Small Satellites & Small Launchers | Pair of Upgraded PhoneSats Set To Begin Yearlong Mission
WASHINGTON — Launching later this year as ride-alongs on military and NASA missions, two upgraded PhoneSats — cubesats built around the core electronics of consumer smartphones — are beginning to look more “sat” and less “phone.”
The two spacecraft, which excluding the salaries of the NASA engineers who conceived and built them cost around $10,000 apiece, have moved beyond the “smartphone-in-a-box” design that was the hallmark of their two earliest predecessors.
“We don’t have the screen and the case and all that other stuff that we had on PhoneSat 1.0,” said Bruce Yost, manager of the Small Spacecraft Technology Program at NASA’s Ames Research Center in Mountain View, Calif. “We took just the guts of it out of the phone and repackaged it with some other sensors.”
The two original PhoneSats — plus a third that more closely resembled the craft scheduled to launch later this year — flew in space for six days after being blasted to an orbit about 250 kilometers up during the successful debut of Orbital Sciences Corp.’s Antares rocket on April 21.
The next in the series, PhoneSat 2.4 and PhoneSat 2.5, are respectively scheduled to launch aboard the Air Force’s Operationally Responsive Space (ORS)-3 mission in November and on a cargo resupply run Space Exploration Technologies Corp. is making to the international space station in December. NASA’s Cubesat Launch Initiative brokered the rides.
Each second-generation PhoneSat is a 1.5-unit cubesat, slightly larger than the single-unit cubesats used for the PhoneSat 1.0 models. A standard cubesat measures 10 centimeters on a side and weighs about 1 kilogram.
In every way, the next two PhoneSat flights will be more like routine satellite missions than the first three, Yost said.
PhoneSats 2.4 and 2.5 will fly to an orbit about 350 kilometers above the Earth where — with the assistance of solar cells, reaction control wheels, after-market batteries, inertial measurement units and ultra-high-frequency radios — they will remain for a year.
The ground component of the mission has also become more sophisticated.
The first PhoneSat mission relied on a network of amateur radio operators to collect signals from the cubesats after they were deployed by Antares. Amateur listeners then collected PhoneSat data packets and forwarded them to NASA, which eventually published the results — a series of grainy, but recognizable, photos of the Earth captured with the stock cameras of the Google Nexus handsets that powered the PhoneSats.
“That’s kind of the crowdsourced way to do it,” Yost said. “It’s low bandwidth, but it has a lot of coverage from people all over the world.”
Data gathering and processing for the upcoming PhoneSat mission, on the other hand, will be run by California’s Santa Clara University near Ames’ main campus.
PhoneSat was a creation of the Small Satellite Technology Program, which is overseen from NASA headquarters by Andrew Petro. The program got about $15 million for 2012 and, because of its relatively low level of funding, was not particularly hard hit by the across-the-board, sequestration cut NASA absorbed for 2013, Petro said in an Aug. 7 interview.
The program Petro administers was created in 2011, around the time NASA resurrected the Office of the Chief Technologist to oversee a spate of experimental space technology programs now managed under the Science Technology Mission Directorate, which was stood up in February.
One of the “big nine” programs in the new mission directorate, the ultimate goal of the PhoneSat project is to produce something that could be “tied into other projects,” Petro said.
That could take a while.
Yost said the primary advantage of “using these phones for satellite brains” is that it allows NASA to design small spacecraft using cheap, thoroughly tested, powerful components that would bring part costs down to the realm of “tens of thousands of dollars, versus millions.”
“They’ve been tested in some relatively extreme environments on the ground [and] they’re very powerful,” Yost said. “There’s a lot of processing power and memory on these small devices, compared with what we’ve been traditionally flying in spacecraft in our recent history.”
If the price of a mission comes down thanks to off-the-shelf parts, that could encourage more risk-taking on the part of mission planners. However, it would also mean coming up with a way to do a scientific mission with many small satellites instead of one large one.
To that end, Ames is already gearing up for work on a swarm of PhoneSats, which will launch in 2014 as part of NASA’s Edison Demonstration of Smallsat Networks, or EDSN, program.
“We want to fly eight spacecraft with the phones as their core processors and brains and we want to try to do some communications experiments on how you manage information on a distributed network,” Yost said. “The goal is for these spacecraft to talk to each other, and then one of them will talk to the ground as a relay.”
That mission, once again, is being undertaken in partnership with the Air Force, Yost said.