NASA’s InSight lander has touched down on Mars today (Nov. 26), where it will begin its mission to study “Marsquakes” (land shaking on Mars) and the Red Planet’s core.
Insight’s landing area is somewhere in a big oval, situated on the very flat, safe region Elysium Planitia. The flat part makes sense; there’s no sense dropping an $850 million piece of equipment somewhere rocky. But why the big oval shape?
Insight could land just about anywhere in an elliptical region about 81 miles (130 kilometers) by 17 miles (27 km) at its widest point, according to Jet Propulsion Laboratory scientist Matt Golombek — though the lander will most likely end up closer to the middle of that region.

source: livescience.com