Paper-Thin Spacecraft Could Take Out the Trash in Space

An artist’s conception of Brane Craft about to capture a piece of space debris. (Graphic: Joseph Hidalgo)

NASA has awarded Aerospace a grant to investigate the possibility of developing an extremely thin spacecraft that would wrap around debris and remove it from Earth’s orbit.

The innovative concept, called Brane Craft, is a 1-meter square spacecraft that is less than half the thickness of a human hair, and therefore exceptionally light, maneuverable, and fuel efficient.

“The Brane Craft concept is based on the one-dimensional compression of a complete spacecraft and upper stage into an essentially two-dimensional object in order to maximize power-to-weight and aperture-to-weight ratios,” said Dr. Siegfried Janson, the lead investigator on this project.

If you have trouble wrapping your brane, er brain, around the concept, think of the spacecraft as a large piece of high-tech plastic wrap zipping through space and enveloping flying garbage.

The Brane Craft is one of 13 ideas that were picked for the NASA Innovative Advanced Concepts (NIAC) program, which, according to NASA, “nurtures visionary ideas that could transform future NASA missions with the creation of breakthroughs — radically better or entirely new aerospace concepts.”

NIAC provides $100,000 for nine months of research, with the possibility of another $500,000 for two more years if the results are promising.

Janson’s idea for the Brane Craft is definitely cutting-edge, and it could provide a solution to a difficult problem—how to get rid of all the orbital debris that could harm active spacecraft.

A graphic representation of the debris orbiting Earth, created with Aerospace’s Satellite Orbit Analysis Program. (Graphic: John Coggi)

A graphic representation of the debris orbiting Earth, created with Aerospace’s Satellite Orbit Analysis Program. (Graphic: John Coggi)

Janson had previously considered a concept called the Distributed Orbital Garbage Sweeper (DOGS). DOGS would consist of many small satellites sent to “fetch” individual pieces of orbiting debris and bring them down to burn up in the atmosphere. The problem was the cost.

“Sending conventional spacecraft, even CubeSats, to each of the thousands of 10-cm or larger debris objects for active deorbiting is prohibitively expensive,” Janson said.

Undaunted, Janson, who has worked in the field of small satellites for about 20 years, decided to go even smaller, at least in mass, with the Brane Craft.

To put the mass in perspective, a GPS IIF satellite weighs about 1500 kg, and a standard CubeSat is about 1 kg. The Brane Craft would only weigh about 50 grams.

The 30-micron-thick spacecraft would have a very high thrust-to-weight ratio, and would be capable of traveling long distances, which opens up other possibilities beyond just the removal of space debris.

“Brane Craft prospectors could land on any near-Earth asteroid, Phobos, Deimos, a wide variety of main belt asteroids, or orbit Mars or Venus, and return,” Janson said. “Brane Craft could access just about any orbit within cis-lunar space [between Earth and the moon] several times, with propellant to spare.”

It sounds great in theory, but obviously there are a number of engineering challenges associated with actually creating a flat spacecraft.

Janson has identified a number of current technologies that he believes could adapted for the Brane Craft, such as thin film solar cells and electrospray thrusters to propel the craft through space. To allow the Brane Craft to change shape, he is considering electrostatic polymers that will contract like muscles when a voltage is applied. He’ll also be investigating thin film transistors, super flat cameras, and more.

“This whole exercise is to see: can I get everything that I need for this spacecraft to fit on a thin sheet?” he said.

That’s what he will spend the next nine months researching. If successful, the Brane Craft project could provide a method of cleaning up the plethora of junk around the Earth, not to mention a really cool spacecraft with other potential uses.

According to NASA, “NIAC projects study innovative, technically credible, advanced concepts that could one day ‘change the possible’ in aerospace.”

The Brane Craft project aspires to do just that.

—Laura Johnson