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Yuri Milner

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Space Dreams

Some other contender for the title of Curmudgeon of the Year may emerge before the end of December, but at the moment it looks like Mark McCaughrean, senior adviser for science and exploration at the European Space Agency, will win in a walk. When Elon Musk unveiled some details of his plan to create a large human settlement on Mars in the journal New Space in June, McCaughrean tweeted as follows.

“It’s a wild-eyed investment pitch, pumped up by the enthusiasm of fanboys brought up on comic-book sci-fi, wrapped in evangelism of saving humanity from itself and the problems we’ve brought on this planet, a kind of modern-day manifest destiny,” he said, waving his stick angrily in the air. (I made that last bit up.)

“I’m less concerned about making humans a multi-planetary species than I am about making the Earth a sustainable multi-species planet, before we go gadding off colonising the solar system,” he continued. Harrumph. Science journalists always have the phone numbers of grumps like this, because every science story has to have a quote from somebody saying that it’s a bad idea – but it does sound like McCaughrean is in the wrong job.

I’m writing this now, although McCaughrean’s rant happened almost two months ago, because I’m currently on Baffin Island, just about the least hospitable place on Earth that has sustained a long-term human presence.

The ancestors of the present Inuit inhabitants arrived here a thousand years ago without even metal tools, and it occurs to me that if they could make a go of it here, then people with currently available technologies can probably make a go of settling Mars.

The red planet gets much colder than Baffin, its air is not breathable, the water is frozen in the soil, and the lack of a magnetic field lets hard radiation get through to the surface during solar storms, but a human colony on Mars is not impossible.

It may never be the million-strong settlement that Musk imagines a century from now, but he never said he was going to build that himself. What he is building is an Interplanetary Transport System (ITS) that would get people there for as little as $200,000 each. Then just stand back and watch as people with ideas about what could be done on Mars put their money down.

Musk is already building and testing elements of the ITS. He has a brilliant record as a high-tech entrepreneur (the Tesla electric car and the existing generation of Space-X launch vehicles). He has already successfully landed booster rockets, which is the key to making the system reusable. And this is his life’s work.

Jeff Bezos’s Blue Origin launch vehicles are also landing successfully, so the reusability problem is cracked – which will automatically cut launch costs at least tenfold. And other blue-sky space projects are practically tripping over each other as the ideas multiply.

Russian tech billionaire Yuri Milner’s ten-year Breakthrough Listen project is buying thousands of hours of time on the world’s most powerful radio telescopes for researchers seeking signs of civilisations elsewhere in the galaxy. There is “no bigger question in science,” said Prof. Stephen Hawking, who is an adviser to the project.

The 100-Year Starship project, funded partly by NASA, was founded in 2012 to explore the technologies needed to make interstellar space travel a reality a century from now. It is now joined by Icarus Interstellar, whose Project Persephone is working on the design of a ‘generation ship’ that could serve as an interstellar lifeboat for some tiny portion of the human race if the Earth faced disaster in the next century.

Then there is the StarShot project, also backed by Yuri Milner. It’s a five-year, $100 million research programme to design a system of tiny probes consisting of single chips, no bigger than a postage stamp, that would fly to nearby star systems to do close-up observations as they sweep through.

Weighing only one gram, the SpaceChips would be put into orbit, then sent on their way by an array of ground-based lasers focussed on a small light-sail: only a few square metres. The lasers would blast them up to one-fifth of light speed in a few minutes, and then they cruise for twenty years or so until they reach their destination – in the first instance, Proxima Centauri, the nearest star

You couldn’t choose a better target, because astronomers have found an Earth-sized planet circling Proxima that is within that star’s “habitable zone” (where water remains liquid). “We will photograph it close-up,” said Avi Loeb, chair of the advisory committee. “Will it be blue from its oceans, or green from its vegetation, or yellow from its deserts? We will find out.” Get the technology right, and you could do it with thousands of stars.

