NASA could change MRO orbit to support March 2020

WASHINGTON – NASA is considering changing the orbit of one of its oldest spacecraft to Mars, an initiative meant to support the Mars 2020 mission after landing but which could affect both its science and the support of other missions.

NASA launched the Mars Reconnaissance Orbiter (MRO) in 2005 with a suite of six scientific instruments, including a high-resolution camera. The spacecraft has increasingly been used as a communications relay, supporting spacecraft on the surface of Mars.

In 2018, concerned about the aging of the spacecraft components, NASA proposed a potential change in the spacecraft’s orbit. MRO is currently in a sun-synchronous orbit which passes above the surface by mid-afternoon. NASA has proposed moving the spacecraft into an orbit with a crossing time later in the day to reduce the length of time each orbit is in the shadow of the planet. This would reduce the workload of the spacecraft’s batteries and prolong their life.

At the time, NASA said it would postpone a decision until the InSight mission lands in November 2018 and March 2020 in February 2021. With Mars 2020 just weeks away from landing, this decision to change MRO’s orbit is about to expire.

“Our intention is to make a decision after the landing and the initial operations of Mars 2020,” Eric Ianson, director of the NASA Mars Exploration Program, said at a Jan. 27 meeting of the Mars Exploration Program. Analysis Group (MEPAG).

Although the orbit change is aimed at extending the life of MRO, some scientists on Mars fear it will disrupt science. The different orbit would make it more difficult to compare the new observations with the previous ones. It could also affect the MRO’s ability to provide support to other missions, such as the Curiosity rover.

“We want to make sure we fully understand the benefits of staying in the current orbit and adjusting the orbit,” Ianson said. “I think people theoretically have an idea about it, but I don’t think we’ve looked at it completely and had a really deep discussion about it.

Michael Meyer, senior scientist for the Mars Exploration Program, told the MEPAG meeting that a potential change in the spacecraft’s orbit could have “a few other complications,” such as support for both Curiosity and the European Space Agency’s ExoMars mission, now slated for launch in 2022 after missing its mid-2020 launch window.

“We’re going to see it again” after the Mars 2020 landing, he said, “and do what the real trades are, and make a decision on the best thing to do for the global science of Mars.”

The communications infrastructure on Mars is a growing concern for scientists and mission planners. NASA relied on orbiters launched primarily for scientific missions to act as relays, including MRO as well as Mars Odyssey, launched in 2001, and MAVEN, launched in 2013.

Little progress has been made on proposals in recent years for new orbiter missions devoted to communications or communications as one of their primary roles. The most recent concept, presented at meetings in late 2020, called for a network of three satellites with inter-satellite links to provide continuous high-bandwidth communications for spacecraft both on the surface and in orbit. These spacecraft could be developed as part of a kind of business partnership.

This concept is most closely related to Mars Ice Mapper, a still-in-development mission that will pilot a radar mapping payload to search for ice deposits below the surface to support future robotic or human missions. According to NASA officials, this communications network would increase the amount of data the mission could return by a factor of 100.

Mars Ice Mapper and the proposed communications network will not launch until later in the decade, if approved. Ianson said a decision on changing MRO’s orbit to support March 2020 will be made “in the coming months.”