80°W 79°W 78°W 77°W 76°W 75°W

80°W

79°W

78°W

77°W 76°W 75°W

–7°

–6°

–5°

–4°

–3°

–7°

–6°

–5°

–4°

–3°

MC–17

MC–2

MC–3

MC–4

MC–8 MC–9 MC–10 MC–11

MC–1

MC–16 MC–18 MC–19

MC–24

MC–25

MC–26

MC–30

120°

120° 60°

60°

30°

65°

180° 135° 90° 45° 0°

–30°

–65°

30°

65°

–30°

–65°

280°E

–2.5°

281°E 282°E 283°E 284°E 285°E

280°E

281°E

282°E

283°E 284°E 285°E

–7.5°

–7°

–6°

–5°

–4°

–3°

–2.5°

–7.5°

–7°

–6°

–5°

–4°

–3°

0

3000

2000

–1000

–2000

1000

–2000

4000

3000

0

0

3000

2000

3000

4000

2000

0

1000

4000

0

1000

–1000

Ceti

Mensa

Candor Labes

CANDOR 

CHASMA

Tithoniae

Catenae

Perrotin

Tithoniae Fos sae

IUS CHASMA

Ius Labes

0

NOTES ON BASE

This map, compiled photogrammetrically from Viking Orbiter stereo image pairs, 

is part of a series of topographic maps of areas of special scientific interest on 

Mars.

ADOPTED FIGURE

The figure of Mars used for the computation of the map projection is an oblate 

spheroid (flattening of 1/176.875) with an equatorial radius of 3396.0 km and a 

polar radius of 3376.8 km (Kirk and others, 2000). The datum (the 0-km contour 

line) for elevations is defined as the equipotential surface (gravitational plus rotational) whose average value at the equator is equal to the mean radius as determined by Mars Orbiter Laser Altimeter (MOLA; Smith and others, 2001).

PROJECTION

The projection is part of a Mars Transverse Mercator (MTM) system with 20° wide 

zones. For the area covered by this map sheet the central meridian is at 290° E. (70° 

W.). The scale factor at the central meridian of the zone containing this quadrangle 

is 0.9960 relative to a nominal scale of 1:500,000.

COORDINATE SYSTEM

Longitude increases to the east and latitude is planetocentric as allowed by 

IAU/IAG standards (Seidelmann and others, 2002) and in accordance with current 

NASA and USGS standards (Duxbury and others, 2002). A secondary grid (printed 

in red) has been added to the map as a reference to the west longitude/planetographic latitude system that is also allowed by IAU/IAG standards (Seidelmann and 

others, 2002) and has been used for previous Mars maps.

CONTROL

Horizontal and vertical control was established using the Mosaicked Digital Image 

Model 2.0 (MDIM 2.0; Kirk and others, 2000) and MOLA data. A portion of 

MDIM 2.0 covering the mapping area was extracted in simple cylindrical projection. This MDIM image was georeferenced to the MOLA data with an affine transformation. The MDIM image and georeferencing information were imported into a 

digital photogrammetric workstation (Miller and Walker, 1993) and used as an 

orthophoto to provide horizontal control to stereopairs of Viking imagery. The horizontal information was used to extract vertical control from the MOLA data. Note 

that the distribution of Viking Orbiter images suitable for mapping at a scale of 

1:500,000 is uneven. Areas mapped in this series are chosen, often in blocks of two 

or more adjacent quadrangles, based on scientific interest as well as on the availability of suitable data for accurate mapping.

CONTOURS

Contours were derived from a digital terrain model (DTM) compiled on a digital 

photogrammetric workstation using Viking Orbiter stereo image pairs with orientation parameters derived from an analytic aerotriangulation. Contours were drawn 

automatically using a commercial geographic information system (GIS) software 

package (Environmental Systems Research Institute, 1994). For the stereomodels, 

the local expected vertical precision, based on image resolutions, parallax-to-height 

ratio (that is, convergence angle), and a matching accuracy of 0.2 pixel ranges from 

47 m to 199 m, with a mean of 87 m. Elevation (in meters) is given with respect to 

the adopted Mars topographic datum (see "Adopted Figure" section). A comparison 

of the DTM values at the MOLA point locations shows that the DTM is on average 

6 meters lower than the MOLA points (n=237,864; μ=-6 m; σ=213 m). Contour 

lines were generated automatically using GIS software and were not edited. 

