Crowd-funded stowaway to deploy 104 tiny satellites
BY STEPHEN CLARK
Posted: April 13, 2014
In a self-admitted act of desperation, Cornell University graduate student Zac Manchester in 2011 turned to Kickstarter, the online crowd-funding platform, to finance his money-starved project to deploy more than 100 thumbnail-sized satellites in orbit hundreds of miles above Earth.
The gamble worked, and 104 tiny printed circuit boards -- each a fully-functioning self-contained satellite -- are awaiting liftoff as soon as Monday on SpaceX's Falcon 9 rocket.
The launch is carrying 2.4 tons of supplies to the International Space Station inside a SpaceX-built Dragon commercial cargo vehicle, and five NASA-sponsored CubeSats are mounted on the Falcon 9's second stage as stowaways.
"It's been a wild ride the last couple of years, but so far its worked out," Manchester said. "My fingers are crossed for Monday that this all goes off, and hopefully we get some data back in a couple of weeks."
Manchester said he felt a mixture of anxiety and excitement, but he will have to wait an extra 16 days after the launch before learning the outcome of his experiment.
The tiny stamp-sized satellites, called Sprites by Manchester's team, are housed in four stacks inside a CubeSat mothership named KickSat, itself only measuring about the size of a loaf of bread.
KickSat's release from a carrier on-board the Falcon 9 rocket's upper stage about 16 minutes after liftoff Monday will trigger the start of a 16-day timer. If the launch occurs Monday, the 104 Sprites will be deployed from KickSat on April 30.
"They're packed in individual slots in the deployer on KickSat," Manchester said. "They're spring-loaded and when they get deployed, they're just released and they get flung out of the slots." An animation of the Sprite deployment is available on YouTube and is embedded below.
Animation of the KickSat deployment sequence. Video credit: KickSat
Each Sprite is a nearly flat 3.5-centimeter (1.4-inch) square just 3 millimeters thick.
"They weigh about 5 grams, and they have solar cells, a microcontroller, a radio transceiver and a couple of different sensors," Manchester said. "On different ones we have three-axis gyroscopes, three-axis magnetometers, various temperature sensors and stuff like that."
With the help of NASA's Ames Research Center, Manchester and a small cadre of helpers modified off-the-shelf printed circuit boards for the hazards of spaceflight.
Kickstarter contributors who pledged more than $1,000 to the KiskSat project could customize one of the Sprites.
"They have a prototype Sprite with sensors on it, along with a programming fixture and software so that they could program it themselves and come up with their own experiments to run on it," Manchester said. "A number of people did that and gave me their code, and then I loaded their code on the flight unit."
Several organizations, including the British Interplanetary Society, Kidz in Space, Astronauts4Hire and KGB Space Hoppers, sponsored "fleets" of Sprites on KickSat.
With a $300 donation, contributors could name one of the Sprites and specify the brief message its radio would transmit from orbit.
According to the project's Kickstarter website, KickSat received more than $74,000 from 315 backers through the online crowd-funding portal.
But that was just enough to fund construction of KickSat and the Sprites.
KickSat's launch would have cost more than $300,000, according to Manchester, but NASA selected KickSat for the space agency's CubeSat launch initiative, which offers flight opportunities to universities other educational institutions.
NASA's launch opportunity came free of charge to KickSat.
KickSat's mission will be short-lived, with each Sprite only expected to remain in orbit a few days once they are released from the CubeSat mothership.
The Sprites are too small to be reliably tracked by the U.S. Air Force's space surveillance network, which monitors all objects in orbit larger than 10 centimeters, or about the size of a baseball.
The poker chip-sized Sprites aboard KickSat are much smaller, but they should succumb to aerodynamic drag within days due to their low orbit less than 200 miles above Earth. At that altitude, the upper traces of Earth's atmosphere helps pull satellites down before they eventually burn up during re-entry.
The 16-day timer responsible for deploying KickSat's Sprites was added to the spacecraft to avoid the possibility of the little chips impacting the space station.
Manchester works on a research team at Cornell led by Mason Peck, a former NASA chief technologist, which has worked on chip-sized "femtosatellites" for nearly a decade. The objective is to reduce the cost of space missions and lay the groundwork for distributed networks of satellites which could be used for a variety of missions, including exploration and scientific research.
Three Sprite prototypes were flown to the International Space Station in 2011 as part of a materials science exposure platform, subjecting the chips to the perils of space before attempting to fly them on their own.
"We brought the technology to a point where we were fairly confident that it was viable and that it would work. The next step in doing it was actually flying them in space," Manchester said.
Organizers are eager for help in tracking the radio signals from the Sprite satellites after their deployment. Go to KickSat's website for more information on how to participate.
Follow Stephen Clark on Twitter: @StephenClark1.