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Davies, M. E.

Publications and source records attributed to Davies, M. E..

At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Mercury's surface - Preliminary description and interpretation from Mariner 10 pictures

The surface morphology and optical properties of Mercury resemble those of the moon in remarkable detail and record a very similar sequence of events. Chemical and mineralogical similarity of the outer layers of Mercury and the moon is implied; Mercury is probably a differentiated planet with a large iron-rich core. Differentiation is inferred to have occurred very early. No evidence of atmospheric modification of landforms has been found. Large-scale scarps and ridges unlike lunar or Martian features may reflect a unique period of planetary compression near the end of heavy bombardment by small planetesimals.

Murray, B. C.↗
NASA NTRS1974

Mariner 10 pictures of Mercury - First results

Mercury has a heavily cratered surface containing basins up to at least 1300 kilometers diameter flooded with mare-like material. Many features are closely similar to those on the moon, but significant structural differences exist. Major chemical differentiation before termination of accretion is implied.

Murray, B. C.↗
NASA NTRS1974

Photogrammetric measurements of Olympus Mons on Mars

Mariner 9 took many pictures of the giant Olympus Mons during its year in orbit around Mars. Control points have been identified on the top of Olympus Mons, on the volcanic shield, and on the surrounding plains, and their locations have been measured on the television pictures. These measurements were used to compute the areographic coordinates and the planetary radii of the points. The radii at some of the points were derived from radar elevation measurements and from radio occultation measurements. The mountain rises about 21 km above its base.

Davies, M. E.↗
NASA NTRS1974

Television observations of Mercury by Mariner 10

The morphology and optical properties of the surface of Mercury resemble that of the moon in remarkable detail, recording a very similar sequence of events; chemical and mineralogical similarity of the outer layers is implied. Mercury is probably a differentiated planet with an iron-rich core. Differentiation is inferred to have occurred very early. No evidence of atmospheric modification of any landform is found. Large-scale scarps and ridges unlike lunar or Martian features may reflect a unique period of planetary compression near the end of heavy bombardment, perhaps related to contraction of the core.

Murray, B. C.↗
NASA NTRS1973

Television experiment

The fixed and variable Martian features investigated by the TV experiment on Mariner 9 are described. Articles are presented concerning the dust storm of October to November over the Southern Hemisphere; global surface geodesy and cartography; geology; and the satellite astronomy.

Briggs, G. A.↗
NASA NTRS1973

Martian surface coordinates

The resolution of the pictures from the Mariner 9 mission determines the distribution of the control points, as well as the gaps in the planet-wide control net. After discussing the photogrammetric equations and the computational method used to establish the planet-wide control net and the secondary net, the camera stations and the assumed physical properties of Mars are considered. Subsequent paragraphs contain a description of the control points, their measurements, and a discussion of how distortions are removed. Finally, results of the computations are given, with tables of coordinates for the control points.

Davies, M. E.↗
NASA NTRS1973

Mariner 9 aerographic coordinate system

Preliminary Mariner 9 map products were based on computed aerocentric coordinates at the point where the optic path intercepts a spherical reference figure for Mars. The intercept point on a reference ellipsoid would in general have slightly different values of radius, latitude, and longitude. For near-vertical viewing used for mapping, these differences are on the order of 0.1 in latitude and longitude, which is negligible compared to the uncertainties of the initial uncontrolled mosaics and maps.

Devaucouleurs, G.↗
NASA NTRS1973

Martian surface coordinates.

This paper presents methods and results for primary and secondary triangulation of the Martian surface. The primary network is based on multiphotograph stereophotogrammetry in which the pictures are rotated around fixed centers; these centers are provided as spacecraft stations from the tracking data. The computations use the latest Mars spin axis determined by Mariner 9 experiments and the new first meridian passing through a small crater, Airy-0, seen on Mariner 9 imagery. The secondary triangulation is performed in the map plane using rectified pictures as map fragments, assumed to be of correct shape. In this paper, 1205 primary positions are given.

Davies, M. E.↗
NASA NTRS1973

Mariner 9 areographic coordinate system.

The basic elements of the physical ephemeris of Mars are reexamined, and the new values adopted for the Mariner 9 mapping are specified, in particular, for the direction of the spin axis and the first meridian.

De Vaucouleurs, G.↗
NASA NTRS1973

Control point measurements on Mariner 9 pictures

Measurements are given of the control points on the Mariner 9 pictures which were used in the computation of the June 1973 control net of Mars. The method of making the measurements is discussed along with the picture coordinate system and the removal of distortions. Table are presented of the 9804 measurements of 1645 points on 660 pictures.

Davies, M. E.↗
NASA NTRS1973

Mariner 9 control net Mars, June 1973

The latitude and longitude are reported for 1645 primary points in the control net of Mars. The points were derived from Mariner 9 photographs as of June 1973. The new Mariner 9 aerographic coordinates system used in performing the computations is discussed.

Davies, M. E.↗
NASA NTRS1973

Martian surface coordinates

Methods and results are presented for primary and secondary triangulation of the Martian surface. The primary network is based on multiphotograph stereophotogrammetry in which the pictures are rotated around fixed centers; these centers are provided as spacecraft stations from the tracking data. The computations use the latest Mars spin axis determined by Mariner 9 experiments and the new first meridian passing through a small crater, Airy-O, seen on Mariner 9 imagery. The secondary triangulation is performed in the map plane using rectified pictures as map fragments, assumed to be of correct shape. Primary positions are given.

Davies, M. E.↗
NASA NTRS1972

Mariner 9 control net of Mars, August 1972

Results are presented for a planet-wide geodetic control net of Mars which is based on Mariner 9 pictures as of August 1972. Aerocentric and aerographic coordinate of 809 control points were computed from 407 television frames. Photogrammetric parameters and methodology used in the computations are discussed. The coordinates of the features are given and figures that show the locations of the control points on the surface of Mars are included.

Davies, M. E.↗
NASA NTRS1972

Coordinates of features on the Mariner 6 and 7 pictures of Mars.

A control net of Mars has been computed from measurements of 115 control points identified on the Mariner 6 and 7 pictures. Most of these points are located with respect to topographic features on the surface of Mars, and their areographic coordinates were computed by photogrammetric techniques. These pictures offered the first opportunity to establish a control net of Mars based on topographic detail.

Davies, M. E.↗
NASA NTRS1972

Grand Tour outer planet missions definition phase. Part 2: Minutes of meetings and official correspondence

A variety of imaging systems proposed for use aboard the Outer Planet Grand Tour Explorer are discussed and evaluated in terms of optimal resolution capability and efficient time utilization. It is pointed out that the planetary and satellite alignments at the time of encounter dictate a high degree of adaptability and versatility in order to provide sufficient image enhancement over earth-based techniques. Data compression methods are also evaluated according to the same criteria.

Belton, M. J. S.↗