Like all of these projects, StarShot will require the solution of dozens of difficult technical problems, cost a small fortune, and take years, decades or a lifetime. But it is exhilarating to know that all these projects are underway. At last, the ambitions of the innovators and the explorers begin to match the scale of the task.
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To shorten to 725 words, omit paragraphs 3 and 14. (“I’m less…job”; and “You…stars”)

Panspermia and the Drake Equation: Looking Good

One by one, the empty boxes in the Drake Equation are being filled in with actual numbers, and it’s looking good. So good that Yuri Milner is spending $100 million of his own money over the next ten years to fund the search for non-human civilisations orbiting other stars. But it’s a pity that the Philae lander from the European Space Agency’s Rosetta mission didn’t have more time to look for life on Comet 67P/Churyumov-Gerasimenko.

Yuri Milner is a Silicon Valley billionaire who was working on a PhD in theoretical physics at the Russian Academy of Sciences before he moved to the United States and got rich. His money will buy thousands of hours of radio-telescope time each year to look for radio transmissions from other star systems.

This represents at least a tenfold increase in the amount of work being done on finding intelligent life elsewhere in the galaxy, and Yuri Milner is no fool. Why does he think it’s worth spending this money now?

Probably because the Drake Equation is finally coming into its own. It has seven terms, and American astronomer Frank Drake could not give a value to any of them when he first wrote it in 1961. It was just a formula that would let us estimate the number of civilisations in the Milky Way galaxy when the relevant data eventually became available.

To fill in the first three terms, we needed to know how many stars there are in the galaxy, how many of them have planets, and how many of those planets are in the “habitable zone” where liquid water can exist.

In 1961 the estimate was 100 billion stars. Now it is 400 billion, of which 300 billion are essentially similar to our Sun.

Until 1992, we didn’t even know if other stars had planets circling them. Now we can estimate that at least 40 percent of them do, although the real answer may be almost all of them. (We still cannot detect planets much smaller than Earth.)

As for how many planets are in the “habitable” zone, not too close or too far from their parent star, the answer is probably one or two per star.

Using the data acquired in the past twenty years, NASA now estimates that there are 144 billion habitable planets in our galaxy. Not all of them will harbour life, of course, but that is a very encouraging number.

Other questions remain, however. How many “habitable” planets will actually have life on them? On how many of those planets will an intelligent species appear? How many of those intelligent species will build civilisations that use electromagnetic communications? And how long, on average, would those high-tech civilisations last?

We don’t yet know the answers to any of those questions, but we do know that organic compounds are common even in interstellar space, and that they are continuously raining on our own planet. So the standard assumption is that they somehow combined on Earth to form the first single-celled creatures, and evolution did the rest.

But if it were easy for those organic compounds to combine into complex microbes and viruses, then you would expect it to have happened here a number of times. There would be several or many unrelated genetic lineages on Earth – and there aren’t. All life here has a common ancestor.

So it must be very rare for life to develop spontaneously. If it actually happened here, it would mean that we are a miracle, and pretty much alone in the galaxy. But maybe the miracle happened on another of those 144 billion planets, billions of years ago, and life been spreading through the galaxy ever since – not as alien beings on starships, but as microbes and viruses on meteorites and comets.

This is the “panspermia” hypothesis, first proposed by astronomers Sir Fred Hoyle and Dr Chandra Wickramasinghe in 1974. Dissatisfied with the notion that Earth was unique, they suggested that not only organic compounds but actual microbes and viruses could travel through interstellar space, dormant but still viable in the liquid water that they suspected was present in the interior of many comets.

It sounds weird, but it is just as plausible as the rival hypothesis of an independent origin of life on Earth. Comet 67P/Churyumov-Gerasimenko was the first-ever opportunity to see if this hypothesis holds water (so to speak). The Philae lander did detect sixteen different organic molecules as it bounced along the comet’s surface, but it ended up in the shadows without power to pursue its investigations further.

Pity, but there’ll be another comet along in a while. And if it turns out that Hoyle and Wickramasinghe were right, then most of those 144 billion planets will have life on them. The history of evolution on earth tends always to greater complexity, so a fair proportion of them would have intelligent life on them.

How many of them have high-tech civilisations on them at the moment, of course, depends on how long the average technological civilisation survives. Our own hi-tech civilisation has survived, so far, for about one century.
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To shorten to 725 words, omit paragraphs 5, 6, 7 and 8. (“To fill…star”)