The Small Satellites Paving The Way For Low-Cost Exploration Of Deep Space

NASA’s latest Mars mission is being accompanied by two small escorts that could transform the future of space exploration.
Fast Company, May 4, 2018

NASA’s next Mars mission, the InSight lander, is due to launch this Saturday, May 5, from Vandenberg Air Force base in California, the agency’s first interplanetary launch from the West Coast. In the works since 2010, the mission will shed new light on the interior of the red planet—and on the history of our own blue one—at a cost of more than $825 million. But it will also be accompanied by two small escorts that NASA hopes will one day allow us to explore deep space on the cheap.

The Atlas rocket that carries the spacecraft is due to launch at 4:05 a.m. PST. About 90 minutes later, once the upper stage leaves Earth’s atmosphere and orbit, the InSight lander itself will separate and will be on its way to Mars—a trip that will take about six months.

InSight will be followed closely by two small friends that will separate from the upper stage immediately after the lander: cubesats known as Mars Cube One, or MarCO, that measure no more than 36 cm (14 inches) on a side before their solar panels and antennas are deployed. While their job on the InSight mission will be to relay information about the lander as it descends to the planet’s surface, it is NASA’s hope that these two tiny spacecraft can demonstrate a new mode of interplanetary space exploration—one that costs considerably less than the full-scale missions that are the only thing that’s been possible until now.

Once InSight reaches Mars, “it goes through seven minutes of terror as it passes through the atmosphere and slows from interplanetary speeds to a soft landing,” says MarCO chief engineer Andy Klesh. “As InSight travels through the EDL [Entry, Descent, and Landing] process, we always like to receive real-time information—minus the light delay—so that if anything does go wrong, we can pass on the lessons toward missions in the future.”

That information would normally be relayed to Earth by NASA’s Odyssey spacecraft, which has been in orbit around Mars since 2001. But Odyssey will be in the wrong position to keep tabs on InSight, so NASA’s Jet Propulsion Laboratory needed another solution.

Enter MarCO. During EDL, InSight will transmit information to MarCO, and MarCO will boost and relay that signal to the 70-meter Deep Space Network antenna in Madrid. While it seems a relatively minor task for a mission that will span the vast distance between the Earth and Mars, it represents an important example of the utility of cubesats in deep space.

“The most important piece about MarCO as a tech demo is that it is a precursor to so many other missions and opportunities,” Klesh says. Among them is Exploration Mission 1, the first flight test of NASA’s planned platform for the human exploration of deep space. While EM-1 will send the Orion spacecraft into an orbit around the moon, it will also carry 13 cubesats that will do everything from searching for lunar ice to launching the solar system’s first space-weather station.

“The ability to launch small cubesats as secondary craft means we can reach many more opportunistic locations for science for proving out the technology for larger missions to come,” Klesh says. Among these, Klesh cites the fires of Io, Jupiter’s fifth moon, which is home to volcanoes that send plumes of sulfur as much as 300 kilometers (190 miles) above the surface. “Small spacecraft provide an ability to get out there with a focused science question before we send something much larger,” Klesh says.

MarCO will be the first cubesats to travel beyond low Earth orbit—well beyond. To make the 158 million-kilometer trip to Mars, the team has planned five “major trajectory correction maneuvers,” the exact parameters of which will need to be determined during flight. To accomplish this, JPL had to design a radio small enough to fit in the cubesat yet powerful enough to communicate with Earth.

“These really extreme volume constraints have forced us to really rethink and recreate everything,” says John Baker, who manages the small satellite programs at JPL. “The schedule and cost constraints also created a lot of innovation. We started off actually coming up with ideas that were not quite at the same performance level of big spacecraft. But we’ve very rapidly managed to create new instruments, and new sensors, and new technologies that actually exceed what some of our large spacecraft can do in performance, with some exceptions.”

Propulsion is a challenge, Baker notes: “Physics still dictates certain things.” To solve the challenge, the satellites’ propulsion system (provided by Vacco Industries) will use the same gas found in modern fire extinguishers—which is why the team at JPL calls the two cubesats Wall-E and Eva, after the Disney characters who propelled themselves through space in a similar manner.

Many other components of the cubesats will incorporate commercially available technologies, including an ultra-low-power microprocessor, the Texas Instruments MSP430, commonly found in toasters, showerheads, and razors, Klesh says, as well as solar panels from MMA Design, and an attitude control and position system from Blue Canyon Technologies. Using off-the-shelf technologies is part of what keeps the cost for the mission at a fraction of the total cost for InSight. (“Headquarters has put out a number of $18.5 million from initial conception through operations” for MarCO, Klesh says.)

The cubesats NASA is sending with InSight and EM-1 will help larger craft reach further into the solar system, according to Baker. And as cubesats and larger missions push deeper into space, NASA sees more private-sector companies getting involved. “Deep space spacecraft may look the same and sound the same, but underneath the aluminum is a very different spacecraft,” Baker says. “The environment is just so much more extreme in deep space. The radiation is worse, the thermal environment is worse, the distances are greater, the power is less.”

“Going forward, this will translate to allowing us to go places and do measurements that we haven’t been able to make before,” he says. “The further out you go, it gets harder and harder to send a big spacecraft.” In some cases, sending a smaller satellite first will help lower the risk for larger missions to follow.

“The major aspect to MarCO is that it is truly a technology demonstration and high-risk endeavor, very much in the spirit of NASA,” Klesh says. “We see MarCO as only the first in a long line of small satellite explorers looking at new worlds and new opportunities.”