ForewordThe following is Hackers In Space, as it appeared on page 21 of 2600 issue 29:3. This article is one of my personal favorites, since it deals with something that I have a great personal interest in: amateur space communication and technology.
As the cost of launches come down, and electronics get smaller and smaller, it's finally possible for groups other than world superpowers to get a spacecraft into orbit. This article presents a theoretical roadmap of sorts, which would take a dedicated and suitably funded group through the steps required to research and develop a small communications satellite.
The original ASCII text file for this document can be found in the "Text" section of the Downloads page.
IntroductionWhile those of us in the United States have managed to fight off large scale Internet censorship in the form of PIPA and SOPA (at least, for the time being), the battle to maintain an individual's unfettered access to the Internet is still raging all over the globe. Is it any wonder? With social networks becoming an increasingly indispensable tool for protesters and freedom fighters, the governments of many foreign countries are looking to actively censor, or even deactivate, the Internet at their discretion.
Now imagine plugging a device about the size of a standard USB WiFi adapter into your computer, setting up an antenna, and being able to receive news and information from orbiting satellites even when you can't get access to the Internet. But instead of these satellites being owned and operated by a government or corporation, imagine they were completely under the control of ordinary citizens. Such a network would be indispensable for combating corrupt governments, organizing rescue operations in areas stricken by natural disasters, and providing information to third world countries that don't have a telecommunications infrastructure. But, can it be done?
At Chaos Communication Camp 2011, a talk was given detailing a "modest" proposal for putting a hacker on the moon by 2034. While I can't say I am too optimistic about that particular goal (there is some debate if even NASA will be able to get anyone off this rock before then); the first phase of their plan, to build a free and globally accessible satellite communications network, is something completely different. With the rapid commercialization of space transport and operations, it's now possible for a group of individuals, using open source software and hardware, to construct, launch, and operate their own communications satellite; though certainly not easy.
First StepsWhen dealing with hardware intended for space flight, there is no such thing as being over-prepared. Anyone attempting to build a device and accompanying software destined for low Earth orbit (LEO) would be wise to start a bit closer to the surface of the Earth, by way of a high altitude balloon. Using readily available weather balloons, it's possible to send a small payload up to 100,000 feet (30 km). At this altitude, the sky turns black and the temperatures can drop down to nearly -100 F (-73 C), an excellent dress rehearsal for a space mission.
Operating a craft in near-space, generally considered to be anywhere between 65,000 feet (20 km) and 350,000 feet (107 km), demands many of the same design paradigms of a true spacecraft: reliability, redundancy, energy efficiency, thermal protection, mass and dimensional constraints, etc. Operating such a craft would also require the ability to track and effectively communicate with a high altitude object, one of the most important aspects of creating a practical communications network. In fact, the Hackerspace Global Grid is a project dedicated to just that subject, the tracking and identification of satellites via open source software and hardware. You can't talk to something you can't find, so this subject is getting a lot of research and development now in preparation of future projects.
While you'll never construct a global communication network with balloons alone, they may have a future in temporary or emergency networks. The LVL1 hackerspace in Louisville, Kentucky is working on the White Star Balloon project, a self-ballasting weather balloon capable of maintaining its altitude and staying airborne for days at a time. While LVL1's goal with White Star is to send the balloon across the Atlantic Ocean via the jet stream, it's not unreasonable to imagine a similarly designed balloon equipped with some type of propulsion system being able to maintain its position (roughly) over an area for extended periods of time. Being able to place a balloon over a target area for use in communications or even surveillance has some very obvious uses. Incidentally, the US military is currently experimenting with this very concept using manned and unmanned balloons.
Getting Into SpaceBuilding a high altitude balloon is certainly a challenge, but not outside the grasp of even a clever high school student. It's a good demonstration, but it's a far cry from building and launching a proper satellite. So what now? How do you actually get something into space if you aren't a world superpower?
Not that long ago, you didn't. It just wasn't happening. But as commercial spaceflight started to emerge as a viable enterprise, a new class of satellite quickly started to gain popularity: the CubeSat. CubeSats are miniature satellites, sometimes referred to as picosats or nanosats, which adhere to specifications written by the California Polytechnic State University and Stanford University. CubeSats are 10x10x10 cm cubes with a mass of 1 kg, scalable along one axis up to 3 cubes. This allows for a satellite (known in this configuration as a 3U CubeSat) with a maximum size of 10x10x30 cm and a maximum mass of 3 kg. The mass and dimensional constraints are tight, but with ever smaller components and manufacturing techniques, it should be within the capabilities of a well equipped hackerspace.
