Q What does STRaND stand for?
Surrey Training, Research, and Nanosatellite Demonstrator
Q What model is the phone?
It's a Google Nexus One. It was chosen because it runs on the user-friendly Android operating system and was cheap and easily available when the project kicked off.
Q Is the whole phone flying, or just components from it?
The whole phone is flying - it hasn't been stripped down. It's mounted against one of the panels, with the phone camera peeping out through a "porthole".
Q What will the phone do?
The phone will:
- Run a number of Apps - some collecting scientific data, some just for fun and outreach
- Take photos of the Earth using its own camera
- Once all the satellite's own operating systems have been checked out, we will transfer some key system functions over to the phone's components to take control and operate the satellite in orbit.
Q Are you using the built-in phone GPS?
No. Terrestial GPS units cut out and stop working about 60,000 ft so on STRaND-1 we are including an SGR-05U
, which is a very small standard space-rated GPS unit built by SSTL.
Q Can you upload Apps to the phone in orbit?
Q How much does STRaND-1 weigh, how big is it?
STRaND-1 is a 3U CubeSat (30cm x 10cm) and weighs 3.5kg
Q Where will the satellite be operated from?
The groundstation is at The Surrey Space Centre at the University of Surrey.
Q How long did it take to build?
The STRaND-1 project kicked off in 2011, but the actual build and text phase started in October 2012 - about 3 months.
Q As well as the phone, is STRaND-1 flying any new technologies?
- a new propulsion system called WARP DRiVE (Water-Alcohol Resistojet Propulsion Deorbit Re-entry Velocity Experiment)
- Eight pulsed plasma Thrusters
- a high speed linux based data processor
- 3D printed part (two structural reinforcements to hold the lenses in place)
Q Have you considered the radiation environment?
Absolutely. SSTL has heritage in using COTS components in space and intimately understands how to shield sensitive equipment from the radiation environment in space. We are also performing radiation tests on the model of the phone on the ground before launch so that we know what to expect from the phone in space.
Q How are you stopping the phone battery from getting too cold?
The onboard computer will monitor the temperature of the phone battery. If it sees it is getting too cold, it will trigger a processor intensive program to run on the mobile phone, which will warm it up.
Q Haven't people already put phones into space?
A number of groups have put smartphones onto high altitude helium-filled weather balloons. These are exciting experiments in themselves that fly very high in the atmosphere, but atmosphere is the key word!
NASA Ames have even put them on top of sub-orbital sounding rockets.
Smartphones have also floated inside the shuttle and international space station, but they were operated by humans, in air, and so these were not subjected to the harshness of space.
An interesting Japanese mission called Cute-1.7 was launched in 2006 which used circuit boards taken from two PDAs.
NASA has a phonesat mission in the pipeline.
Mobile phone technology has made giant leaps in the last 5 years, and no-one has flown a full mobile phone in what we would call "proper" space...yet!
Q How much does it cost?
The phone itself costs less than £350. The STRaND-1 satellite as a whole will cost only slightly more than a high-end family car.
Q. Can I track STRaND-1 in orbit?
Yes. STRaND-1 carries an amateur radion 9600 bps AX.25 packet radio downlink on 437.568 MHz. Frequency and telemetry information for STRaND-1 is provided on the AMSAT-UK
Q Isn't this just adding more space junk?
As a responsible space operator we take our space debris commitments very seriously. It's worth noting that the orbits of most nanosats degrade quicker than larger satellites because they have a higher surface area to mass ratio, and often come down and burn up in the atmosphere within the 25 year international guidelines. But on top of this, we're equipping STRaND-1 with two types of thruster so that when we've completed our mission objectives we can lower our orbit altitude as much as possible to speed up the orbit degradation.
Q Do Google know you are doing this?
Yes they do, and they think it's a cool idea.