messias, H. +3 more
We present a multi-wavelength analysis of the properties of extremely red galaxy (ERG) populations, selected in the GOODS-South/Chandra Deep Field South field. By using all the photometric and spectroscopic information available on large deep samples of extremely red objects (EROs; 645 sources), IRAC EROs (IEROs; 294 sources), and distant red gala…
Multifrequency nature of the 0.75 mHz feature in the X-ray light curves of the nova V4743 Sgr
Ness, J. -U.; Dobrotka, A.
We present timing analyses of eight X-ray light curves and one optical/UV light curve of the nova V4743 Sgr (2002) taken by Chandra and XMM-Newton on the following days after outburst: 50 (early hard emission phase), 180, 196, 302, 371, 526 [super soft source (SSS) phase], and 742 and 1286 (quiescent emission phase). We have studied the multifrequ…
On arc-polarized structures in the solar wind
Haaland, S. E.; Paschmann, G.; Sonnerup, B. U. Ö.
A theoretical model is proposed to account for some of the behavior of arc-polarized magnetic structures seen in the solar wind. To this end, an exact analytical solution is developed that describes infinite plane wave trains of arbitrary amplitude in a plasma governed by ideal Hall MHD. The main focus is on intermediate-mode wave trains, which di…
Stars outside the Hipparcos list closely encountering the Solar system
Bobylev, V. V.
Based on currently available kinematic data, we have searched for stars outside the Hipparcos list that either closely encountered in the past or will encounter in the future the Solar system within several parsecs. For the first time, we have identified two single stars, GJ 3379 (G 099-049) and GJ 3323 (LHS 1723), as candidate for a close encount…
A tropical haze band in Titan’s stratosphere
Irwin, P. G. J.; Teanby, N. A.; de Kok, R. +7 more
Inspection of near-infrared images from Cassini's Imaging Science Subsystem and Visual and Infrared Mapping Spectrometer have revealed a new feature in Titan's haze structure: a narrow band of increased scattering by haze south of the equator. The band seems to indicate a region of very limited mixing in the lower stratosphere, which causes haze p…
Scattering Polarization in the Fe I 630 nm Emission Lines at the Extreme Limb of the Sun
Lites, B. W.; Ichimoto, K.; Ishikawa, R. +6 more
Spectro-polarimetric observations with the Solar Optical Telescope onboard Hinode reveal the emission spectrum of the Fe I 630 nm lines at the solar limb. The emission shell extends for less than 1'' thereby making it extremely difficult to detect from ground-based observatories viewing the limb through the Earth's atmosphere. The linear polarizat…