Kenneth Edward Herkenhoff, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 145
Bedrock formation at Meridiani Planum
The Mars Exploration Rover Opportunity discovered sulphate-rich sedimentary rocks at Meridiani Planum on Mars, which are interpreted by McCollom and Hynek as altered volcanic rocks. However, their conclusions are derived from an incorrect representation of our depositional model, which is upheld by more recent Rover data. We contend that all the available data still support an aeolian and aqueous
Authors
S. W. Squyres, O. Aharonson, R. E. Arvidson, J.F. Bell, P. R. Christensen, B. C. Clark, J.A. Crisp, W. Farrand, T. Glotch, M.P. Golombek, J. Grant, J. Grotzinger, Kenneth E. Herkenhoff, J. R. Johnson, B.L. Jolliff, A.H. Knoll, S. M. McLennan, H.Y. McSween, Johnnie N. Moore, J. W. Rice, N. Tosca
Alkaline volcanic rocks from the Columbia Hills, Gusev crater, Mars
Irvine, Backstay, and Wishstone are the type specimens for three classes of fine-grained or fragmental, relatively unaltered rocks with distinctive thermal emission spectra, found as float on the flanks of the Columbia Hills. Chemical analyses indicate that these rocks are mildly alkaline basalt, trachybasalt, and tephrite, respectively. Their mineralogy consists of Na- and K-rich feldspar(s), low
Authors
H.Y. McSween, S. W. Ruff, R.V. Morris, J.F. Bell, Kenneth E. Herkenhoff, Ralf Gellert, K.R. Stockstill, L.L. Tornabene, S. W. Squyres, J.A. Crisp, P. R. Christensen, T.J. McCoy, D. W. Mittlefehldt, M. Schmidt
Two years at Meridiani Planum: Results from the Opportunity Rover
The Mars Exploration Rover Opportunity has spent more than 2 years exploring Meridiani Planum, traveling ∼8 kilometers and detecting features that reveal ancient environmental conditions. These include well-developed festoon (trough) cross-lamination formed in flowing liquid water, strata with smaller and more abundant hematite-rich concretions than those seen previously, possible relict “hopper c
Authors
S. W. Squyres, A.H. Knoll, R. E. Arvidson, B. C. Clark, J.P. Grotzinger, B.L. Jolliff, S. M. McLennan, N. Tosca, J.F. Bell, W. M. Calvin, W. H. Farrand, T.D. Glotch, M.P. Golombek, Kenneth E. Herkenhoff, J. R. Johnson, G. Klingelhofer, H.Y. McSween, A. S. Yen
Stratigraphy and sedimentology of a dry to wet eolian depositional system, Burns formation, Meridiani Planum, Mars
Outcrop exposures of sedimentary rocks at the Opportunity landing site (Meridiani Planum) form a set of genetically related strata defined here informally as the Burns formation. This formation can be subdivided into lower, middle, and upper units which, respectively, represent eolian dune, eolian sand sheet, and mixed eolian sand sheet and interdune facies associations. Collectively, these three
Authors
J. P. Grotzinger, R. E. Arvidson, J. F. III Bell, W. Calvin, B. C. Clark, D.A. Fike, M. Golombek, R. Greeley, A. Haldemann, Kenneth E. Herkenhoff, B. L. Jolliff, A. H. Knoll, M. Malin, S. M. McLennan, T. Parker, Laurence A. Soderblom, J. N. Sohl-Dickstein, S. W. Squyres, N.J. Tosca, W.A. Watters
Aeolian processes at the Mars Exploration Rover Meridiani Planum landing site
