Leonard David's INSIDE OUTER SPACE

Image credit: University of Arizona/CatSat Project

In outer space can you hear the sound from ballooning expectations?

That “Noise of Summer” liftoff of Firefly’s launcher on July 3 from Vandenberg Space Force Base was loaded with eight CubeSats under NASA’s CubeSat Launch Initiative (CSLI).

One of the mini-spacecraft is a technology demonstration of a novel inflatable antenna for high-speed communications.

Called CatSat, this University of Arizona payload is showcasing inflatable technology, a deployable antenna consisting of a Mylar balloon.

CatSat’s central body is roughly the size of a large cereal box.

Image credit: Firefly Aerospace

Half-and-half

The front half of the balloon is transparent, allowing microwaves to pass through. The back half of the balloon is aluminized, creating a reflecting antenna.

After reaching low Earth orbit, CatSat’s antenna is slated to deploy and inflate to a diameter of just over one-and-a-half feet.

CatSat’s demonstration will be to transmit high-definition Earth photos at high-speed. The CubeSat will also relay data about the structure of the Earth’s ionosphere, gathered by listening-in to thousands of beacons from ground-based ham radio stations.

That’s a drag

CatSat will use a whip antenna to study Earth’s upper atmosphere before deploying its beachball-looking antenna.        

“Once the inflatable antenna is deployed, it will increase drag,” said Shae Henley, the CatSat team’s lead integration and testing engineer at the University of Arizona.

“Even though we’re in low Earth orbit,” Henley said in a university statement, “there’s still some residual atmosphere in that part of space. That’s why there will still be drag due to the inflatable antenna’s larger size. So, we want to get some good ionospheric data beforehand.”

Size constraints

CatSat is a student-run project involving NASA’s Space Technology Mission Directorate, Freefall Aerospace, the University of Arizona, and Rincon Research Corporation in Tucson, Arizona. 

Artwork depicts CatSat in Earth orbit, with its inflatable, beachball-like antenna deployed.
Image credit: University of Arizona/CatSat Project

The Large Balloon Reflector concept, said Chris Walker, a UArizona professor of astronomy and principal investigator of the CatSat project, is an inflatable technology that creates large collecting apertures that weigh a fraction of today’s deployable antennas.

The Large Balloon Reflector was an early-stage study developed through NASA’s Innovative Advanced Concepts (NIAC) program.

Walker is the father of the inflatable antenna concept used by CatSat.

The compactness of CubeSats has its drawbacks, pointed out Henley.

“But while the technology can be shrunk down with miniaturized components, the size of the antenna can’t break the laws of physics, and therefore there are size constraints,” Henley said in a university press statement. “Our solution to that challenge is an inflatable antenna.”

Future concept goes the lunar distance. Image credit: Freefall Aerospace

Moon, Mars designs

The CatSat team is looking into what they could do next with CubeSats, beyond Earth orbit.

One idea involves a CubeSat orbiting the Moon (LunaCat). Another design would use a CubeSat as a data transmitter for a Mars mission (MarsCat).

Fortifying those future plans, last May the team received a 3U CubeSat valued at  about $500,000 from GOMspace North America, who donated the spacecraft to the CatSat team for a future mission. CatSat itself uses a GOMspace spacecraft bus.

“CatSat is definitely more Earth focused,” Henley said. “But an inflatable antenna has a lot of potential, even for deep space and longer, farther missions.”