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The radar observations carried out on fourteen dates from May 2001 to July 2001 were designed to measure the surface properties of candidate landing sites for the Mars Exploration Rovers.
Chemical analysis of lunar surface at Surveyor 7 Tycho landing site
Alpha radioactivity of lunar surface at Surveyor 5, 6, and 7 landing sites
Determining LEM landing site inertial coordinates by CSM landmark sightings
A summary of the scientific rationale for each Apollo landing site listed by the Group for Lunar Exploration Planning on February 7, 1970 is presented. These sites include the Fra Mauro Formation, Littrow, Censorinus, Davy crater chain, Marius Hills, Descartes, Tycho, Copernicus central peaks, and Hadley-Apennines. In addition, a summary of the scientific rationale for Flamsteed P, the Apollo 13 backup site, and Hyginus is presented.
This abstract reports on preliminary evaluation of engineering constraints on potential landing sites for the Mars Sample Return missions.
Ejecta deposit modeling suggests that the megaregolith at the Apollo 16 landing site is dominated by Imbrium and Serenitatis ejecta, and Nectaris ejecta are a minor componen Additional information is contained in the original extended abstract.t.
About half of the rocks at the Mars Pathfinder Ares Vallis landing site appear to be ventifacts, rocks abraded by windborne particles.
Remote sensing data at scales of kilometers and an Earth analog were used to accurately predict the characteristics of the Mars Pathfinder landing site at a scale of meters. The surface surrounding the Mars Pathfinder lander in Ares Vallis appears consistent with orbital interpretations that it would be a rocky plain composed of materials deposited by catastrophic floods.
The traverse of the Mars Exploration Rover Opportunity across its Meridiani Planum landing site has shown that wind has affected regolith by creating drifts, dunes, and ubiquitous ripples, by sorting grains during aeolian transport, by forming bright wind streaks downwind from craters seen from orbit, and by eroding rock with abrading, wind-blown material. Pre-landing orbiter observations showed bright and dark streaks tapering away from craters on the Meridiani plains. Further analysis of orbiter images shows that major dust storms can cause bright streak orientations in the area to alternate between NW and SE, implying bright wind streak materials encountered by Opportunity are transient, potentially mobilized deposits. Opportunity performed the first in situ investigation of a martian wind streak, focusing on a bright patch of material just outside the rim of Eagle crater. Data from Pancam, the Miniature Thermal Emission Spectrometer (Mini-TES), the Alpha-Particle X-Ray Spectrometer (APXS), and the Mossbauer spectrometer either are consistent with or permit an air fall dust interpretation. We conclude that air fall dust, deposited in the partial wind shadow of Eagle crater, is responsible for the bright streak seen from orbit, consistent with models involving patchy, discontinuous deposits of air fall dust distributed behind obstacles during periods of atmospheric thermal stability during major dust storms.
This paper will present results of terrestrial delay-Doppler radar observations of the landing sites, predictions for the surface properties that will be encountered, and, after successful landings, correlation between the predicted and observed surface properties. The in-situ observations made by both missions serve as ground truth for the validation of the high resolution radar mapping results.
Preliminary results of chemical analysis of moon at Surveyor 7 landing site
Landing site redesignation during phase 2 of lunar module powered descent using primary guidance
Effects of descent engine throttle logic and initial altitude errors on landing site visibility
Elemental analyses of fines in the Martian regolith at two widely separated landing sites, Chryse Planitia and Utopia Planitia, produced remarkably similar results. At both sites, the uppermost regolith contains abundant Si and Fe, with significant concentrations of Mg, Al, S, Ca, and Ti. The S concentration is one to two orders of magnitude higher, and K (less than 0.25% by weight) is at least 5 times lower than the average for earth's crust. The trace elements Sr, Y, and possibly Zr have been detected at concentrations near or below 100 parts per million. Pebble-sized fragments sampled at Chryse contain more S than the bulk fines and are thought to be pieces of a sulfate-cemented duricrust.
Color changes at the Viking landing sites over the past Mars year are examined. Both sites exhibited an increased red to blue ratio of the soil due to the accumulation of a thin layer of bright red dust from the two global dust storms. The generation of bright areas on Mars and the formation of dark areas by stripping of bright dust layers are explained by the lander observations before the dust storm activity which show isolated bright red drifts which may be regions where material deposited during previous storms was protected from wind erosion.
The regional geology of the two Vega landing sites, where geochemical measurements on the Venusian surface were made, was studied using Magellan Cl-MIDRP imagery and MIT-processed altimetry for the large region which we will call the Vega region (22.90 deg. N to 22.90 deg. S and 154.12 deg. W to 211.12 deg. E). The results of the analysis were compiled in the form of a synoptic geologic map of about 1:10 m scale.
The regional geology of the five Venera landing sites, where geochemical measurements and TV observations on the Venusian surface were made, was studied based on the photogeologic analysis of the Magellan C1-MIDRP imagery for the large area that we will call the Venera region (38 deg. N to 22.6 deg. S and 268 to 344 deg. E). The results of the analysis were compiled in the form of a synoptical geologic map at about 1:10 M scale. MIT-processed Magellan altimetry was also used for the analysis.