A Meteor Smashed Into Mars in 2005, Making this Crater

NASA has repeatedly imaged the Martian surface, and sometimes a feature appears that wasn’t there in prior images. That’s what happened when a meteorite survived the plunge through Mars’ thin atmosphere sometime between February and July, 2005. It created this impact crater north of Valles Marineris.

This image is from the HiRISE (High Resolution Imaging Experiment) instrument on NASA’s Mars Reconnaissance Orbiter (MRO), and was taken when the spacecraft was 260.1 km (161.6 miles) above the surface. The blue color most likely represents basaltic rock, according to NASA, which is formed from rapidly-cooling lava. It’s spread over the surface in what’s called an ejecta blanket.

Another view of the crater that struck Mars sometime between February and July, 2005. Image Credit: NASA/JPL/UoArizona
Another view of the crater that struck Mars sometime between February and July, 2005. Image Credit: NASA/JPL/UoArizona

When a meteorite strikes the surface of a planet, it forms a crater and an ejecta blanket. The radial lines spreading out from the crater are called “rays”. The rays are the fine features of the impact, and over time they’re erased by erosion. A crater with rays is a young one.

Before and after images of the crater site. Image Credit: NASA/JPL/UofArizona
Before and after images of the crater site. Image Credit: NASA/JPL/UofArizona

These meteorite strikes also remove loose surface material and expose a deeper layer. This allows scientists to get a glimpse of the planet under the cover of its dust, and to study its subsurface.

In this image the crater is marked by a small white rectangle near the center of the image. Valles Mariners is to the south. Image Credit: NASA/MOLA/USGS
In this image the crater is marked by a small white rectangle near the center of the image. Valles Mariners is to the south. Image Credit: NASA/MOLA/USGS

The image of the 2005 crater is one of the HiRISE Pictures of the Day (POD). HiPOD often features craters, and the images are fascinating.

This impact crater is in Noachis Terra on Mars. Most craters have a plain bowl shape, but this one is being shaped by surface processes. This crater is 300 m (984 ft) in diameter. Image Credit: NASA/JPL/UofArizona
This impact crater is in Noachis Terra on Mars. Most craters have a plain bowl shape, but this one is being shaped by surface processes. This crater is 300 m (984 ft) in diameter. Image Credit: NASA/JPL/UofArizona
This crater has a tiny crater within it. The image is from between March 2017 and June 2019. Image Credit: NASA/JPL/UofArizona
This crater has a tiny crater within it. The image is from between March 2017 and June 2019. Image Credit: NASA/JPL/UofArizona
Over time, all craters erode away. This one is pretty old, and its rim has eroded away in several spots. Image Credit: NASA/JPL/UofArizona
Over time, all craters erode away. This one is pretty old, and its rim has eroded away in several spots. Image Credit: NASA/JPL/UofArizona

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