Harvest the Sun — From Space

By O. Glenn Smith, a former manager of science and applications experiments for the International Space Station at NASA’s Johnson Space Center (THE NEW YORK TIMES, 22/07/08):

As we face $4.50 a gallon gas, we also know that alternative energy sources — coal, oil shale, ethanol, wind and ground-based solar — are either of limited potential, very expensive, require huge energy storage systems or harm the environment. There is, however, one potential future energy source that is environmentally friendly, has essentially unlimited potential and can be cost competitive with any renewable source: space solar power.

Science fiction? Actually, no — the technology already exists. A space solar power system would involve building large solar energy collectors in orbit around the Earth. These panels would collect far more energy than land-based units, which are hampered by weather, low angles of the sun in northern climes and, of course, the darkness of night.

Once collected, the solar energy would be safely beamed to Earth via wireless radio transmission, where it would be received by antennas near cities and other places where large amounts of power are used. The received energy would then be converted to electric power for distribution over the existing grid. Government scientists have projected that the cost of electric power generation from such a system could be as low as 8 to 10 cents per kilowatt-hour, which is within the range of what consumers pay now.

In terms of cost effectiveness, the two stumbling blocks for space solar power have been the expense of launching the collectors and the efficiency of their solar cells. Fortunately, the recent development of thinner, lighter and much higher efficiency solar cells promises to make sending them into space less expensive and return of energy much greater.

Much of the progress has come in the private sector. Companies like Space Exploration Technologies and Orbital Sciences, working in conjunction with NASA’s public-private Commercial Orbital Transportation Services initiative, have been developing the capacity for very low cost launchings to the International Space Station. This same technology could be adapted to sending up a solar power satellite system.

Still, because building the first operational space solar power system will be very costly, a practical first step would be to conduct a test using the International Space Station as a “construction shack” to house the astronauts and equipment. The station’s existing solar panels could be used for the demonstration project, and its robotic manipulator arms could assemble the large transmitting antenna. While the station’s location in orbit would permit only intermittent transmission of power back to Earth, a successful test would serve as what scientists call “proof of concept.”

Over the past 15 years, Americans have invested more than $100 billion, directly and indirectly, on the space station and supporting shuttle flights. With an energy crisis deepening, it’s time to begin to develop a huge return on that investment. (And for those who worry that science would lose out to economics, there’s no reason that work on space solar power couldn’t go hand in hand with work toward a manned mission to Mars, advanced propulsion systems and other priorities of the space station.)

In fact, in a time of some skepticism about the utility of our space program, NASA should realize that the American public would be inspired by our astronauts working in space to meet critical energy needs here on Earth.

Britain should be leading the search for life on Mars

By Colin Pillinger, the principle investigator for the Beagle 2 Mars project, part of the European Space Agency’s 2003 Mars Express mission (THE GUARDIAN, 28/05/08):

The triumphant landing of the Phoenix craft on Mars is a tribute to the team of engineers at the Jet Propulsion Laboratory in California – one of whom, Peter Smith, was a colleague of mine on the Beagle 2 mission to the planet in 2003. Using the Mars reconnaissance orbiter, they selected an excellent place to land, and were able to use thrusters to hit the spot safely and softly.

But it’s also a tribute to the perseverance of Nasa, which has launched missions to the planet every 26 months. They have built at least 23 orbiting spacecraft, and have now had three successful landings. They’ve had a policy of following the water, the essential element of life. We have known for 200 years that Mars has polar caps, which could have contained a mixture of water and carbon dioxide. Nasa has seen, from orbit, where the most likely places are for water to be found; they have also identified minerals that appear to have been deposited from water. But though the orbiters can suggest water is present – from radar signals and an abundance of hydrogen – they haven’t been able to identify water unambiguously. That’s why Nasa has had to send a lander.

It is, though, very difficult to steer a craft towards the poles – orbiting around the equator is far easier – so the Phoenix mission has landed at a site which is, in relative terms, as far north as Greenland. The pictures beamed back so far show no obvious signs of snow or ice, but the craft’s robotic arm can reach up to two metres, and dig a trench, in the hope that there is permafrost to be found below the surface.

I’m 99% certain they will find water. And, if so, they will also be able to identify the salts within it, and whether they are suitable for micro-organisms to live on. They’ll be able to clearly answer whether this place could be suitable for life to evolve. They are also going to check for organic molecules. I really hope they find them. Though we have found carbon on meteorites on earth, nobody has ever discovered a single atom of carbon on Mars – other than the carbon dioxide in the atmosphere.

And this is where the mission’s limitations could set in. The measuring equipment they have on board won’t be able to tell if any carbon is biological (ie, living carbon) or simply the debris of meteorites that may have crashed on the planet.

I can’t help feeling frustrated, because the Beagle 2 mission would have been able to make this distinction. The Phoenix design is based on a craft that crash-landed in 1999, and building Beagle technology into this mission simply wasn’t feasible in the planning time they had. After the 1999 loss, Nasa simply shrugged their shoulders, learned their lessons, and got on with the next mission. With Beagle, the British government and the European Space Agency sighed a collective “oh dear,” and stopped there. There was no reason why another Beagle mission couldn’t have worked, but they seemed to lose the will to go on.

As it is, the next European mission will not be until 2015, by which time it may feel out of date (and there’s a chance it may not happen). It will cost €1.5bn, six times more than the current Nasa mission. That’s why I get frustrated, because it proves this is not a question of money: a Beagle mission would have been even cheaper than Nasa’s, so the ESA could easily have tried again.

We had enough time to have launched another mission last year, ahead of Nasa, and with instruments capable of identifying every carbon atom in all its forms – to detect whether life exists, or has ever existed.

We could have solved the question all humanity really wants answered: are we alone? If we could show that life on Earth was not unique, the discovery would be on a par with Copernicus saying the Earth went round the sun. It would bring a fundamental shift in the way we all think about ourselves.

Nasa have another spacecraft, set to launch in 2009, that will be carrying a much more sophisticated instrument on a car-sized, roving module. With their findings from Phoenix, they will be able to choose a suitable landing spot and give themselves a much better chance of answering whether there is, or was, life on Mars. These are big stakes. If a British mission had made this breakthrough, it would have inspired our whole country: we’d have kids wanting to take up science, which is what so many people want; and we would have sent a message to the world that Britain, once the dominant power over the seas, is now a space-faring nation.

As it is, Britain and Europe chose shortsightedness over scientific endeavour. Their inaction must go down as a huge missed opportunity.