The Mars Reconnaissance Orbiter (MRO) has sent back some incredible images and data from the Red Planet of the years, and it just hit an important milestone. It has now made 50,000 orbits of Mars since it arrived more than 11 years ago. Lockheed Martin really built this spacecraft to last.
MRO was launched in 2005 on an Atlas V rocket, and reached Mars in 2006. After aerobraking and tweaking its orbit, it settled in for a long mission. NASA couldn’t have known just how long, though; MRO has exceeded all expectations. We knew little about the surface topography of Mars before MRO, and now we know almost everything. Really — that’s not an exaggeration.
The Mars Reconnaissance Orbiter is equipped with several instruments that, combined, have allowed to to survey Mars to an incredible degree. Most of the high-resolution images NASA releases from MRO (like the one below) were taken with the HiRISE camera. It’s essentially a reflecting telescope with a camera attached. It has a resolution of 1 foot (0.3 meters) per pixel. That’s even better than the images you can look up on Google Maps right now. HiRISE is used for detailed examination of notable features on Mars.
Gullies and Bedrock in Nirgal Vallis, imaged by HiRISE
The Context Camera (CTX) is the real workhorse of this spacecraft. It has a lower resolution than HiRISE at just 20 feet (6 meters) per pixel. However, it can operate essentially nonstop. Using CTX, NASA has managed to map 99.1% of the Martian surface. It’s taken more than 90,000 images, each one about 18.6 miles (30 kilometers) across. Getting to almost total coverage with CTX is tricky because of weather, coordination with other instruments, data link conditions, and more. In order to get everything, NASA has ended up with a lot of redundancy. About 60% of Mars has been imaged by CTX more than once. This helps NASA track changes in the surface and verify landing zones for future missions. In fact, MRO recently helped find the landing location for NASA’s upcoming InSight lander.
There are many more orbits ahead of MRO. MRO Project Manager Dan Johnston says the spacecraft is “healthy and remains fully functional.” NASA executed an orbital adjustment shortly before the orbiter hit the 50,000 mark to ensure it’s overhead to receive radio transmissions from the InSight lander when it reaches Mars on November 26, 2018. It’s also using the HiRISE camera to get better photos of the InSight landing zone.