Because the contour lines were not edited, small closed contour lines, contour lines 

that intersect, and contour lines that do not match features are present. The post 

spacing for the DTM is 600 m; features that are less than 600 m in size will not be 

resolved and features that are smaller than 1800 m in size may only have four elevation measurements associated with them. This lack of elevation measurements 

may result in contour lines that do not adequately represent some features. The purpose of this mapping project is to produce the digital orthophoto and DTM. This 

map provides a graphical representation of the digital products that are available.

IMAGE BASE

The image base for this map employs Viking Orbiter images from orbits 682, 608, 

912, and 334. An orthophotomosaic was created on the digital photogrammetric 

workstation using the DTM compiled from stereo models. Integrated Software for 

Imagers and Spectrometers (ISIS; Torson and Becker, 1997) provided the software 

to project the orthophotomosaic into the Transverse Mercator Projection.

NOMENCLATURE

Names on this sheet are approved by the International Astronomical Union (IAU). 

For a complete list of IAU approved names, see the Gazeteer of Planetary Nomenclature at http://planetarynames.wr.usgs.gov.

MTM 500k –05/282E OMKT: Abbreviation for Mars Transverse Mercator; 

1:500,000 series; center of sheet latitude 5° S., longitude 282.5° E. in 

planetocentric coordinate system (this corresponds to –05/077; latitude 5° 

S., longitude 77.5° W. in planetographic coordinate system); orthophotomosaic (OM) with color-coded (K) topographic contours and nomenclature (T) [Greeley and Batson, 1990]

REFERENCES

Duxbury, T.C., Kirk, R.L., Archinal, B.A., and Neumann, G.A., 2002, Mars Geodesy/Cartography Working Group Recommendations on Mars Cartographic 

Constants and Coordinate Systems, in Joint International Symposium on Geospatial Theory, Processing and Applications, Ottawa, Canada, 2002, Commission IV, Working Group 9—Extraterrestrial Mapping, Proceedings: Ottawa, 

Canada, International Society for Photogrammetry and Remote Sensing 

[http://www.isprs.org/commission4/proceedings/ paper.html].

Environmental Systems Research Institute, 1994, Arc commands: Redlands Calif., 

Environmental Systems Research Institute, Inc.

Greeley, Ronald, and Batson, R.M., 1990, Planetary mapping: New York, Cambridge University Press, p. 261–276.

Kirk, R.L., Lee, E.M., Sucharski, R.M., Richie, J., Grecu, A., and Castro, S.K., 

2000, MDIM 2.0: A revised global digital image mosaic of Mars in Lunar and 

Planetary Science XXXI:Houston, Lunar and Planetary Institute , abstract 

2011 [CD–ROM].

Miller, S.B., and Walker, A.S., 1993, Further developments of Leica Digital Photogrammetric Systems by Helava, ACSM/ASPRS Annual Convention and 

Exposition, Technical Papers, v. 3, p. 256–263.

Seidelmann, P.K. (chair), Abalakin, V.K., Bursa, M., Davies, M.E., De Bergh, C., 

Lieske, J.H., Oberst, J., Simon, J.L., Standish, E.M., Stooke, P., and Thomas, 

P.C., 2002, Report of the IAU/IAG Working Group on Cartographic Coordinates and Rotational Elements of the Planets and Satellites: 2000: Celestial 

Mechanics and Dynamical Astronomy, v. 82, p. 83–110.

