I once stood on a hillside in northern England watching a group of enthusiasts attempting to launch a rocket. A small crowd gathered in the rain as we waited for the countdown. Nothing happened for a while…and then nothing happened again…and then we all went home. Anyone who ever turned up for a Shuttle launch will be familiar with the experience.
Even small rockets are hard to build and even harder to launch successfully. After all, it took Wernher Von Braun the resources of the Nazi war machine and thousands of slave labourers to successfully develop the V2, and the equivalent of almost $100 billion (in today’s money) to put men on the Moon. Even now, it costs at least $12 million to charter the cheapest launch vehicle to orbit.
Rockets are hard. So how can us enthusiasts ever get to launch anything? Do not despair, here at BBC Future we’ve been investigating the options for you and it turns out you do not have to have the resources of Richard Branson or Elon Musk to get something into space. And to prove it, we even have launch plans of our own.
Floating in space
One of the least expensive options to start your career as a rocket scientists is to blow up a balloon. A very big balloon. Amateur clubs, such as the Cambridge University Spaceflight society in the UK, fly helium-filled meteorological balloons up to an altitude of 30km (19 miles) with payloads as varied as teddy bears, cameras, computers and scientific instruments. They can even be used to send a man… well, a Lego man. The recent launch of a Lego Man into space by two Canadian teenagers has become a big hit on YouTube.
The technology involved in flying a legonaut or cosmoteddy is relatively simple – inflate your balloon, attach payload and watch it go. The trick is getting them back. As your balloon rises through the atmosphere, the air pressure decreases and the balloon expands. There comes a point where the latex fabric is stretched so thin, that it bursts and the payload (toy) is released. As long as you’ve got a parachute between the payload and the balloon, your toy of choice should float safely back to Earth. If you’ve put a tracking device on board, you might even be able to find it.
Here’s the important bit: if you’re planning on launching a weather balloon you will almost certainly need permission from the aviation authorities. The Cambridge club, for instance, has a permanent licence but still needs to call air traffic control before launch. Balloons and planes don’t mix.
The images sent back of the curvature of the Earth by Lego Man are stunning and you can certainly see the blackness of space. But the fact is, weather balloons don’t go high enough and are still well within the atmosphere. Only one tiny step for Lego-kind I’m afraid. So how do you go higher?
“Typically when you want to go into space, you launch a rocket,” says Edward Cunningham, a third year physics undergraduate at Cambridge. “To launch a rocket from the ground requires lots and lots of thrust, quite a large rocket and lots of money.” The challenge is not just overcoming gravity but air resistance. “So, what we’ve been thinking,” he says, “is whether we can get past all this atmosphere and then launch a rocket. So, we’re building a rockoon.”
The concept of a rockoon (from rocket and balloon, if you’ve not worked it out) is almost as old as modern rocketry and was conceived in the 1940s by the US military during the development of ballistic missiles. The Cambridge students hope to fly rockoons in a parabola up to 100 km (62 miles) – well into space – at a cost of less than $1500.
“What you end up with is your large helium balloon with your rocket suspended beneath it,” Cunningham explains. “Then, before the balloon bursts, you send a command to launch the rocket and it’ll penetrate the balloon and, if all the calculations work, get into space.”
All well and good. But to get into orbit you need a lot more power and a good deal more cash.
Until recently, your best bet for flying a spacecraft in orbit was to build a CubeSat. These miniaturised satellites are based on a 10cm (4 inches) cube and usually “piggyback” on other satellite launches to keep costs down. You can buy kits for CubeSats, which are increasingly popular amongst academic groups, and Nasa even has a programme to launch some of them for free. However the price of putting a mission together, at upwards of $30,000 (excluding launch), is still well beyond most of us. Fortunately Zac Manchester, from Cornell University in New York, has designed a way for lots of people to get onboard a CubeSat.
He has plans to launch an alternative, smaller spacecraft called a sprite. Little bigger than a thumbnail, these are as simple as spacecraft get – consisting of a few solar cells, a microprocessor and a transmitter. They are the modern equivalent of a beeping Sputnik. Zac’s mission packs multiple sprites into a single CubeSat. Once in orbit the tiny craft will spring from their mothership to orbit the earth on their own (over a few weeks their orbit will decay so they burn up in the atmosphere). What’s really cool about this scheme is the price: each sprite costs just $300. The whole project has been funded through donations and anyone who pledged the full $300 gets a sprite to call their own.
“It’s not just that people can say ‘I own 2% of this big monolithic satellite,’” says Manchester. “It’s ‘I own this little thing in space that has my name on it, it’s mine’. I think that personal ownership aspect of it makes it very exciting.” So exciting, that he’s captured the imagination of the worlds’ space geeks and sold the lot.
Over the next few months, the Cornell team will be building the sprites and putting the satellite together. Here at Space Station, we’ll be following their progress with a vested interest because we’ve managed to secure one of the last remaining sprites on your behalf. We plan to follow the project in more detail as we get closer to launch date. But if all goes to plan, this time next year, readers of BBC Future and listeners to my podcast will have a satellite to call their own. And it won’t cost you a cent.