Publications
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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
Overview of the Mars Pathfinder Mission: Launch through landing, surface operations, data sets, and science results
Mars Pathfinder successfully landed at Ares Vallis on July 4, 1997, deployed and navigated a small rover about 100 m clockwise around the lander, and collected data from three science instruments and ten technology experiments. The mission operated for three months and returned 2.3 Gbits of data, including over 16,500 lander and 550 rover images, 16 chemical analyses of rocks and soil, and 8.5 mil
Authors
M. P. Golombek, R. C. Anderson, J.R. Barnes, J. F. III Bell, N. T. Bridges, D.T. Britt, J. Brückner, R. A. Cook, D. Crisp, J.A. Crisp, T. Economou, W. M. Folkner, R. Greeley, R.M. Haberle, R.B. Hargraves, J.A. Harris, A. F. C. Haldemann, Kenneth E. Herkenhoff, S.F. Hviid, R. Jaumann, J. R. Johnson, P. H. Kallemeyn, H.U. Keller, Randolph L. Kirk, J. M. Knudsen, S. Larsen, M. T. Lemmon, M.B. Madsen, J.A. Magalhães, J.N. Maki, M.C. Malin, R. M. Manning, J. Matijevic, H.Y. McSween, H. J. Moore, S.L. Murchie, J.R. Murphy, T. J. Parker, R. Rieder, T.P. Rivellini, J. T. Schofield, A. Seiff, R.B. Singer, P. H. Smith, Laurence A. Soderblom, D.A. Spencer, C. R. Stoker, R. Sullivan, N. Thomas, S.W. Thurman, M.G. Tomasko, R. M. Vaughan, H. Wänke, A. W. Ward, G.R. Wilson
Digital photogrammetric analysis of the IMP camera images: Mapping the Mars Pathfinder landing site in three dimensions
This paper describes our photogrammetric analysis of the Imager for Mars Pathfinder data, part of a broader program of mapping the Mars Pathfinder landing site in support of geoscience investigations. This analysis, carried out primarily with a commercial digital photogrammetric system, supported by our in‐house Integrated Software for Imagers and Spectrometers (ISIS), consists of three steps: (1)
Authors
Randolph L. Kirk, Elpitha Howington-Kraus, Trent M. Hare, E. Dorrer, D. Cook, Kris J. Becker, K. Thompson, B. Redding, J. Blue, D. Galuszka, E.M. Lee, Lisa R. Gaddis, J. R. Johnson, Laurence A. Soderblom, A. W. Ward, P. H. Smith, D.T. Britt
Aeolian features and processes at the Mars Pathfinder landing site
The Mars Pathfinder landing site contains abundant features attributed to aeolian, or wind, processes. These include wind tails, drift deposits, duneforms of various types, ripplelike features, and ventifacts (the first clearly seen on Mars). Many of these features are consistant with formation involving sand-size particles. Although some features, such as dunes, could develop from saltating sand-
Authors
Ronald Greeley, Michael Kraft, Robert Sullivan, Gregory Wilson, Nathan Bridges, Kenneth E. Herkenhoff, Ruslan O. Kuzmin, Michael Malin, Wes Ward
Ventifacts at the Pathfinder landing site
About half of the rocks at the Mars Pathfinder Ares Vallis landing site appear to be ventifacts, rocks abraded by windborne particles. Comparable resolution images taken by the Imager for Mars Pathfinder (IMP) camera and the Viking landers show that ventifacts are more abundant at the Pathfinder site. The ventifacts occur in several forms, including rocks with faceted edges, finger‐like projection
Authors
N.T. Bridges, R. Greeley, A. F. C. Haldemann, Kenneth E. Herkenhoff, M. Kraft, T. J. Parker, A. W. Ward
Preliminary results on photometric properties of materials at the Sagan Memorial Station, Mars
Reflectance measurements of selected rocks and soils over a wide range of illumination geometries obtained by the Imager for Mars Pathfinder (IMP) camera provide constraints on interpretations of the physical and mineralogical nature of geologic materials at the landing site. The data sets consist of (1) three small “photometric spot” subframed scenes, covering phase angles from 20° to 150°; (2) t
Authors
Jeffrey R. Johnson, Randolph L. Kirk, Laurence A. Soderblom, Lisa R. Gaddis, Robert J. Reid, Daniel T. Britt, Peter Smith, Mark T. Lemmon, Nicolas Thomas, James F. Bell, Nathan T. Bridges, Robert Anderson, Kenneth E. Herkenhoff, Justin N. Maki, Scott L. Murchie, Andreas Dummel, Ralf Jaumann, Frank Trauthan, Gabriele Arnold