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Clastic patterned ground in Lomonosov crater, Mars: examining fracture controlled formation mechanisms
Balme, Matthew R.; Patel, Manish R.; Hagermann, Axel +1 more
The area surrounding Lomonosov crater on Mars has a high density of seemingly organised boulder patterns. These form seemingly sorted polygons and stripes within kilometre scale blockfields, patches of boulder strewn ground which are common across the Martian high latitudes. Several hypotheses have been suggested to explain the formation of clasti…
The reflectivity of Mars at 1064 nm: Derivation from Mars Orbiter Laser Altimeter data and application to climatology and meteorology
Heavens, N. G.
The Mars Orbiter Laser Altimeter (MOLA) on board Mars Global Surveyor (MGS) made > 108 measurements of the reflectivity of Mars at 1064 nm (R1064) by both active sounding and passive radiometry. Past studies of R1064 neglected the effects of atmospheric opacity and viewing geometry on both active and passive mea…
Discovery of a 150 day period in the Venus condensational clouds
Tsang, Constantine C. C.; McGouldrick, Kevin
We have analyzed the long-term regional and global variation of emitted radiance in 1.74 µ m and 2.30 µ m near infrared spectral windows in the Venus atmosphere using the medium resolution, infrared channel of the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS-M-IR) on the Venus Express spacecraft. We find a periodic variati…
Search for HBr and bromine photochemistry on Venus
Krasnopolsky, Vladimir A.; Belyaev, Denis A.
HBr (1-0) R2 2605.8/6.2 cm-1, the strongest line of the strongest band of HBr, was observed when searching for this species on Venus. The observation was conducted using the NASA IRTF and a high-resolution long-slit spectrograph CSHELL with resolving power of 4 × 104. 101 spectra of Venus were analyzed, and the retrieved HBr …
Saturn's rings and associated ring plasma cavity: Evidence for slow ring erosion
Gurnett, D. A.; Persoon, A. M.; Kurth, W. S. +2 more
We re-examine the radio and plasma wave observations obtained during the Cassini Saturn orbit insertion period, as the spacecraft flew over the northern ring surface into a radial distance of 1.3 Rs (over the C-ring). Voyager era studies suggest the rings are a source of micro-meteoroid generated plasma and dust, with theorized peak imp…
Wind shear and turbulence on Titan: Huygens analysis
Lorenz, Ralph D.
Wind shear measured by Doppler tracking of the Huygens probe is evaluated, and found to be within the range anticipated by pre-flight assessments (namely less than two times the Brunt-Väisälä frequency). The strongest large-scale shear encountered was ∼5 m/s/km, a level associated with 'Light' turbulence in terrestrial aviation. Near-surface winds…
Study of ice-related flow features around Tanaica Montes, Mars: Implications for late amazonian debris-covered glaciation
Vijayan, S.; Sinha, Rishitosh K.; Bharti, Rajiv R.
Lobate debris aprons (LDA) and lineated valley fill (LVF) have been broadly recognized in the mid-latitudes of Mars and their subsequent analyses using data from the SHAllow RADar (SHARAD) instrument has suggested evidence for contemporary ice preserved beneath these features. In this study, we conduct detailed characterization of newly identified…
Long-lived volcanism within Argyre basin, Mars
Lopes, Rosaly M. C.; Flahaut, Jessica; Buczkowski, Debra L. +6 more
The Argyre basin, one of the largest impact structures on Mars with a diameter >1200 km, formed in the Early Noachian ∼3.93 Ga. The basin has collected volatiles and other material through time, and experienced partial infilling with water evident from stratigraphic sequences, crater statistics, topography, and geomorphology. Although volcanism…
General circulation of Venus from a long-term synoptic study of tropospheric CO by Venus Express/VIRTIS
Tsang, Constantine C. C.; McGouldrick, Kevin
The understanding of spatial and temporal variations in tropospheric abundances of the trace gas carbon monoxide (CO) is key to understanding the deep atmospheric circulation on Venus. CO is entrained in the global circulation, as well as being key ingredients in the multi-reaction chemical cycle that creates and destroys the sulfuric acid that is…
Upper limit of helium-4 in the sunlit lunar exosphere during magnetotail passage under low solar wind condition: Result from CHACE aboard MIP in Chandrayaan-1
Bhardwaj, Anil; Sridharan, R.; Dhanya, M. B. +3 more
The outcome of efforts to detect He-4 in the sunlit lunar exosphere as evinced by the CHACE mass spectrometer aboard the Moon Impact Probe in Chandrayaan-1 is reported. The in situ observations by CHACE were carried out in the lunar dayside, covering a broad range of lunar latitudes, when the Moon was on the verge of exiting the Earth's magnetotai…