Two birds flew proudly on 29 September as humans took two more steps in space. SpaceX's Falcon 9 rocket took a step forward towards the goal of reusability which would make the journey into orbit much simpler and cheaper. Orbital Sciences' Cygnus capsule docked successfully with the International Space Station (ISS), delivering a payload of hundreds of kilograms of supplies.
Together the two developments show how the private companies are moving forward towards the dream of shuutle operations into orbit. If the cost of carrying up cargo can be brought down, then space station can become a true gateway to the Solar System.
Last year SpaceX's Dragon C2 capsule became the first privately operated spacecraft to dock with the ISS. With Orbital now achieving the same capability with Cygnus, the new private sector model is becoming consolidated.
The challenge for them both is bring down costs of getting up into orbit, and the aim is to shift from the now-familiar throwaway approach of dropping first-stage rockets into sea and oblivion.
So for its latest operation, which involved taking a Canadian communications and weather satellite into orbit, SpaceX left some fuel in the tanks of the first stage of its Falcon 9 heavy lifter rocket. The aim was to steer the first stage back to earth for future reuse.
The re-ignition worked and some manoeuvres were carried out, although a second re-ignition put the rocket into a spin and caused it to crash. But the principle has been established - it is indeed technically possible to get the first stage under control and save it.
To the Moon and Mars
Up till now the focus of space development has been on long-distance firing of rockets from the earth, and the sheer cost and complexity of this has meant that even a return to the Moon has not been possible. But now attention is shifting to cutting down the cost of getting into orbit around the earth. If we can get into orbit cheaply, then from there it will be easier to assemble spacecraft for longer-distance missions to the Moon and Mars.
And Mars is where SpaceX's Elon Musk wants to go. He set up the California-based company in order to develop the necessary technology, including the Dragon spacecraft and the Falcon 9 rocket that's taken it up into orbit.
The Dragon and Cygnus missions are the latest in a series of flight demonstrations for NASA’s private sector COTS programme – the acronym stands for Commercial Orbital Transfer Services.
The Dragon capsule is reusable, and can carry up to seven astronauts, or up to 6000 kilograms of cargo. You can see how it is structured.
The two-stage Falcon 9 rocket is fuelled by a combination of liquid oxygen and kerosene, and the tank walls are made of an aluminium-lithium alloy. The development of a recovery system will significantly bring down operating costs.
The challenge of keeping control of costs is one that the founder of Space X, Elon Musk, has taken head on. The charge to NASA for each of the 12 planned Dragon missions is fixed by contract, and covers everything needed. ‘If there are cost overruns, SpaceX will cover the difference,’ he says. Musk quotes a Chinese government official who confirms that SpaceX have the lowest operating prices in the world. But, he emphasises, this is just the start.
‘SpaceX intends to make far more dramatic reductions in price in the long term when full launch vehicle reusability is achieved.’
He’s also kept control on development costs. The Falcon 9 launch vehicle was developed from a blank sheet of paper to its first launch for just over $300 million dollars. The Dragon spacecraft was taken through a similar process for around the same amount.
A dream of a red planet
Elon Musk is a physicist who is the co-founder of PayPal and also of Tesla Motors, where he led development of the Tesla Roadster. He is also chairman of the photovoltaics company Solar City. His aim in setting up SpaceX was to get to Mars, and he had some capital to invest when he sold PayPal for $1.5 billion. But when he heard that the launch costs of sending one spacecraft to Mars would be two and a half times the cost of building it, he reckoned that something was wrong with the economics of space. So he decided to focus first at a key part of the problem – the high cost of taking up a capsule into earth orbit.
The first step was to find a chief engineer who could design a better type of rocket, so he contacted the Reaction Research Society, America’s oldest rocketry club, founded in the 1940s. The RRS told him about Tom Mueller, one of the world’s foremost rocket engine designers who was at the time in charge of liquid rocket engine activity at TRW, the aerospace company which had built several Pioneer spacecraft and the descent engine for the Apollo lunar lander. In his spare time Mueller was putting the finishing touches on his own liquid-fuel rocket engine, which would be the largest amateur-built of its type in the world. Elon Musk went to visit Tom Mueller and asked just one question: ‘Can you build something bigger?’
‘Mueller never fired that engine,’ says the account in the magazine Popular Mechanics. ‘Instead, he took up Musk’s offer to join the nascent private space venture.’
The docking with the ISS is only part of the story. SpaceX's rocket, the Falcon 9-Heavy, is the most powerful rocket since the Apollo era. It's able to put more than 53 tonnes of payload into a low-earth orbit – that’s more than a fully loaded Boeing 737 with passengers, luggage and fuel.
SpaceX is also collaborating with Stratolaunch Systems in the development of an air-launched system to carry spacecraft into orbit. The rocket to carry the spacecraft will be a development of the Falcon 9, and the carrier aircraft will be developed by Scaled Composites, Burt Rutan’s company which produced SpaceShipOne for the Ansari Prize and SpaceShipTwo for Virgin Galactic. Stratolaunch reunites Rutan and Paul G. Allen, the Microsoft cofounder who funded the original SpaceShipOne development.