Smaller And More Recent Features On Mars Can Now Be Dated

This image, from NASA's Mars Global Surveyor, shows a young lava flow (darker formation in lower middle part of picture) lying atop an older surface on Mars (lighter regions, upper right and lower left). The lava flow has visibly fewer impact craters than the background terrain, illustrating the general principle that crater numbers can reveal ages of surfaces. The 500-meter scale bar is approximately 500 yards long, or the length of 5 football fields. Image Credit: NASA, JPL and Malin Space Science Systems. by Staff Writers Tucson AZ (SPX) Oct 13, 2008 The crater-counting system that scientists have used since the 1970s to determine the age of large geologic features on Mars will also allow them to date small features, such as riverbeds and lava flows, according to William K. Hartmann, a senior scientist at the Tucson-based... [read full story]