Publications
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Results of the Imager for Mars Pathfinder windsock experiment
The Imager for Mars Pathfinder (IMP) windsock experiment measured wind speeds at three heights within 1.2 m of the Martian surface during Pathfinder landed operations. These wind data allowed direct measurement of near-surface wind profiles on Mars for the first time, including determination of aerodynamic roughness length and wind friction speeds. Winds were light during periods of windsock imagi
Authors
Robert Sullivan, Ronald Greeley, Michael Kraft, Gregory Wilson, Matthew P. Golombek, Kenneth E. Herkenhoff, James Murphy, Peter Smith
Topography and Stratigraphy of the Northern Martian Polar Layered Deposits Using Photoclinometry, Stereogrammetry, and MOLA Altimetry
We present two photoclinometric profiles across a trough in the martian northern polar layered terrain. Complications caused by albedo variations were avoided by using an early springtime Viking image with a thin cover of seasonal CO2 frost. The topographic profiles were constrained with stereogrammetric elevations derived from summertime Viking images of the same region.We find that the photoclin
Authors
Lori K. Fenton, Kenneth E. Herkenhoff
Variability of Mars' North Polar water ice cap: I. Analysis of Mariner 9 and Viking Orbiter imaging data
Previous studies interpreted differences in ice coverage between Mariner 9 and Viking Orbiter observations of Mars' north residual polar cap as evidence of interannual variability of ice deposition on the cap. However, these investigators did not consider the possibility that there could be significant changes in the ice coverage within the northern residual cap over the course of the summer seaso
Authors
Deborah S. Bass, Kenneth E. Herkenhoff, David A. Paige
Surface properties of Mars' polar layered deposits and polar landing sites
On December 3, 1999, the Mars Polar Lander and Mars Microprobes will land on the planet's south polar layered deposits near (76°S, 195°W) and conduct the first in situ studies of the planet's polar regions. The scientific goals of these missions address several poorly understood and globally significant issues, such as polar meteorology, the composition and volatile content of the layered deposits
Authors
Ashwin R. Vasavada, Jean-Pierre Williams, David A. Paige, Kenneth E. Herkenhoff, Nathan T. Bridges, Ronald Greeley, Bruce C. Murray, Deborah S. Bass, Karen S. McBride
The state and future of Mars polar science and exploration
As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of ∼106 km2 and total as much as 3–4 km thick. From the scarcity of superposed craters on their surface, these layered deposits are thought to be comparatively young—preserving a record of the seasonal and climatic cycling of atmospheric CO2, H2O, and dust
Authors
S.M. Clifford, D. Crisp, D.A. Fisher, Kenneth E. Herkenhoff, S.E. Smrekar, P. C. Thomas, D. D. Wynn-Williams, R.W. Zurek, J.R. Barnes, B.G. Bills, E.W. Blake, W. M. Calvin, J.M. Cameron, M. H. Carr, P. R. Christensen, B. C. Clark, G.D. Clow, J.A. Cutts, D. Dahl-Jensen, W. B. Durham, F. P. Fanale, J.D. Farmer, F. Forget, K. Gotto-Azuma, R. Grard, R.M. Haberle, W. Harrison, R. Harvey, A.D. Howard, A.P. Ingersoll, P.B. James, J.S. Kargel, H. H. Kieffer, J. Larsen, K. Lepper, M. C. Malin, D. J. McCleese, B. Murray, J.F. Nye, D. A. Paige, S.R. Platt, J.J. Plaut, N. Reeh, J.W. Rice, D.E. Smith, C. R. Stoker, K. L. Tanaka, E. Mosley-Thompson, T. Thorsteinsson, S.E. Wood, A. Zent, M.T. Zuber, H.J. Zwally
Surface ages and resurfacing rates of the Polar Layered Deposits on Mars
Interpretation of the polar stratigraphy of Mars in terms of global climate changes is complicated by the significant difference in surface ages between the north and south polar layered terrains inferred from crater statistics. We have reassessed the cratering record in both polar regions using Viking Orbiter and Mariner 9 images. No craters have been found in the north polar layered terrain, but
