Search Publications
High precision comet trajectory estimates: The Mars flyby of C/2013 A1 (Siding Spring)
Micheli, M.; Farnocchia, D.; Delamere, W. A. +6 more
The Mars flyby of C/2013 A1 (Siding Spring) represented a unique opportunity for imaging a long-period comet and resolving its nucleus and rotation state. Because of the small encounter distance and the high relative velocity, the goal of successfully observing C/2013 A1 from the Mars orbiting spacecraft posed strict accuracy requirements on the c…
Spectroscopic Orbits for 15 Late-type Stars
Abt, Helmut A.; Fekel, Francis C.; Willmarth, Daryl W. +1 more
Spectroscopic orbital elements are determined for 15 stars with periods from 8 to 6528 days with six orbits computed for the first time. Improved astrometric orbits are computed for two stars and one new orbit is derived. Visual orbits were previously determined for four stars, four stars are members of multiple systems, and five stars have Hippar…
Ultra-Low-Frequency Waves at Venus and Mars
Dubinin, E.; Fraenz, M.
Mars and Venus have no global magnetic field. The solar wind interacts directly with their ionospheres and atmospheres, inducing magnetospheres by a pileup of the interplanetary magnetic field. The first measurements of the ultra-low-frequency activity on Mars were made by the Phobos-2 spacecraft. This chapter investigates the wave observations re…
The Molecular Baryon Cycle of M82
Chisholm, John; Matsushita, Satoki
Baryons cycle into galaxies from the intergalactic medium and are converted into stars; a fraction of the baryons are ejected out of galaxies by stellar feedback. Here we present new high-resolution (3.″9 68 pc) 12CO(2-1) and 12CO(3-2) images that probe these three stages of the baryon cycle in the nearby starburst M82. We co…
Lithospheric flexure and gravity spreading of Olympus Mons volcano, Mars
Williams, D. A.; Platz, T.; Dumke, A. +5 more
The structural architecture of large volcanoes is governed substantially by gravity-driven deformation that is manifest as distinct processes such as basement flexure or volcanic spreading. Temporal effects and the mutual interplay of these processes have been investigated only to a limited extent, and so we present novel numerical models of the t…
Disk-resolved photometry of Vesta and Lutetia and comparison with other asteroids
Longobardo, Andrea; Palomba, Ernesto; De Sanctis, Maria Cristina +7 more
Photometry of asteroids gives fundamental information about their spectral and physical properties. The aim of this work is two-fold: (1) to calculate phase functions of Vesta and Lutetia in the visible spectral range; and (2) to compare photometric properties of all the asteroids visited by space missions, as inferred from disk-resolved photometr…
Particle dynamics in a non-flaring solar active region model
Parnell, C. E.; Neukirch, T.; Threlfall, J. +1 more
Aims: The aim of this work is to investigate and characterise particle behaviour in an (observationally-driven) 3D magnetohydrodynamic (MHD) model of the solar atmosphere above a slowly evolving, non-flaring active region.
Methods: We use a relativistic guiding-centre particle code to investigate the behaviour of selected particle orbits…
Observations of high-plasma density region in the inner coma of 67P/Churyumov-Gerasimenko during early activity
Edberg, N. J. T.; Simon Wedlund, C.; Eriksson, A. I. +5 more
In 2014 September, as Rosetta transitioned to close bound orbits at 30 km from comet 67P/Churyumov-Gerasimenko, the Rosetta Plasma Consortium Langmuir probe (RPC-LAP) data showed large systematic fluctuations in both the spacecraft potential and the collected currents. We analyse the potential bias sweeps from RPC-LAP, from which we extract three …
Pulsations of the polar cusp aurora at Saturn
Krupp, N.; Roussos, E.; Mitchell, D. G. +4 more
The magnetospheric cusp is a region connecting the interplanetary environment to the ionosphere and enabling solar wind particles to reach the ionosphere. We report the detection of several isolated high-latitude auroral emissions with the Ultraviolet Imaging Spectrograph of the Cassini spacecraft. We suggest that these auroral spots, located in t…
Thermal properties of Rhea's poles: Evidence for a meter-deep unconsolidated subsurface layer
Spencer, J. R.; Howett, C. J. A.; Segura, M. +2 more
Cassini's Composite Infrared Spectrometer (CIRS) observed both of Rhea's polar regions during a close (2000 km) flyby on 9th March 2013 during orbit 183. Rhea's southern pole was again observed during a more distant (51,000 km) flyby on 10th February 2015 during orbit 212. The results show Rhea's southern winter pole is one of the coldest places d…