|
 |
 advertisement
| |
|
|
|
|
|
Mars Orbiter Camera Reveals Rifts and Cracks in Martian Polar Terrain
posted: 10:18 am ET
16 November 1999
|
mars-polarice_991115Bright lines reminiscent of the cracked clay in a dry lake bed on Earth crisscross areas of Mars' polar regions, and may indicate the presence of water ice, some scientists believe. Pictures taken by the Mars Orbiter Camera aboard the Mars Global Surveyor spacecraft in October show a landscape that seems divided into polygonal puzzle pieces by the rift-like cracks. The area shown in these images lies deep in the planet's southern hemisphere -- a region now experiencing a gradual springtime warming. Until recently, the surface was covered by the icy white frost of winter. As the frost retreats, some is left behind in cracks. The brighter lines may be low-lying depressions where the more-reflective frost has not yet melted. Similar features are found on Earth in areas where a good deal of ice is frozen in the ground. The features seem to be produced by cycles of freezing and thawing over years, decades and centuries. 
This image, part of the Malea Planum flatlands near Mars' south pole, shows an area about three-quarters of a mile (1.25 kilometer) wide. It was taken by the Mars Global Surveyor's Mars Orbiter Camera in October, 1999. Photo courtesy NASA, JPL and Malin Space Science Systems.
|
|
|
|
|
