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An artist's conception of how the under-construction Shanghai Tower will look next to the Jin Mao Tower and the Shanghai World Financial Center
I have written a post about non-human builders, unknown builders, and ambitious (but not-entirely-successful) builders. What about the great builders of the present? Sadly the west is moribund right now, suffering not just from the housing-bust hangover but from crooked financiers, incompetent politicians, social stalemate, and a dearth of ideas. This situation is probably not permanent but it makes me disinclined to write about the shabby projects going up right now. I suppose I could write about the monstrous white elephant skyscrapers of Dubai, that autocratic dystopia in a desert, or describe the towers of Singapore, the hard-headed, hard-hearted city state. But not only do I not admire those societies, they are a side show on the world stage (and a tiny sideshow at that). Right now all eyes are on China. The Middle Kingdom is sucking up the world’s energy resources and every sort of raw material at exponential rates. In return, cities are going up where no cities existed before. China is rolling out roads, airports, and railroads at a rate never before seen. An agricultural nation is turning into an urban one. And China’s greatest cities are becoming the great cities of earth, morphing overnight into forests of mega skyscrapers.
But that is not the subject of this post either. The real question about China’s rise is whether the nation will be able to harness its wealth to become a titan in scientific and technological fields the same way it is dominating manufacturing. Part of the answer to that question can be found in Guizhou province in southern China where a massive bowl shape is rising from the hills. This is the initial superstructure for the five-hundred-meter (546-yard) Aperture Spherical radio Telescope (FAST) which is due to open in 2016. FAST will then supplant the Arecibo radio telescope in Puerto Rico (which was built in 1963) as the largest single-aperture telescope ever constructed. To quote ElectronicsWeekly.com:
When completed, its 500-metre diameter single dish will make it the largest and most sensitive radio telescope in the world. What’s more, although FAST’s dish will be fixed in its crater-like setting, a series of large motors will be able to change the shape of its reflective surface, allowing it to scan large swathes of the sky. FAST will be able to peer three times further into the universe than Arecibo. Astronomers expect it to uncover thousands of new galaxies and deep-sky objects up to 7 billion light years away.
FAST will be the planet’s eye into deep space (and just, in time: Arecibo’s budget is on the chopping block as congress pares away scientific funding). The remote location is unusually free of radio interference and the natural bowl-shaped valley it is located in should help amplify its utility. According to National Astronomical Observatories at the Chinese Academy of Sciences, the telescope will be available to international astronomy researchers.
Since the moon is the closest celestial body to earth and the most easily observed with a telescope, it was a natural place for Herschel to begin his search for extraterrestrials. In a letter to a friend, Herschel described how he believed the craters of the moon were Lunarian cities and dwellings (laid out like the Roman “circus” meaning a large ring):
As upon the Earth several Alterations have been, and are daily, made of a size sufficient to be seen by the inhabitants of the Moon, such as building Towns, cutting canals for Navigation, making turnpike roads &c: may we not expect something of a similar Nature on the Moon? – There is a reason to be assigned for circular-Buildings on the Moon, which is that, as the Atmosphere there is much rarer than ours and of consequence not so capable of refracting and (by means of clouds shining therein) reflecting the light of the sun, it is natural enough to suppose that a Circus will remedy this deficiency, For in that shape of Building one half will have the directed light and the other half the reflected light of the Sun. Perhaps, then on the Moon every town is one very large Circus?…Should this be true ought we not to watch the erection of any new small Circus as the Lunarians may the Building of a new Town on the Earth….By reflecting a little on the subject I am almost convinced that those numberless small Circuses we see on the Moon are the works of the Lunarians and may be called their Towns….Now if we could discover any new erection it is evident an exact list of those Towns that are already built will be necessary. But this is no easy undertaking to make out, and will require the observation of many a careful Astronomer and the most capital Instruments that can be had. However this is what I will begin.
Of course this spectacular misapprehension becomes more comprehensible considering how long it took humanity to understand the nature of craters (it wasn’t until the 1960’s that work by astrogeologist Gene Shoemaker, brought about widespread scientific consensus that craters were caused by impacts). Yet Herschel was so devoted to his Lunarians that he came perilously close to inventing findings. As he carefully scrutinized the moon for other living things night after night, imperfect optics and his yearning for alien life sometimes got the best of him. Here is a drawing of a shadow which he perceived might be a forest.
Herschel did not believe that the moon was the only other sphere to support life–he believed that life could be found on all heavenly bodies which are spherical from self-gravitation. And Herschel really meant all such bodies: in the Royal Society’s Philosophical Transactions in 1795 he speculated about beings living on the sun,
The sun…appears to be nothing else than a very eminent, large, and lucid planet, evidently the first, or in strictness of speaking, the only primary one of our system….Its similarity to the other globes of the solar system …leads us to suppose that it is most probably inhabited …by beings whose organs are adapted to the peculiar circumstances of that vast globe.
Hershel thought that all of the stars in the universe were like the sun—densely habited and supporting an orbiting network of habited worlds. He wrote “since stars appear to be suns, and suns, according to the common opinion, are bodies that serve to enlighten, warm, and sustain a system of planets, we may have an idea of numberless globes that serve for the habitation of living creatures.” Additionally, Herschel believed that the nebula he observed were other “universes” like our own, each containing innumerable stars—all of which were habited. He was wrong in his interpretation of the particular gaseous nebulae he was looking at, but he was quite right about the existence and nature of other galaxies (although this idea was not proved or accepted until the work of Edwin Hubble).
Poor Herschel’s hunches about extraterrestrial life seem quaint to us now. Couched in boyish exuberance and 18th century idioms, they almost seem risible. Yet Herschel was right about exoplanets and about galaxies beyond our own. He seems to have been the only person of his time to begin to apprehend how vast the universe really is. Thanks to the work of many scientists and explorers we can write off life on the moon and (almost certainly) the sun. However, even with our robot probes and our telescopes, the solar system is shockingly unknown. And beyond the solar system, the large exoplanets we currently know about are strange hot giants we did not expect. The preliminary results of the Kepler mission are beginning to trickle in, and they hint at a profusion of planets (and other things) much more heterogeneous and odd than cosmic uniformitarians might expect. If blogging has taught me one thing, it is not to underestimate Sir Frederick William Herschel (a conclusion I hardly anticipated). So while I chuckle about the perfectly circular cities of the lunarians, I am also keeping an open mind about the immense number of unknown worlds.
Also (as I suspect Sir William felt), I am sad about how many things are simply unknowable.