The martian surface is a natural laboratory for testing our understanding of the physics of aeolian (wind-related) processes in an environment different from that of Earth. Martian surface markings and atmospheric opacity are time-variable, indicating that fine particles at the surface are mobilized regularly by wind. Regolith (unconsolidated surface material) at the Mars Exploration Rover Opportu
Authors
R. Sullivan, D. Banfield, J.F. Bell, W. Calvin, D. Fike, M. Golombek, R. Greeley, J. Grotzinger, Kenneth E. Herkenhoff, D. Jerolmack, M. Malin, D. Ming, Laurence A. Soderblom, S. W. Squyres, S. Thompson, W.A. Watters, C.M. Weitz, A. Yen
An integrated view of the chemistry and mineralogy of martian soils
The mineralogical and elemental compositions of the martian soil are indicators of chemical and physical weathering processes. Using data from the Mars Exploration Rovers, we show that bright dust deposits on opposite sides of the planet are part of a global unit and not dominated by the composition of local rocks. Dark soil deposits at both sites have similar basaltic mineralogies, and could refl
Authors
A. S. Yen, Ralf Gellert, C. Schroder, R.V. Morris, J.F. Bell, A.T. Knudson, B. C. Clark, D. W. Ming, J.A. Crisp, R. E. Arvidson, D. Blaney, J. Brückner, P. R. Christensen, D.J. DesMarais, P.A. De Souza, T.E. Economou, A. Ghosh, B.C. Hahn, Kenneth E. Herkenhoff, L.A. Haskin, J.A. Hurowitz, B.L. Joliff, J. R. Johnson, G. Klingelhofer, M.B. Madsen, S. M. McLennan, H.Y. McSween, L. Richter, R. Rieder, D. Rodionov, Laurence A. Soderblom, S. W. Squyres, N.J. Tosca, A. Wang, M. Wyatt, J. Zipfel
Water alteration of rocks and soils on Mars at the Spirit rover site in Gusev crater
Gusev crater was selected as the landing site for the Spirit rover because of the possibility that it once held a lake. Thus one of the rover's tasks was to search for evidence of lake sediments. However, the plains at the landing site were found to be covered by a regolith composed of olivine-rich basaltic rock and wind-blown 'global' dust. The analyses of three rock interiors exposed by the rock
Authors
L.A. Haskin, A. Wang, B.L. Jolliff, H.Y. McSween, B. C. Clark, D.J. Des Marais, S. M. McLennan, N.J. Tosca, J.A. Hurowitz, J.D. Farmer, A. Yen, S. W. Squyres, R. E. Arvidson, G. Klingelhofer, C. Schroder, P.A. De Souza, D. W. Ming, Ralf Gellert, J. Zipfel, J. Brückner, J.F. Bell, Kenneth E. Herkenhoff, P. R. Christensen, S. Ruff, D. Blaney, S. Gorevan, N.A. Cabrol, L. Crumpler, J. Grant, L. Soderblom
Mars exploration rover geologic traverse by the spirit rover in the plains of Gusev crater, Mars
The Spirit rover completed a 2.5 km traverse across gently sloping plains on the floor of Gusev crater from its location on the outer rim of Bonneville crater to the lower slopes of the Columbia Hills, Mars. Using the Athena suite of instruments in a transect approach, a systematic series of overlapping panoramic mosaics, remote sensing observations, surface analyses, and trenching operations docu
Authors
L.S. Crumpler, S. W. Squyres, R. E. Arvidson, J.F. Bell, D. Blaney, N.A. Cabrol, P. R. Christensen, D.J. DesMarais, J.D. Farmer, R. Fergason, M.P. Golombek, F.D. Grant, J. A. Grant, R. Greeley, B. Hahn, Kenneth E. Herkenhoff, J.A. Hurowitz, A.T. Knudson, G. A. Landis, R. Li, J. Maki, H.Y. McSween, D. W. Ming, J.E. Moersch, M.C. Payne, J.W. Rice, L. Richter, S. W. Ruff, M. Sims, S.D. Thompson, N. Tosca, A. Wang, P. Whelley, S.P. Wright, M.B. Wyatt
Provenance and diagenesis of the evaporite-bearing Burns formation, Meridiani Planum, Mars
