Vishnu Reddy

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We report on a preliminary global geologic map of Vesta, based on data from the Dawn spacecraft’s HighAltitude Mapping Orbit (HAMO) and informed by Low-Altitude Mapping Orbit (LAMO) data. This map is part of an iterative mapping effort; the geologic map has been refined with each improvement in resolution. Vesta has a heavily-cratered surface, with large(More)
Using Dawn's Gamma Ray and Neutron Detector, we tested models of Vesta's evolution based on studies of howardite, eucrite, and diogenite (HED) meteorites. Global Fe/O and Fe/Si ratios are consistent with HED compositions. Neutron measurements confirm that a thick, diogenitic lower crust is exposed in the Rheasilvia basin, which is consistent with global(More)
Multispectral images (0.44 to 0.98 μm) of asteroid (4) Vesta obtained by the Dawn Framing Cameras reveal global color variations that uncover and help understand the north-south hemispherical dichotomy. The signature of deep lithologies excavated during the formation of the Rheasilvia basin on the south pole has been preserved on the surface. Color(More)
A combination tapered fiber-optic biosensor (CTFOB) dip probe for rapid and cost-effective quantification of proteins in serum samples has been developed. This device relies on diode laser excitation and a charged-coupled device spectrometer and functions on a technique of sandwich immunoassay. As a proof of principle, this technique was applied in a(More)
http://dx.doi.org/10.1016/j.icarus.2014.03.035 0019-1035/ 2014 Published by Elsevier Inc. ⇑ Corresponding author. E-mail address: debra.buczkowski@jhuapl.edu (D.L. Buczkowski). D.L. Buczkowski a,⇑, D.Y. Wyrick , M. Toplis , R.A. Yingst , D.A. Williams , W.B. Garry , S. Mest , T. Kneissl , J.E.C. Scully , A. Nathues , M.C. De Sanctis , L. LeCorre , V. Reddy(More)
[1] The Framing Camera (FC) on the Dawn spacecraft provided the first view of 4 Vesta at sufficiently high spatial resolution to enable a detailed correlation of the asteroid’s spectral properties with geologic features and with the vestoid (V-type) asteroids and the Howardite-Eucrite-Diogenite (HED) class of meteorites, both of which are believed to(More)
Exposure to ion and micrometeoroid bombardment in the space environment causes physical and chemical changes in the surface of an airless planetary body. These changes, called space weathering, can strongly influence a surface’s optical characteristics, and hence complicate interpretation of composition from reflectance spectroscopy. Prior work using data(More)
Olivine-rich asteroids appear to be common in the main asteroid belt as well as present in the near-Earth asteroid population. There are a number of meteorite classes that are dominated by olivine ± metal. To determine whether relationships exist between these asteroids and meteorites, we spectrally characterized a number of olivine + meteoriticmetal powder(More)
In anticipation of theDawnMission to 4Vesta,we conducted a ground-based campaign of Bessel BVRI filter photometry of five V-type near-Earth asteroids over a wide range of solar phase angles. We also obtained medium-resolution optical spectroscopy (0.38 lm < k < 0.92 lm; R 500) of sixteen near-Earth andmainbelt V-type asteroids in order to investigate their(More)