Taking space travel to the next level is the ultimate tech test-bed
We got to the Moon, built the International Space Station (ISS)… so what’s next? Armstrong et al walked on the Moon 46 years ago, and since then we’ve all blindly assumed that inter-stellar travel can’t be far away – but it’s time to reign-in expectations and do some serious science.
Robotic missions might be buzzing around our neighbouring planets, and there’s talk ofsending man to Mars in the 2030s, but even that requires some serious new tech.
Launch systems that return their expensive first stages back to Earth to be re-used – possibly in a matter of hours – could be one of our generation’s biggest legacies to space travel. It may have landed too hard back in January 2015, and had a catastrophic failuresoon after launch in June 2015, but SpaceX appears to be on the cusp of successfully returning a Falcon 9 rocket to Earth (the demo rocket’s descent remains an awesome sight).
SpaceX’s immediate aim is to launch a Dragon capsule to the ISS safely – it’s already done that six times – and then land a Falcon 9 properly on a drone ship in the ocean for recovery and reuse. The next attempt is in mid-December 2015; if it succeeds we can all start dreaming about space travel again.
Next-gen journeys and deep-space robotic missions out of the solar system will require next-gen engines, but vague and unproven concepts like the perpetual motion machine, zero-point energy and cold fusion engines won’t get us very far. Cue solar electric rockets, the most efficient and cost-effective form of propulsion discovered so far. Nasa’s Solar Electric Propulsion (SEP) project uses just a tenth of the chemical propellants traditionally used by spacecraft. It has two versions of radiation-proof fold-out or ‘flexible blanket’ solar panels, and wants them tested in a low-Earth orbit by 2020.
Not enough? You wanted a WARP drive capable of light speed? Tough – Nasa calls it ‘simply imaginary’, although there is currently some chat about the physics-defying EM Drive, which uses a cavity filled with resonating microwaves to create propulsion without emissions. If it can get us to our neighbouring Alpha Centauri star system 4.3 lights years distant – some suggest it could – who cares it breaks the basic law of conservation of momentum?
Getting to a distant planet or moon is one thing; stopping in time is quite another. This is the game of atmospheric deceleration, and it reached the next level in June during Nasa’s ‘flying saucer’ test. Designed largely for Mars landings of the future, the Low-Density Supersonic Decelerator (LDSD) is the largest supersonic parachute ever built, with balloon-like pressure vessels that inflate around the spacecraft to slow it from Mach 3.5 to Mach 2 or lower.
It’s primarily for sending heavy cargo – twice as heavy as anything sent so far – safely to Mars in advance of more serous robotic, or manned, missions. However, it should also make landings on Martian mountains possible. See you at the top of Olympus Mons.
More people on the Moon might be pie in the sky for now, but it looks probable that astronauts will be sent to both an asteroid (in the 2020s) and to Mars (in the 2030s). That can only happen if new spacesuits are developed.
Why? Those used on the ISS, and by all astronauts, were designed for weightless environments, and while the Moon has just 16% the gravity of Earth, Mars has 62%. Moving around, bending and flexing suddenly becomes not only possible, but critical for survival. Cue Nasa’s Z-2 spacesuits, which allow just that, as well as using e-Ink, self-healing polymers and memory foam, and featuring sensors galore.
Sadly for those who want HD and 4K video streams from spacecraft, and ever-better scientific instruments, we’re running out of bandwidth in space, as the development of radio frequency transmissions hit a ceiling long ago. It’s now about 6Mbps. So why not use freakin’ lasers instead?
Developed by Nasa’s Jet Propulsion Laboratory, OPALS (Optical Payload for Lasercomm Science) is an optical communications technology based on the theory that laser beams are significantly narrower than RF, and so offer much more concentrated power. It’s already successfully beamed data at 50Mbps from the ISS to JPL’s Optical Communications Telescope Laboratory (OCTL) in Wrightwood, California. It’s early days, but the only restriction so far is line-of-sight. Nasa’s vast cloud awaits.
The fabric of space and time bends, so how do distant spacecraft – and even satellites close to Earth – keep precise-enough time to navigate? Now being developed by Nasa’s Jet Propulsion Laboratory, the Deep Space Atomic Clock (DSAC) will be 50 times more accurate than anything we have now. It uses radio frequencies to determine position, and will enable probes far from Earth to both navigate and collect data more precisely.
Just as clocks in GPS-based satellites are corrected daily to account for relativity – thank you, Einstein – so spacecraft will need to account for the distance they are from the DSAC, but it will give an accurate benchmark. Correct to a nanosecond every 10 days, and the culmination of 20 years’ work, a demonstration version of this mercury-ion atomic clock will orbit Earth from next year.
Weightlessness is bad for you. When astronauts lands in Kazakhstan after six months aboard the ISS, they’ve lost roughy 12% of their bone mass, and can’t even walk unassisted. If only we could artificially create gravity aboard long-period spacecraft, or at Lunar/Martian bases, as envisaged in every single sci-fi movie ever made.
A couple of years ago Nasa developed a US$3.7 billion concept called Nautilus-X for a module that could provide artificial gravity – initially attached to the ISS – by using a spinning centrifuge to generate enough G-force to create between 51-69% of Earth’s gravity. Nautilus-X is designed to be a deep space exploration vehicle that could get astronauts to Mars in a fit enough state to begin exploring immediately.
Future colonists of the Moon or Mars will have to live off the land; sending cargo and raw materials from Earth won’t be cost-effective. Cue robot-operated 3D printing (or ‘additive manufacturing’, to give it its less media-friendly name), with Lunar or Martian bases constructed using regolith from the surface as the only ‘ink’. Such a project was conceptualised recently by the European Space Agency and Foster+Partners architects.
It could also be mission-critical for the journey, too – having a machine shop in space to create spare parts may be a crucial capability for future deep space missions. Made In Space’s microgravity 3D printer is on the ISS.
Deep space navigation using less propellent is one thing, but a tech demo of a solar sail back in 2011 promised not only to clean up space trash orbiting Earth, but warn us of incoming solar storms. A solar sail demonstration mission, mooted by Nasa back in 2011, would gather enough electric energy from its 38m x 38m solar sail for a propellant-less thrust towards distant stars.
Its dwarfs Japan’s 14m x 14m IKAROS, which sailed all the way to Venus in 2010. Nicknamed Sunjammer, the technology could also be integrated into satellites to help them de-orbit once defunct. Nasa’s NanoSail-D – a nano-satellite fitted with a solar sail designed to bring down decommissioned satellites and space debris – spent 240 days in low-Earth orbit in 2011.
Human interstellar flight by 2112? There are those who want humans to travel to distant stars as soon as possible, and definitely within the next 100 years, but fear that our technology is developing far too slowly. Step forward 100 Year Starship, a pressure group that wants to help create enthusiasm for, and achievement in, science, technology, engineering and mathematics.
“100 Year Starship is about building the tools we need to travel to another star system in the next hundred years … we’re embarking on a journey across time and space,” says Dr. Mae Jemison, an ex-Space Shuttle astronaut, who leads 100 Year Starship. “If my language is dramatic, it is because this project is monumental … this is a global aspiration, and each step of the way, its progress will benefit life on Earth.”
“The Earth is the cradle of humanity,” said Konstantin Tsiolkovsky, the father of rocketry. “But mankind cannot stay in the cradle forever.” The only way out of the cradle is technology.