Impure reworked evaporitic sandstones, preserved on Meridiani Planum, Mars, are mixtures of roughly equal amounts of altered siliciclastic debris, of basaltic provenance (40 ± 10% by mass), and chemical constituents, dominated by evaporitic minerals (jarosite, Mg-, Ca-sulfates ± chlorides ± Fe-, Na-sulfates), hematite and possibly secondary silica (60 ± 10%). These chemical constituents and their
Authors
S. M. McLennan, J.F. Bell, W. M. Calvin, P. R. Christensen, B. C. Clark, P.A. de Souza, J. Farmer, W. H. Farrand, D.A. Fike, Ralf Gellert, A. Ghosh, T.D. Glotch, J.P. Grotzinger, B. Hahn, Kenneth E. Herkenhoff, J.A. Hurowitz, J. R. Johnson, S.S. Johnson, B. Jolliff, G. Klingelhofer, A.H. Knoll, Z. Learner, M. C. Malin, H.Y. McSween, J. Pocock, S. W. Ruff, Laurence A. Soderblom, S. W. Squyres, N.J. Tosca, W.A. Watters, M.B. Wyatt, A. Yen
Evidence from Opportunity’s Microscopic Imager for water on Meridiani Planum
The Microscopic Imager on the Opportunity rover analyzed textures of soils and rocks at Meridiani Planum at a scale of 31 micrometers per pixel. The uppermost millimeter of some soils is weakly cemented, whereas other soils show little evidence of cohesion. Rock outcrops are laminated on a millimeter scale; image mosaics of cross-stratification suggest that some sediments were deposited by flowing
Authors
Kenneth E. Herkenhoff, S. W. Squyres, R. Arvidson, D.S. Bass, J. F. III Bell, P. Bertelsen, B. L. Ehlmann, W. Farrand, Lisa R. Gaddis, R. Greeley, J. Grotzinger, A. G. Hayes, S.F. Hviid, J. R. Johnson, B. Jolliff, K.M. Kinch, A. H. Knoll, M.B. Madsen, J.N. Maki, S. M. McLennan, H.Y. McSween, D. W. Ming, J. W. Rice, L. Richter, M. Sims, P. H. Smith, Laurence A. Soderblom, Nicole Spanovich, R. Sullivan, S. Thompson, T. Wdowiak, C. Weitz, P. Whelley
Textures of the soils and rocks at Gusev Crater from Spirit’s Microscopic Imager
The Microscopic Imager on the Spirit rover analyzed the textures of the soil and rocks at Gusev crater on Mars at a resolution of 100 micrometers. Weakly bound agglomerates of dust are present in the soil near the Columbia Memorial Station. Some of the brushed or abraded rock surfaces show igneous textures and evidence for alteration rinds, coatings, and veins consistent with secondary mineralizat
Authors
Kenneth E. Herkenhoff, S. W. Squyres, R. Arvidson, D.S. Bass, J. F. III Bell, P. Bertelsen, N.A. Cabrol, Lisa R. Gaddis, A. G. Hayes, S.F. Hviid, J. R. Johnson, K.M. Kinch, M.B. Madsen, J.N. Maki, S. M. McLennan, H.Y. McSween, J. W. Rice, M. Sims, P. H. Smith, Laurence A. Soderblom, Nicole Spanovich, R. Sullivan, A. Wang
Magnetic properties experiments on the Mars Exploration Rover Spirit at Gusev Crater
The magnetic properties experiments are designed to help identify the magnetic minerals in the dust and rocks on Mars—and to determine whether liquid water was involved in the formation and alteration of these magnetic minerals. Almost all of the dust particles suspended in the martian atmosphere must contain ferrimagnetic minerals (such as maghemite or magnetite) in an amount of ∼2% by weight. Th
Authors
P. Bertelsen, W. Goetz, M.B. Madsen, K.M. Kinch, S.F. Hviid, J. M. Knudsen, H.P. Gunnlaugsson, J. Merrison, P. Nørnberg, S. W. Squyres, J. F. III Bell, Kenneth E. Herkenhoff, S. Gorevan, A. S. Yen, T. Myrick, G. Klingelhoefer, R. Rieder, R. Gellert
Science and Products
Filter Total Items: 145
Bedrock formation at Meridiani Planum
The Mars Exploration Rover Opportunity discovered sulphate-rich sedimentary rocks at Meridiani Planum on Mars, which are interpreted by McCollom and Hynek as altered volcanic rocks. However, their conclusions are derived from an incorrect representation of our depositional model, which is upheld by more recent Rover data. We contend that all the available data still support an aeolian and aqueous
Authors
S. W. Squyres, O. Aharonson, R. E. Arvidson, J.F. Bell, P. R. Christensen, B. C. Clark, J.A. Crisp, W. Farrand, T. Glotch, M.P. Golombek, J. Grant, J. Grotzinger, Kenneth E. Herkenhoff, J. R. Johnson, B.L. Jolliff, A.H. Knoll, S. M. McLennan, H.Y. McSween, Johnnie N. Moore, J. W. Rice, N. Tosca
Alkaline volcanic rocks from the Columbia Hills, Gusev crater, Mars
Irvine, Backstay, and Wishstone are the type specimens for three classes of fine-grained or fragmental, relatively unaltered rocks with distinctive thermal emission spectra, found as float on the flanks of the Columbia Hills. Chemical analyses indicate that these rocks are mildly alkaline basalt, trachybasalt, and tephrite, respectively. Their mineralogy consists of Na- and K-rich feldspar(s), low
Authors
H.Y. McSween, S. W. Ruff, R.V. Morris, J.F. Bell, Kenneth E. Herkenhoff, Ralf Gellert, K.R. Stockstill, L.L. Tornabene, S. W. Squyres, J.A. Crisp, P. R. Christensen, T.J. McCoy, D. W. Mittlefehldt, M. Schmidt
Two years at Meridiani Planum: Results from the Opportunity Rover
The Mars Exploration Rover Opportunity has spent more than 2 years exploring Meridiani Planum, traveling ∼8 kilometers and detecting features that reveal ancient environmental conditions. These include well-developed festoon (trough) cross-lamination formed in flowing liquid water, strata with smaller and more abundant hematite-rich concretions than those seen previously, possible relict “hopper c
Authors
S. W. Squyres, A.H. Knoll, R. E. Arvidson, B. C. Clark, J.P. Grotzinger, B.L. Jolliff, S. M. McLennan, N. Tosca, J.F. Bell, W. M. Calvin, W. H. Farrand, T.D. Glotch, M.P. Golombek, Kenneth E. Herkenhoff, J. R. Johnson, G. Klingelhofer, H.Y. McSween, A. S. Yen
Stratigraphy and sedimentology of a dry to wet eolian depositional system, Burns formation, Meridiani Planum, Mars
Outcrop exposures of sedimentary rocks at the Opportunity landing site (Meridiani Planum) form a set of genetically related strata defined here informally as the Burns formation. This formation can be subdivided into lower, middle, and upper units which, respectively, represent eolian dune, eolian sand sheet, and mixed eolian sand sheet and interdune facies associations. Collectively, these three
Authors
J. P. Grotzinger, R. E. Arvidson, J. F. III Bell, W. Calvin, B. C. Clark, D.A. Fike, M. Golombek, R. Greeley, A. Haldemann, Kenneth E. Herkenhoff, B. L. Jolliff, A. H. Knoll, M. Malin, S. M. McLennan, T. Parker, Laurence A. Soderblom, J. N. Sohl-Dickstein, S. W. Squyres, N.J. Tosca, W.A. Watters
Aeolian processes at the Mars Exploration Rover Meridiani Planum landing site
The martian surface is a natural laboratory for testing our understanding of the physics of aeolian (wind-related) processes in an environment different from that of Earth. Martian surface markings and atmospheric opacity are time-variable, indicating that fine particles at the surface are mobilized regularly by wind. Regolith (unconsolidated surface material) at the Mars Exploration Rover Opportu
Authors
R. Sullivan, D. Banfield, J.F. Bell, W. Calvin, D. Fike, M. Golombek, R. Greeley, J. Grotzinger, Kenneth E. Herkenhoff, D. Jerolmack, M. Malin, D. Ming, Laurence A. Soderblom, S. W. Squyres, S. Thompson, W.A. Watters, C.M. Weitz, A. Yen
An integrated view of the chemistry and mineralogy of martian soils
The mineralogical and elemental compositions of the martian soil are indicators of chemical and physical weathering processes. Using data from the Mars Exploration Rovers, we show that bright dust deposits on opposite sides of the planet are part of a global unit and not dominated by the composition of local rocks. Dark soil deposits at both sites have similar basaltic mineralogies, and could refl
Authors
A. S. Yen, Ralf Gellert, C. Schroder, R.V. Morris, J.F. Bell, A.T. Knudson, B. C. Clark, D. W. Ming, J.A. Crisp, R. E. Arvidson, D. Blaney, J. Brückner, P. R. Christensen, D.J. DesMarais, P.A. De Souza, T.E. Economou, A. Ghosh, B.C. Hahn, Kenneth E. Herkenhoff, L.A. Haskin, J.A. Hurowitz, B.L. Joliff, J. R. Johnson, G. Klingelhofer, M.B. Madsen, S. M. McLennan, H.Y. McSween, L. Richter, R. Rieder, D. Rodionov, Laurence A. Soderblom, S. W. Squyres, N.J. Tosca, A. Wang, M. Wyatt, J. Zipfel
Water alteration of rocks and soils on Mars at the Spirit rover site in Gusev crater
Gusev crater was selected as the landing site for the Spirit rover because of the possibility that it once held a lake. Thus one of the rover's tasks was to search for evidence of lake sediments. However, the plains at the landing site were found to be covered by a regolith composed of olivine-rich basaltic rock and wind-blown 'global' dust. The analyses of three rock interiors exposed by the rock
Authors
L.A. Haskin, A. Wang, B.L. Jolliff, H.Y. McSween, B. C. Clark, D.J. Des Marais, S. M. McLennan, N.J. Tosca, J.A. Hurowitz, J.D. Farmer, A. Yen, S. W. Squyres, R. E. Arvidson, G. Klingelhofer, C. Schroder, P.A. De Souza, D. W. Ming, Ralf Gellert, J. Zipfel, J. Brückner, J.F. Bell, Kenneth E. Herkenhoff, P. R. Christensen, S. Ruff, D. Blaney, S. Gorevan, N.A. Cabrol, L. Crumpler, J. Grant, L. Soderblom
Mars exploration rover geologic traverse by the spirit rover in the plains of Gusev crater, Mars
The Spirit rover completed a 2.5 km traverse across gently sloping plains on the floor of Gusev crater from its location on the outer rim of Bonneville crater to the lower slopes of the Columbia Hills, Mars. Using the Athena suite of instruments in a transect approach, a systematic series of overlapping panoramic mosaics, remote sensing observations, surface analyses, and trenching operations docu
Authors
L.S. Crumpler, S. W. Squyres, R. E. Arvidson, J.F. Bell, D. Blaney, N.A. Cabrol, P. R. Christensen, D.J. DesMarais, J.D. Farmer, R. Fergason, M.P. Golombek, F.D. Grant, J. A. Grant, R. Greeley, B. Hahn, Kenneth E. Herkenhoff, J.A. Hurowitz, A.T. Knudson, G. A. Landis, R. Li, J. Maki, H.Y. McSween, D. W. Ming, J.E. Moersch, M.C. Payne, J.W. Rice, L. Richter, S. W. Ruff, M. Sims, S.D. Thompson, N. Tosca, A. Wang, P. Whelley, S.P. Wright, M.B. Wyatt
Provenance and diagenesis of the evaporite-bearing Burns formation, Meridiani Planum, Mars
