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The extraterrestrial spies
Now that humans have sent probes successfully to another planet to discover its secrets, could any extraterrestrial civilization have done the same thing? Sent intelligent, sophisticated probes to spy on Earth?
It is the most interesting thought that light years away from the Earth, someone could be watching us, monitoring our evolutionary progress and sending back the data to an unknown far off planet.
Sounds like a sci-fic episode, doesn’t it? But some of the expert scientists seem to think it might be possible. Allen Tough of the University of Toronto is of the opinion that a serious search for these possible “Alien Bugs” should be undertaken. One might ask to what purpose would this alien spying make any sense. What would it achieve? After all there has to be a reason for this snooping around.
There are many hundred billion star systems in our galaxy and the idea of sending probes across such vast distances in space would be a tough thing to get approved by some alien “high command.” A distance of a 100,000 light years in diametre is hardly “in the nieghbourhood.”
Though a far-fetched scenario, this idea can’t be outrightly termed as impossibile, think scientists. Dr Seth Shostak of the SETI Institute says, “advanced societies, even those that are modestly beyond our own, will have catalogues of planets known to support life. This inventory can be assembled by using large telescopes to collect and analyze the light reflected from the atmospheres of other worlds; looking for ‘biomarkers,’ such as oxygen and methane.”
If these valuable clues are detected on another planet, they would prove the presence of biology. It is a surprising fact that even microbes can be detected by this method over vast distances of light years. If life is a common occurrence in the galaxy, then maybe one that is detected close enough to an advanced alien civilization will merit sending in a probe.
Also, it is not necessary to have a large number of probes, believes Allen Tough. He writes that these bugs “could be smarter than any human being, yet…be smaller than a basketball or baseball.”
The reason for the small size would be that less energy would be required to send them hurtling to distant worlds and they would be much harder to find and destroy by inhospitable beings.
But there is an important aspect here. If the probes are too tiny and do not possess the required power to send back important data, they would be useless. This could be done by radio signal or by infrared laser. Dr. Shostak feels, “the aliens might opt for a ‘master-slave’ set-up somewhat akin to the scheme used to retrieve data from the Mars rovers.”
Near the orbit of Earth, a small probe could go round collection valuable information and high resolution images and “beam” it back to a “mothership” positioned somewhere in the asteroid belt. This “mothership” would receive the data and relay it back to the home planet. However, there is also another possibility. There could be just one probe orbiting at a further distance…probably on a short-period comet. Which would keep it out of sight and come close occasionally. Maybe every few decades. How expensive would such an adventure be for the aliens? Not very exorbitant, feel the experts.
According to Dr. Shostak, “If the probe weighs ten pounds, the minimum energy necessary to rocket it to target and then slow it down on arrival is roughly 5,000 trillion joules. If you buy that much energy from your local electric company, it will cost you $120 million.” Though a reasonably high cost, it is not unachievable if the aliens are really interested and rich.
And why might one ask, would they be so interested. After all, they can easily catch our television broadcasts and find out what’s happening. But, finding a planet with evolving biology for 500 million years, leading to intelligent life, might warrant a closer look. We are, not to sound too pompous, a truly beautifully landscaped world filled with innumerable species of animal and plant life. A giant “natural history” museum full of wonderful and complex creatures. Thus, one can safely assume that the “alien bugs” and probes are a strong possibility.
“Maybe one was launched our way, sometime in the last two billion years,” assumes Dr Shostak. He further states, “we might still be able to find it if we knew where to look. Should we make a careful investigation of the asteroid belt? The Earth-Moon Langrage points? Perhaps parked in a nearby orbit, or on Earth itself?”
Can it be done?
The problem is that scientists do not know where to begin to look. The search would be a most daunting one. When the first extrasolar were found around other stars, former Nasa administrator, Daniel Goldin, on a PBS television show, in 1997, enthusiastically exclaimed, “Could you imagine if in twenty-five or thirty, or forty years, we could take the picture of a planet that’s perhaps fifty light years away from Earth, and…if the resolution was high enough…to take a picture of oceans and clouds and continents and mountain ranges, breathtaking!”
If an alien civilization is advanced enough, it too would be most interested and intrigued. So what would a civilization 50 light years require to map another world? And if the aliens really do have accurate information regarding the movements and distances of stars, something that our astronomers on Earth will probably have in a century, they will be able to send broadcasts to just the inner solar systems of likely candidate stars.
According to Dr Shostak, what would a civilization 50 light years away require to map another world? “with a bit of high school physics, you can work out that this necessitates a telescope with a mirror two thousand miles across. It wouldn’t have to be a one-piece mirror of course: you could borrow a technique in vogue with contemporary astronomers, and construct your instrument out of smaller, widely separated, individual telescopes.”
The extremely large “spy-glass” would have to be space-based so that there could be no atmospheric blurring and if a civilization is capable of building such a telescope, it would also have the know-how and power required to lift it off into space.
Could the aliens have known about the dinosaurs just by taking an image of them from far away? Is it possible for a civilization, which is capable of huge engineering projects to build instruments that could “see” life on Earth?
Making an image of a T-Rex or even a human being would require foot size pixels, according to scientific estimates. At a distance of 50 light years, this would require a 500 million-mile telescope. Something that, if built by human beings, would fit between the Sun and Jupiter!
A massive instrument by any standard. But, assumes, Dr. Shostak, “what’s to stop an alien civilization from scattering small telescopes throughout its solar system, thereby achieving this impressive aperture size?” Not much, really. That is if they are many millennia advanced than us.
So, are we being watched, scrutinized and assessed by some alien civilization while we watch another planet?
While we try to put another alien world under a microscope, are we being closely observed? We don’t really know and won’t till we catch and alien “bug.”
The writer
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