AVIATION WEEK AEROSPACE DAILY & DEFENSE REPORT Daily business intelligence for the global aerospace and defense industry
February 24, 2017
Vol. 259 Issue 37
NASA Anticipates 2021 Mars Traffic Jam
Mars could get pretty congested with spacecraft in early 2021 thanks to an emerging global lineup of missions eager to take advantage of a mid-2020 launch opportunity that leverages a favorable alignment between Earth and the Red Planet every 26 months.
Mars could have what one expert termed an "armada" of rovers, stationary landers and orbiters converging on the planet at much the same time.
Count NASA's Mars 2020 rover, the joint European/Russian ExoMars 2020 rover and lander; SpaceX's first Red Dragon lander; a Chinese rover and orbiter and the United Arab Emirates' first bid at Mars orbit insertion with its Hope spacecraft as those potentially converging on the Martian realm to create a February 2021 traffic jam.
NASA, the space agency best equipped to serve as "air traffic control" for the convergence, is already assessing what all the activity could mean for its already much-in-demand Deep Space Network (DSN)--a lineup of large dish antennas strategically placed in Spain, Australia and California--and a largely U.S. fleet of spacecraft already orbiting Mars. Together, they serve as Earth-based data collectors and Mars orbiting communications relays for U.S. and international partner spacecraft operating in the Martian realm. The NASA Jet Propulsion Laboratory-managed DSN, whose roots go back more than a half century, operates 24/7. DSN serves as the communications home base for 40 to 50 science missions at any one time operating between low Earth orbit and the edge of interstellar space.
"The Deep Space Network will be exceptionally challenged. There is no question about that," James Watzin, NASA's Mars Exploration Program director, told those gathered Feb. 22 in Monrovia, California, and by internet connection for the opening session of a two-day meeting of the Mars Exploration Program Analysis Group (Mepag). The group is a collection of experts chartered by NASA to assist the agency with planning the scientific exploration of the Red Planet.
Missions far from Mars may have to sacrifice contact time with Earth through the DSN to accommodate the planetary traffic jam.
"That is part of a study that we are doing right now to look at how we could manage that. Almost everybody that goes to Mars depends on the DSN for delta velocity and position tracking. Everyone will want to converge their solution to approach at the same point in time. So there will be an exceptionally high demand to provide that," Watzin predicts.
Now cold and desert-like, the Red Planet has become an increasingly compelling, if expensive, destination, because of growing evidence it once hosted a warmer, wetter environment perhaps favorable for microbial activity. Vestiges of past astrobiology might even currently thrive on Mars, some planetary scientists believe.
SpaceX, the Hawthorne, California-based commercial space company, and MarsOne, a Dutch nonprofit, have also stirred interest worldwide in establishing human colonies on Mars.
NASA's Mars 2020 rover, developed with technologies pioneered by the successful Mars Curiosity rover, is to lift off during the favorable July/August 2020 launch window when the Earth and Mars are aligned to reach the Red Planet in February 2021. During its primary mission, Mars 2020 will gather and cache small samples of soil and rock that can be returned to Earth at some point in the future for analysis by scientists in labs equipped with the latest technology. The Mars 2020 rover will also demonstrate a technology for extracting oxygen from the thin carbon dioxide Martian atmosphere. Oxygen could provide a life support and propellant resource for future human explorers.
The European Space Agency's EXOMars rover will search for signs of life as it rolls across the Martian terrain with a drill and other state-of-the-art instrumentation, including the Mars Organic Molecule Analyzer (MOMA). NASA is partnering with ESA in the MOMA development, an incentive for it to help direct traffic.
"We will probably need an extraordinarily large share of DSN support for those activities, and it will require several years of planning," Watzin told the Mepag gathering. "So we are preparing an efficient plan for handling it. That is what we are starting to build on right now. I think it's all doable, but it's certainly going to be very challenging."
Mars, with eight currently functioning international spacecraft either orbiting or roving its terrain, is already an air traffic control challenge, according to Fuk Li, director of JPL's Mars exploration directorate. Part of the challenge is sharing orbital space with one of the planet's two small moons, Phobos. "We are worried about our orbiters colliding with one another. We worry that some of them may collide with Phobos," explained Li, who said JPL has responded by serially modeling the orbital trajectories of the Mars orbiters. "If we get close together, or we project that they will get close together, we will alert all the missions and watch (the spacecraft) to see how they progress. Typically, we don't have to do anything over time. The concern resolves itself."
But just before the long U.S. President's Day weekend, the forecasting raised concerns over conjunctions between NASA's Maven and Mars Odyssey orbiters, and Maven and Phobos.
"We are watching them," Li said. "I believe that as time goes on, chances are they will get themselves resolved. If not, one of the missions, most likely Maven, will have to do some sort of orbit adjustment. So far, we have not had to do it. We are watching to make sure they don't get too close to one another."
ESA's Trace Gas Orbiter, which maneuvered into an initial orbit at Mars in October, is to tighten the circle with a period of aerobraking set to begin in mid-March. It will be monitored by JPL, Li said.
--Mark Carreau, firstname.lastname@example.org