Of course the next question is: how much does it really cost to build and launch a CubeSat? There are a lot of variables involved here, from the size of the satellite to the orbit it's placed in. A realistic estimate for getting a 1U CubeSat (a single 10x10x10 cm cube) into orbit would likely be around $80,000 to $100,000 USD, though depending on who you talk to the number can be as low as $40,000. While $100,000 is surely a lot of money for us in the "99%", it's not an unreachable goal. Consider that the TikTok project managed to raise $942,578 on Kickstarter...and its a watchband for the iPod Nano. If the hacker community could raise that much money, a fleet of communication satellites would be well within the budget.
For the hacker on an even tighter budget, Interorbital Systems plans on beginning launches for their "TubeSats" this year. The TubeSat is advertised as "the low-cost alternative to the CubeSat", costing only $8,000 for the construction kit, including the launch. The steep discount does come with a penalty however, as the TubeSat offers only three-quarters the total mass of the 1U CubeSat, and is placed in an orbit which will decay after a month or so. Still, there's something to be said for being able to build and launch your own personal satellite for the cost of a decent used car.
Ears To The SkyA lot of people seem to be under the impression that communication with satellites requires a 10 foot wide satellite dish and a room full of radios. In reality, you can receive the downlink of low altitude satellites with nothing more than a handheld scanner and a simple "rubber duck" antenna. Naturally this isn't an ideal solution, and a more permanent installation with motorized high gain antennas would get much better results, but it does give you an idea of what's possible in a pinch.
Another common misconception is that satellite communication requires a license. While transmitting to an orbiting satellite would require an amateur radio license from your government of choice, simply receiving broadcasts on the common satellite bands can be done by anyone with the appropriate equipment. Naturally, this means that communication with our theoretical hacker satellite network would be one-way for unlicensed individuals, but that really isn't a problem. The immediate goal of such a project would be to spread news and information to people who would otherwise be cut off from the world, so in that case it would be enough to receive a downlink of the latest pertinent information. Of course, anyone with the appropriate license and adequate equipment could use the satellite network in a bi-directional fashion as well, so both use cases could be served simultaneously.
With recent advancements in Software Defined Radio (SDR), you don't even need a traditional radio to receive broadcasts anymore. Products like the FUNcube dongle are low cost SDR devices specifically designed for amateur satellite communication. Coming in at under $300 USD and controlled by freely available open source software, SDR devices like this bring satellite communication within reach of even the most modestly funded hackerspaces or groups of individuals. As the market for satellite-oriented SDRs grows, we will see those prices come down even farther; to the point that within a few years a radio capable of receiving satellite transmissions might not cost much more than WiFi hardware.
Reasonable ExpectationsWith talk of satellite ground stations and launching home-built spacecraft, it's easy to get carried away. A look at any of the mainstream media coverage of projects like the Hackerspace Global Grid will give you a good idea of how easily the imagination wanders (or runs) when taking about anything to do with space.
The major thing to understand is that nobody is suggesting a "parallel Internet". That was an idea the media glommed onto almost immediately, but it's wildly impractical. Establishing a meaningful TCP/IP connection to an amateur satellite would be a challenge for even a well-equipped ham radio operator, so the idea that this could be a service offered to the masses is out of the question right now.
Most likely, the early versions of a hacker satellite network would only be able to broadcast simple text messages. Think of an orbiting serial terminal, and you'll have a pretty good idea of what's possible. Licensed radio operators with the appropriate equipment could upload the message to be broadcast, and the satellites would then repeat it to anyone who cares to listen until they receive new instructions.
Perhaps not as exciting and glamorous as some people might like, but it's a start. Such a system could be invaluable for individuals whose government censors (or cuts off) their Internet access or in emergency situations.
ConclusionIt'll be quite some time before we can surf the web on our own hacker-built satellite ISP. But with the proper research, funding, and skill, it's not unreasonable to think we could see low cost receivers pulling down data from civilian built satellites within the next two years; assuming there are enough people motivated to make it happen.
As John F. Kennedy said of the Apollo program in 1962, we do these things "not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills".