Publications
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The final Galileo SSI observations of Io: Orbits G28-I33 The final Galileo SSI observations of Io: Orbits G28-I33
We present the observations of Io acquired by the Solid State Imaging (SSI) experiment during the Galileo Millennium Mission (GMM) and the strategy we used to plan the exploration of Io. Despite Galileo's tight restrictions on data volume and downlink capability and several spacecraft and camera anomalies due to the intense radiation close to Jupiter, there were many successful SSI...
Authors
Elizabeth P. Turtle, Laszlo P. Keszthelyi, Alfred S. McEwen, Jani Radebaugh, Moses P. Milazzo, Damon P. Simonelli, Paul E. Geissler, David A. Williams, Jason Perry, Windy L. Jaeger, Kenneth P. Klaasen, H. Herbert Breneman, Tilmann Denk, Cynthia B. Phillips
Morphometric properties of Martian volcanoes Morphometric properties of Martian volcanoes
Mars Orbiter Laser Altimeter (MOLA) data have been used to construct Digital Elevation Models (DEM) of the Martian volcanoes in order to determine height, flank slope, caldera depth, and volumes. Summit elevations range from 21.1 km to −0.5 km, and relief varies from 1.0 km to almost 22 km. Average flank slopes are in the range of
Authors
J. B. Plescia
Reconciling different observations of the CO2 ice mass loading of the Martian north polar cap Reconciling different observations of the CO2 ice mass loading of the Martian north polar cap
The GRS measurements of the peak mass loading of the north polar CO2 ice cap on Mars are about 60% lower than those calculated from MGS TES radiation data and those inferred from the MOLA cap thicknesses. However, the GRS data provide the most accurate measurement of the mass loading. We show that the TES and MOLA data can be reconciled with the GRS data if (1) subsurface heat conduction...
Authors
Robert M. Haberle, Bridget Mattingly, Timothy N. Titus
The Spirit Rover's Athena science investigation at Gusev crater, Mars The Spirit Rover's Athena science investigation at Gusev crater, Mars
The Mars Exploration Rover Spirit and its Athena science payload have been used to investigate a landing site in Gusev crater. Gusev is hypothesized to be the site of a former take, but no clear evidence for lacustrine sedimentation has been found to date. Instead, the dominant lithology is basalt, and the dominant geologic processes are impact events and eolian transport. Many rocks...
Authors
S. W. Squyres, R. E. Arvidson, J.F. Bell, J. Bruckner, N.A. Cabrol, W. Calvin, M. H. Carr, P. R. Christensen, B. C. Clark, L. Crumpler, D.J. Des Marais, C. D'Uston, T. Economou, J. Farmer, W. Farrand, W. Folkner, M. Golombek, S. Gorevan, J. A. Grant, R. Greeley, J. Grotzinger, L. Haskin, Kenneth E. Herkenhoff, S. Hviid, J. Johnson, G. Klingelhofer, A. Knoll, G. Landis, M. Lemmon, R. Li, M.B. Madsen, M. C. Malin, S. M. McLennan, H.Y. McSween, D. W. Ming, J. Moersch, R.V. Morris, T. Parker, J. W. Rice, L. Richter, R. Rieder, M. Sims, M. Smith, P. Smith, Laurence A. Soderblom, R. Sullivan, H. Wanke, T. Wdowiak, M. Wolff, A. Yen
Basaltic rocks analyzed by the Spirit rover in Gusev crater Basaltic rocks analyzed by the Spirit rover in Gusev crater
The Spirit landing site in Gusev Crater on Mars contains dark, fine-grained, vesicular rocks interpreted as lavas. Pancam and Mini–Thermal Emission Spectrometer (Mini-TES) spectra suggest that all of these rocks are similar but have variable coatings and dust mantles. Magnified images of brushed and abraded rock surfaces show alteration rinds and veins. Rock interiors contain ≤25%...
Authors
H.Y. McSween, R. E. Arvidson, J.F. Bell, D. Blaney, N.A. Cabrol, P. R. Christensen, B. C. Clark, J.A. Crisp, L.S. Crumpler, D.J. Des Marias, J.D. Farmer, Ralf Gellert, A. Ghosh, S. Gorevan, T. Graff, J. Grant, L.A. Haskin, Kenneth E. Herkenhoff, J. R. Johnson, B.L. Jolliff, G. Klingelhoefer, A.T. Knudson, S. McLennan, K.A. Milam, J.E. Moersch, R.V. Morris, R. Rieder, S. W. Ruff, P.A. De Souza, S. W. Squyres, H. Wanke, A. Wang, M.B. Wyatt, A. Yen, J. Zipfel
In situ evidence for an ancient aqueous environment at Meridiani Planum, Mars In situ evidence for an ancient aqueous environment at Meridiani Planum, Mars
Sedimentary rocks at Eagle crater in Meridiani Planum are composed of fine-grained siliciclastic materials derived from weathering of basaltic rocks, sulfate minerals (including magnesium sulfate and jarosite) that constitute several tens of percent of the rock by weight, and hematite. Cross-stratification observed in rock outcrops indicates eolian and aqueous transport. Diagenetic...
