The current, much narrower landing ellipse of Curiosity in the Gale Crater
Choosing the right landing site for a Mars mission is always a long process in which engineers and scientists need to find ‘common ground’. The list of 100 potential sites for the MSL mission had to be whittled down to one. And within that one landing site the team had to choose the best spot for the actual landing.
This spot needs to give speedy access to terrain that has the best potential for significant science findings.
While the rover is en route to Mars the team keeps whittling down the exact spot for touchdown of the rover within the chosen landings spot. Recently NASA has narrowed the target for Curiosity to 7 by 20 kilometers (approximately 4 miles wide and 12 miles long) instead of the 20 kilometers by 25 kilometers (12 miles wide and 16 miles long ), that had been NASA’s aim before Curiosity was launched on 26 November 2011.
This is a very purposeful action as by trimming the overall width and length of the landing site, the drive after landing to the central mountain in the crater has been cut by almost half.
That could get Curiosity to the mountain months earlier, than originally estimated. Geologists expect interesting scientific findings in the mountain rocks.