NASA's Mini Satellites Were Inspired by This Iconic '90s Toy

EVE and WALL-E, we hear you.

EVE and WALL-E finally made it off the screen, into real life, and straight to space. In this life, they’re high achievers.

Only eight minutes after the emotional success of InSight’s landing on the Martian surface, the Mars Cube One (MarCO) mission gave NASA scientists another reason to celebrate: NASA’s twin mini-satellites named EVE and WALL-E relayed data from InSight back to Earth at an unprecedented speed, eliminating hours of anxious toe-tapping by engineers at NASA’s Jet Propulsion Laboratory in California.

marCO diagram
MarCO will point their UHF antennas toward InSight as it descends to touch Martian soil with high gain X antennas pointed toward Earth to transmit data.

EVE and WALL-E, aka MarCO-A and MarCO-B, launched with the InSight back in May and trailed the lander to its final destination, observing its landing from above before sending signals home, 54.6 million kilometers away.

Of the 878 CubeSats launched as of October 28, 2018, MarCO CubeSats are the first to travel beyond Low-Earth Orbit (LEO), crowning them the farthest-traveled CubeSats by default.

marcos first photo moon earth
The first image captured by one of NASA's Mars Cube One (MarCO) CubeSats. 

For a class of spacecraft first mocked for its size, these tiny CubeSats have made huge leaps. Professors Jordi Puig-Suari of California Polytechnic State University and Bob Twiggs of Stanford University dreamt up CubeSats in 1998 as a teaching tool to give students hands-on experience while circumventing the prohibitive cost of space missions.

Inspired by Beanie Babies???

Twiggs was first inspired by a small plastic casing used to store Beanie Babies and wondered how he could launch one, reported Spaceflight Now in 2014. Since the first launch in 2003, the 10 x 10 x 11-centimeter mini-satellites have adopted missions from environmental monitoring to analyzing bacteria trapped in water ice.

In addition to tagging along behind InSight, WALL-E and EVE have more achievements to flex, as the pair were the first CubeSats to execute trajectory correction maneuvers with their experimental propulsion systems, which use R236FA gas, commonly found in fire extinguishers.

“[CubeSats will] never replace the more capable spacecraft NASA is best known for developing,” JPL Program Manager John Baker said on Tuesday. “But they’re low-cost ride-alongs that can allow us to explore in new ways.”

Where Are MarCO CubeSats Jetting to Next?

NASA only needed one CubeSat to complete the mission but sent a backup just in case. Despite sending both CubeSats for the same job, the satellites haven’t behaved the same.

“WALL-E has been a little bit trickier to control, and his cold-gas system has been a little less predictable, whereas EVE has been very straight-shot and very well-behaved,” Baker told Space.com. Seems like NASA chose the perfect names.

marcos in space
These interplanetary hitchhikers primarily ran on battery power while transmitting to Earth, as the orientation of the antennas weren't optimal for the solar arrays.

Now that the MarCO CubeSats completed their main mission, flying by Mars just 2,500 miles (4,000 kilometers) from the surface, NASA engineers are letting the pair wander, continuing their orbit around the sun. MarCO’s team isn’t sure how long EVE and WALL-E will continue their joyride, since no CubeSats have ventured this far before. But the little satellites may still have some work to do.

“Once they pass Mars, we’ll do some tracking to figure out where they ended up,” Baker said. “Then, we’ll see if there’s any option for what they could do in the future in terms of a convenient asteroid they could fly by or something like that.”

The MarCO CubeSats may also soon have interplanetary siblings. JPL’s INSPIRE project looks to one day send CubeSats to the harsh radiation of deep space, with an ambitious laundry list of asteroids, comets, Venus, Phobos, or Europa.

Media via NASA/JPL-Caltech (1, 2, 3, 4)