Authors
S. W. Squyres, J.P. Grotzinger, R. E. Arvidson, J.F. Bell, W. Calvin, P. R. Christensen, B. C. Clark, J.A. Crisp, W. H. Farrand, Kenneth E. Herkenhoff, J. R. Johnson, G. Klingelhofer, A.H. Knoll, S. M. McLennan, H.Y. McSween, R.V. Morris, J. W. Rice, R. Rieder, Laurence A. Soderblom
Soils of eagle crater and Meridiani Planum at the opportunity Rover landing site Soils of eagle crater and Meridiani Planum at the opportunity Rover landing site
The soils at the Opportunity site are fine-grained basaltic sands mixed with dust and sulfate-rich outcrop debris. Hematite is concentrated in spherules eroded from the strata. Ongoing saltation exhumes the spherules and their fragments, concentrating them at the surface. Spherules emerge from soils coated, perhaps from subsurface cementation, by salts. Two types of vesicular clasts may...
Authors
Laurence A. Soderblom, R. C. Anderson, R. E. Arvidson, J.F. Bell, N.A. Cabrol, W. Calvin, P. R. Christensen, B. C. Clark, T. Economou, B.L. Ehlmann, W. H. Farrand, D. Fike, Ralf Gellert, T.D. Glotch, M.P. Golombek, R. Greeley, J.P. Grotzinger, Kenneth E. Herkenhoff, D.J. Jerolmack, J. R. Johnson, B. Jolliff, C. Klingelhofer, A.H. Knoll, Z.A. Learner, R. Li, M. C. Malin, S. M. McLennan, H.Y. McSween, D. W. Ming, R.V. Morris, J. W. Rice, L. Richter, R. Rieder, D. Rodionov, C. Schroder, F.P. Seelos, J.M. Soderblom, S. W. Squyres, R. Sullivan, W.A. Watters, C.M. Weitz, M.B. Wyatt, A. Yen, J. Zipfel
Imaging Borrelly Imaging Borrelly
The nucleus, coma, and dust jets of short-period Comet 19P/Borrelly were imaged from the Deep Space 1 spacecraft during its close flyby in September 2001. A prominent jet dominated the near-nucleus coma and emanated roughly normal to the long axis of nucleus from a broad central cavity. We show it to have remained fixed in position for more than 34 hr, much longer than the 26-hr rotation...
Authors
Laurence A. Soderblom, D. C. Boice, D.T. Britt, R. H. Brown, B. J. Buratti, Randolph L. Kirk, M. Lee, R.M. Nelson, J. Oberst, B.R. Sandel, S. A. Stern, N. Thomas, R.V. Yelle
Observations and temperatures of Io's Pele Patera from Cassini and Galileo spacecraft images Observations and temperatures of Io's Pele Patera from Cassini and Galileo spacecraft images
Pele has been the most intense high-temperature hotspot on Io to be continuously active during the Galileo monitoring from 1996–2001. A suite of characteristics suggests that Pele is an active lava lake inside a volcanic depression. In 2000–2001, Pele was observed by two spacecraft, Cassini and Galileo. The Cassini observations revealed that Pele is variable in activity over timescales...
Authors
Jani Radebaugh, Alfred S. McEwen, Moses P. Milazzo, Laszlo P. Keszthelyi, Ashley G. Davies, Elizabeth P. Turtle, Douglas D. Dawson
Surface changes on Io during the Galileo mission Surface changes on Io during the Galileo mission
A careful survey of Galileo SSI global monitoring images revealed more than 80 apparent surface changes that took place on Io during the 5 year period of observation, ranging from giant plume deposits to subtle changes in the color or albedo of Patera surfaces. Explosive volcanic activity was discovered at four previously unrecognized centers: an unnamed patera to the south of Karei that...
Authors
Paul E. Geissler, Alfred McEwen, Cynthia B. Phillips, Laszlo P. Keszthelyi, John Spencer
Mapping of the Culann-Tohil region of Io from Galileo imaging data Mapping of the Culann-Tohil region of Io from Galileo imaging data
We have used Galileo spacecraft data to produce a geomorphologic map of the Culann–Tohil region of Io's antijovian hemisphere. This region includes a newly discovered shield volcano, Tsũi Goab Tholus and a neighboring bright flow field, Tsũi Goab Fluctus, the active Culann Patera and the enigmatic Tohil Mons-Radegast Patera–Tohil Patera complex. Analysis of Voyager global color and...
Authors
D.A. Williams, Paul M. Schenk, Jeffrey M. Moore, Laszlo P. Keszthelyi, Elizabeth P. Turtle, Windy L. Jaeger, Jani Radebaugh, Moses P. Milazzo, Rosaly Lopes, Ronald Greeley
Short-wavelength infrared (1.3-2.6 μm) observations of the nucleus of Comet 19P/Borrelly Short-wavelength infrared (1.3-2.6 μm) observations of the nucleus of Comet 19P/Borrelly
During the last two minutes before closest approach of Deep Space 1 to Comet 19P/Borrelly, a long exposure was made with the short-wavelength infrared (SWIR) imaging spectrometer. The observation yielded 46 spectra covering 1.3–2.6 μm; the footprint of each spectrum was ∼160 m × width of the nucleus. Borrelly's highly variegated and extremely dark 8-km-long nucleus exhibits a strong red...
Authors
Laurence A. Soderblom, D.T. Britt, R. H. Brown, B. J. Buratti, Randolph L. Kirk, T.C. Owen, R.V. Yelle