Smith, D.E., Zuber, M.T., Frey, H.V., Garvin, J.B., Head, J.W., Muhleman, D.O., 

Pettengill, G.H., Phillips, R.J., Solomon, S.C., Zwally, H.J., Banerdt, W.B., 

Duxbury, T.C., Golombek, M.P., Lemoine, F.G., Neumann, G.A., Rowlands, 

D.D., Aharonson, O., Ford, P.G., Ivanov, A.B., McGovern, P.J., Abshire, J.B., 

Afzal, R.S., and Sun, X., 2001, Mars Orbiter Laser Altimeter (MOLA)–Experiment summary after the first year of global mapping of Mars: 

Journal of Geophysical Research, v. 106, p. 23,689–23,722.

Torson, J.M., and K.J., Becker, 1997, ISIS—A software architecture for processing 

planetary images (abs.), in Lunar and Planetary Science Conference XXVIII: 

Houston, Lunar and Planetary Institute, p. 1443.

NORTH

SOUTH

WEST

EAST

U.S. DEPARTMENT OF THE INTERIOR

U.S. GEOLOGICAL SURVEY

GEOLOGIC INVESTIGATIONS SERIES I–2805

Version 1.0

Prepared for the

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION

Prepared on behalf of the Planetary Geology and Geophysics Program, Solar System Exploration Division, Office of Space Science, 

National Aeronautics and Space Administration.

Manuscript approved for publication August 14, 2003

SCALE 1:502 000 (1 mm = 502 m) AT 290° E. (70° W.) LONGITUDE

TRANSVERSE MERCATOR PROJECTION

10 20 30 40 60 80 90 70 100 

KILOMETERS

CONTOUR INTERVAL 250 METERS

Planetocentric latitude and east longitude coordinate system shown in black.

Planetographic latitude and west longitude coordinate system shown in red.

10 50

QUADRANGLE LOCATION

Photomosaic showing location of map area. An outline of 

1:5,000,000-scale quadrangles is provided for reference.

6558

682608

4112

6663

6358

915917

4113

5866

648334

701586

6559

6365

5250

5000

4750 

4500 

4250 

4000 

3750 

3500 

3250 

3000 

2750 

2500 

2250 

2000 

1750 

1500 

1250 

1000 

750

500 

250 

0 

–250 

–500 

–750 

–1000 

–1250 

–1500 

–1750 

–2000 

–2250 

–2500 

–2750 

–3000 

–3250 

–3500 

–3750 

–4000 

–4250 

–4500 

–4750 

–5000 

–5250

Contour Guide, in meters

The following is a list of image pairs used to produce the topographic information 

for this map. Numbers below correspond to the numbers on the diagram above.

 ID IMAGE PAIR ID IMAGE PAIR ID IMAGE PAIR

915917 915A10–917A09 065A19–058A73 6358 063A44–058A73

 915A08–917A07 6559 065A22–059A25 063A43–058A77

701586 701A38–586A08 6365 063A47–065A27 063A43–058A75

682608 682A30–608A72 063A47–065A26 063A42–058A75

 682A29–608A72 063A46–065A26 063A42–058A73

648334 648A10–334A44 063A46–065A24 063A41–058A77

6663 066A20–063A45 063A45–065A27 063A41–058A75

 066A18–063A45 063A45–065A26 063A40–058A76

 066A18–063A43 063A45–065A25 5866 058A77–066A17

 066A16–063A43 063A45–065A23 058A77–066A15

 066A15–063A43 063A44–065A23 4112 041A30–012A13

6558 065A21–058A75 063A44–065A22 4113 041A20–013A13

 065A21–058A73 063A44–065A21

MTM –05/282E QUADRANGLE VIKING STEREOMODEL COVERAGE

Topographic Map of the West Candor Chasma Region of Mars

MTM 500k –05/282E OMKT

By

U.S. Geological Survey

2004

Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Dimensional calibration may vary between electronic plotters and between X and Y 

directions on the same plotter, and paper may change size due to atmospheric conditions; therefore, scale and proportions may not be true on plots of this map.

Digital files available on World Wide Web at http://pubs.usgs.gov/imap/i2805