Scientists working with the Mars Odyssey spacecraft say that it’s not uncommon for multiple pieces of a meteor to impact Mars close together at the same time. Here, a triple crater was formed simultaneously when three pieces of a meteor struck Mars’ surface together. When this happens, the craters that are formed overlap and the force of the impacts results in a linear wall separating the craters that form side-by-side. This image is part of a larger image swath taken by the THEMIS instrument (Thermal Emission Imaging System) on the Odyssey spacecraft. On another part of this larger image, there’s also a double crater.
This double crater appears to be different, however, from the triple crater in that the two craters were likely formed at different times. The smaller crater to the left appears older, since material from when the second, larger crater to the right was formed has been thrown into the crater on the left. The crater on the left appears more eroded and weathered, as well.
Here’s the entire image swath from Odyssey:
The Mars Odyssey spacecraft arrived at Mars on October 24, 2001, and has been mapping the surface of the Red Planet since February 2002.
Click here to see a map of Mars where these craters are located.
Original News Source: THEMIS/Mars Odyssey webpage