Impure reworked evaporitic sandstones, preserved on Meridiani Planum, Mars, are mixtures of roughly equal amounts of altered siliciclastic debris, of basaltic provenance (40 ± 10% by mass), and chemical constituents, dominated by evaporitic minerals (jarosite, Mg-, Ca-sulfates ± chlorides ± Fe-, Na-sulfates), hematite and possibly secondary silica (60 ± 10%). These chemical constituents and their
Authors
S. M. McLennan, J.F. Bell, W. M. Calvin, P. R. Christensen, B. C. Clark, P.A. de Souza, J. Farmer, W. H. Farrand, D.A. Fike, Ralf Gellert, A. Ghosh, T.D. Glotch, J.P. Grotzinger, B. Hahn, Kenneth E. Herkenhoff, J.A. Hurowitz, J. R. Johnson, S.S. Johnson, B. Jolliff, G. Klingelhofer, A.H. Knoll, Z. Learner, M. C. Malin, H.Y. McSween, J. Pocock, S. W. Ruff, Laurence A. Soderblom, S. W. Squyres, N.J. Tosca, W.A. Watters, M.B. Wyatt, A. Yen
Evidence from Opportunity’s Microscopic Imager for water on Meridiani Planum
The Microscopic Imager on the Opportunity rover analyzed textures of soils and rocks at Meridiani Planum at a scale of 31 micrometers per pixel. The uppermost millimeter of some soils is weakly cemented, whereas other soils show little evidence of cohesion. Rock outcrops are laminated on a millimeter scale; image mosaics of cross-stratification suggest that some sediments were deposited by flowing
Authors
Kenneth E. Herkenhoff, S. W. Squyres, R. Arvidson, D.S. Bass, J. F. III Bell, P. Bertelsen, B. L. Ehlmann, W. Farrand, Lisa R. Gaddis, R. Greeley, J. Grotzinger, A. G. Hayes, S.F. Hviid, J. R. Johnson, B. Jolliff, K.M. Kinch, A. H. Knoll, M.B. Madsen, J.N. Maki, S. M. McLennan, H.Y. McSween, D. W. Ming, J. W. Rice, L. Richter, M. Sims, P. H. Smith, Laurence A. Soderblom, Nicole Spanovich, R. Sullivan, S. Thompson, T. Wdowiak, C. Weitz, P. Whelley
Textures of the soils and rocks at Gusev Crater from Spirit’s Microscopic Imager
The Microscopic Imager on the Spirit rover analyzed the textures of the soil and rocks at Gusev crater on Mars at a resolution of 100 micrometers. Weakly bound agglomerates of dust are present in the soil near the Columbia Memorial Station. Some of the brushed or abraded rock surfaces show igneous textures and evidence for alteration rinds, coatings, and veins consistent with secondary mineralizat
Authors
Kenneth E. Herkenhoff, S. W. Squyres, R. Arvidson, D.S. Bass, J. F. III Bell, P. Bertelsen, N.A. Cabrol, Lisa R. Gaddis, A. G. Hayes, S.F. Hviid, J. R. Johnson, K.M. Kinch, M.B. Madsen, J.N. Maki, S. M. McLennan, H.Y. McSween, J. W. Rice, M. Sims, P. H. Smith, Laurence A. Soderblom, Nicole Spanovich, R. Sullivan, A. Wang
Magnetic properties experiments on the Mars Exploration Rover Spirit at Gusev Crater
The magnetic properties experiments are designed to help identify the magnetic minerals in the dust and rocks on Mars—and to determine whether liquid water was involved in the formation and alteration of these magnetic minerals. Almost all of the dust particles suspended in the martian atmosphere must contain ferrimagnetic minerals (such as maghemite or magnetite) in an amount of ∼2% by weight. Th
Authors
P. Bertelsen, W. Goetz, M.B. Madsen, K.M. Kinch, S.F. Hviid, J. M. Knudsen, H.P. Gunnlaugsson, J. Merrison, P. Nørnberg, S. W. Squyres, J. F. III Bell, Kenneth E. Herkenhoff, S. Gorevan, A. S. Yen, T. Myrick, G. Klingelhoefer, R. Rieder, R. Gellert