Search Publications
Enceladus plume density from Cassini spacecraft attitude control data
Lorenz, Ralph D.; Burk, Thomas A.
The plumes of Enceladus are of interest both as a geophysical phenomenon, and as an astrobiological opportunity for sampling internal material. Here we report measurements of the total mass density (gas plus dust, a combination not reported before except in the engineering literature) deduced from telemetry of Cassini's Attitude and Articulation C…
Spectra of Turbulence during the Dipolarization of the Magnetic Field
Kozak, L.; Petrenko, B.; Kronberg, E. +3 more
The presence of heterogeneity in turbulent processes has been analyzed, and the spectra of turbulence have been obtained for the regions before and during the dipolarization of the magnetic field in the Earth's magnetospheric tail from the measurements of four space vehicles of the Cluster-2 mission (the event of September 21, 2005). The spectral …
Planetary nebulae in the circumnuclear region of M31: a spectroscopic sample
Dong, Hui; Li, An-Qi; Li, Zhi-Yuan +2 more
Planetary nebulae (PNe) are an important tool for studying the dynamics and chemical evolution of galaxies in the Local Universe, given their characteristic bright emission line spectra. The Andromeda Galaxy (M31) provides a unique laboratory for studying PNe in the circumnuclear region, thanks to its proximity and almost uniformly low line-of-sig…
Evolution of the Outflows in NGC 3516
Kraemer, S. B.; Dunn, Jay P.; Parvaresh, Rozhin +1 more
We analyze the 2011 HST/COS spectrum of the Seyfert 1 galaxy NGC 3516, which demonstrates clear changes in one of the intrinsic absorption troughs (component 5), slight evidence of change in a second trough (component 6), and the appearance of a new absorption trough (component 9). We interpret both the changes and the appearance of the new trough…
Dust Production Rates in the Fomalhaut Debris Disk from SOFIA/FORCAST Mid-infrared Imaging
Lau, R. M.; Herter, T. L.; Adams, J. D. +2 more
We present the first spatially resolved mid-infrared (37.1 µm) image of the Fomalhaut debris disk. We use point spread function fitting and subtraction to distinctly measure the flux from the unresolved component and the debris disk. We measure an infrared excess in the point source of 0.9 ± 0.2 Jy, consistent with emission from warm dust in…
Statistical Similarities Between WSA-ENLIL+Cone Model and MAVEN in Situ Observations From November 2014 to March 2016
Baker, D. N.; Halekas, J. S.; Lee, C. O. +4 more
Normal solar wind flows and intense solar transient events interact directly with the upper Martian atmosphere due to the absence of an intrinsic global planetary magnetic field. Since the launch of the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission, there are now new means to directly observe solar wind parameters at the planet's orbital …
The onset of convective coupling and freezing in the white dwarfs of 47 Tucanae
Caiazzo, Ilaria; Heyl, Jeremy; Richer, Harvey +3 more
Using images from the Hubble Space Telescope Advanced Camera for Surveys, we measure the rate of cooling of white dwarfs in the globular cluster 47 Tucanae and compare it to modelled cooling curves. We examine the effects of the outer convective envelope reaching the nearly isothermal degenerate core and the release of latent heat during core crys…
Collisionless Boltzmann equation approach for the study of stellar discs within barred galaxies
Bienaymé, Olivier
We have studied the kinematics of stellar disc populations within the solar neighbourhood in order to find the imprints of the Galactic bar. We carried out the analysis by developing a numerical resolution of the 2D2V (two-dimensional in the physical space, 2D, and two-dimensional in the velocity motion, 2V) collisionless Boltzmann equation and mo…
General circular velocity relation of a test particle in a 3D gravitational potential: application to the rotation curves analysis and total mass determination of UGC 8490 and UGC 9753
Rosado, M.; Gabbasov, R.; Repetto, P. +1 more
In this paper, we derive a novel circular velocity relation for a test particle in a 3D gravitational potential applicable to every system of curvilinear coordinates, suitable to be reduced to orthogonal form. As an illustration of the potentiality of the determined circular velocity expression, we perform the rotation curves analysis of UGC 8490 …
Determination of mass and bulk density of asteroid (21) Lutetia using Rosetta radio tracking data
YANG, Xuan; YAN, JianGuo; YE, Mao +2 more