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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 Galileo Solid-S
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 M.C. Lopes, Ronald Greeley

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 observations du
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

The opportunity Rover's Athena science investigation at Meridiani Planum, Mars

The Mars Exploration Rover Opportunity has investigated the landing site in Eagle crater and the nearby plains within Meridiani Planum. The soils consist of fine-grained basaltic sand and a surface lag of hematite-rich spherules, spherule fragments, and other granules. Wind ripples are common. Underlying the thin soil layer, and exposed within small impact craters and troughs, are flat-lying sedim
Authors
S. W. Squyres, R. E. Arvidson, J.F. Bell, J. Brückner, 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.H. 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

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 features includ
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

Pancam multispectral imaging results from the opportunity Rover at Meridiani Planum

Panoramic Camera (Pancam) images from Meridiani Planum reveal a low-albedo, generally flat, and relatively rock-free surface. Within and around impact craters and fractures, laminated outcrop rocks with higher albedo are observed. Fine-grained materials include dark sand, bright ferric iron-rich dust, angular rock clasts, and millimeter-size spheroidal granules that are eroding out of the laminate
Authors
J.F. Bell, S. W. Squyres, R. E. Arvidson, H.M. Arneson, D. Bass, W. Calvin, W. H. Farrand, W. Goetz, M. Golombek, R. Greeley, J. Grotzinger, E. Guinness, A. G. Hayes, M.Y.H. Hubbard, Kenneth E. Herkenhoff, M. J. Johnson, J. R. Johnson, J. Joseph, K.M. Kinch, M.T. Lemmon, R. Li, M.B. Madsen, J.N. Maki, M. Malin, E. McCartney, S. McLennan, H.Y. McSween, D. W. Ming, R.V. Morris, E.Z. Noe Dobrea, T. J. Parker, J. Proton, J. W. Rice, F. Seelos, J.M. Soderblom, Laurence A. Soderblom, J. N. Sohl-Dickstein, R.J. Sullivan, C.M. Weitz, M.J. Wolff

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 represent
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

Localization and physical property experiments conducted by opportunity at Meridiani Planum

The location of the Opportunity landing site was determined to better than 10-m absolute accuracy from analyses of radio tracking data. We determined Rover locations during traverses with an error as small as several centimeters using engineering telemetry and overlapping images. Topographic profiles generated from rover data show that the plains are very smooth from meter- to centimeter-length sc
Authors
R. E. Arvidson, R. C. Anderson, P. Bartlett, J.F. Bell, P. R. Christensen, P. Chu, K. Davis, B.L. Ehlmann, M.P. Golombek, S. Gorevan, E.A. Guinness, A. F. C. Haldemann, Kenneth E. Herkenhoff, G. Landis, R. Li, R. Lindemann, D. W. Ming, T. Myrick, T. Parker, L. Richter, F.P. Seelos, Laurence A. Soderblom, S. W. Squyres, R.J. Sullivan, Jim Wilson

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% megacrysts. Chem
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

Comparison of USGS and DLR topographic models of Comet Borrelly and photometric applications

Stereo analysis of images obtained during the 2001 flyby of Comet Borrelly by NASA's Deep Space 1 (DS1) probe allows us to quantify the shape and photometric behavior of the nucleus. The shape is complex, with planar facets corresponding to the dark, mottled regions of the surface whereas the bright, smooth regions are convexly curved. The photometric as well as textural differences between these
Authors
Randolph L. Kirk, Elpitha Howington-Kraus, Laurence A. Soderblom, Bernd Giese, Jürgen Oberst

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 period. T
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

The nucleus of Comet Borrelly: A study of morphology and surface brightness

Stereo images obtained during the DS1 flyby were analyzed to derive a topographic model for the nucleus of Comet 19P/Borrelly for morphologic and photometric studies. The elongated nucleus has an overall concave shape, resembling a peanut, with the lower end tilted towards the camera. The bimodal character of surface-slopes and curvatures support the idea that the nucleus is a gravitational aggreg
Authors
J. Oberst, Elpitha Howington-Kraus, Randolph L. Kirk, Laurence A. Soderblom, B. Buratti, M. Hicks, R. Nelson, D. Britt

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 of minutes,
Authors
Jani Radebaugh, Alfred S. McEwen, Moses P. Milazzo, Laszlo P. Keszthelyi, Ashley G. Davies, Elizabeth P. Turtle, Douglas D. Dawson