Authors
Kenneth E. Herkenhoff, Jeffrey J. Plaut
Mars south polar spring and summer behavior observed by TES: seasonal cap evolution controlled by frost grain size
Thermal Emission Spectrometer (TES) observations of the recession phase of Mars' south polar cap are used to quantitatively map this recession in both thermal and visual appearance. Geographically nonuniform behavior interior to the cap is characterized by defining several small regions which exemplify the range of behavior. For most of the cap, while temperatures remain near the CO2 frost point,
Authors
Hugh H. Kieffer, Timothy N. Titus, Kevin F. Mullins, Phillip R. Christensen
Sinus Meridiani: uncontrolled Mars Global Surveyor (MGS) Mars Orbital Camera (MOC): digital context photomosaic (250 megapixel resolution)
These images were processed from a raw format using Integrated Software for Images and Spectrometers (ISIS) to perform radiometric corrections and projection. All the images were projected in sinusoidal using a center longitude of 0 degrees. There are two versions of the mosaic, one unfiltered (sinusmos.tif), and one produced with all images processed through a box filter with an averaged pixel to
Authors
Eric Noreen
Central Valles Marineris: uncontrolled Mars Global Surveyor (MGS) Mars Orbital Camera (MOC) digital context photomosaic (250 megapixel resolution)
These images were processed from a raw format using Integrated Software for Images and Spectrometers (ISIS) to perform radiometric corrections and projection. All the images were projected in sinusoidal using a center longitude of 70 degrees. There are two versions of the mosaic, one unfiltered (vallesmos.tif), and one produced with all images processed through a box filter with an averaged pixel
Authors
Eric Noreen
Does Europa have a subsurface ocean? Evaluation of the geological evidence
It has been proposed that Jupiter's satellite Europa currently possesses a global subsurface ocean of liquid water. Galileo gravity data verify that the satellite is differentiated into an outer H2O layer about 100 km thick but cannot determine the current physical state of this layer (liquid or solid). Here we summarize the geological evidence regarding an extant subsurface ocean, concentrating o
Authors
Robert T. Pappalardo, Michael J.S. Belton, H.H. Breneman, M. H. Carr, Clark R. Chapman, G.C. Collins, T. Denk, S. Fagents, Paul E. Geissler, B. Giese, R. Greeley, R. Greenberg, J.W. Head, P. Helfenstein, G. Hoppa, S.D. Kadel, K.P. Klaasen, James E. Klemaszewski, K.P. Magee, Alfred S. McEwen, J.M. Moore, W.B. Moore, G. Neukum, C.B. Phillips, L.M. Prockter, G. Schubert, D.A. Senske, R.J. Sullivan, B.R. Tufts, E. P. Turtle, Robert Wagner, K.K. Williams
Observations of Phobos, Deimos, and bright stars with the Imager for Mars Pathfinder
The Imager for Mars Pathfinder (IMP) was used to observe several objects during the Martian night. The satellites, Phobos and Deimos, were observed on two occasions each, through the IMP geological filters covering the wavelength range 440 nm to 1 μm. The observations were converted to geometric albedo using triaxial ellipsoid models of the satellites and phase functions derived from Viking Orbite
Authors
Nick Thomas, D.T. Britt, Kenneth E. Herkenhoff, Scott L. Murchie, B. Semenov, H.U. Keller, P. H. Smith
Mars Pathfinder spectral measurements of Phobos and Deimos: Comparison with previous data
The Imager for Mars Pathfinder (IMP) acquired four spectra of parts of the sub‐Mars hemispheres of Phobos and Deimos. The measured region of Phobos is expected to be a mixture of the two spectral units identified on that satellite from Phobos 2 data, and the IMP spectra of Phobos are intermediate to the two units as expected. The derived geometric albedo is consistent with the value for that part
Authors
Scott L. Murchie, Nick Thomas, Daniel Britt, Kenneth E. Herkenhoff, James F. Bell