A Recent spectrographic study of data from the Sloan Digital Sky Survey by two scientists from the University of Laval in Quebec, Canada, E.F. Borra and E. Trottier, has produced some shocking results. It revealed that 234 star systems quite similar to our own sun were producing unique light pulses that could be extraterrestrial communications. Possible laser signals from an alien civilization. The scientist’s research has been published under the title Discovery of peculiar periodic spectral modulations in a small fraction of solar-type stars in the academic journal Publications of the Astronomical Society of the Pacific.
Widely reported as a sensational breakthrough in the search for extraterrestrial life. It is possibly the strongest indication of a structured signal from another star system ever found. There is much more research to be done, and results are only preliminary. It is a purely scientific paper and very hard to read unless you’re an astronomer. Covered by many mainstream media in typical glancing fashion this article will take a deeper look.
What is much more readable is the original paper by one of the scientists predicting what an alien signal may look like. Written by Ermanno F. Borra in the Astronomical Journal entitled SEARCHING FOR EXTRATERRESTRIAL INTELLIGENCE SIGNALS IN ASTRONOMICAL SPECTRA, INCLUDING EXISTING DATA. The paper is the reason the pulses were detected at all. It is highly recommended any casual fan of science read it. Describing what an alien pulsed laser signal may look like, the infrastructure needed and capabilities of mankind to produce these signals with current technology. In doing so, it answers many questions and creates much more.
Without going into the technical terms of the paper, which you can do for yourself, some major points will be examined. An alien world wanting to communicate over a vast distant would realize other intelligent species may be cataloging the stars as well. Therefore the civilization wishing to communicate ( possibly us ) would need a sufficiently powerful laser. This laser would need to be pulsed in such a way by nanoseconds. Sometimes a constant interval between pulses. Sometimes a changing interval between the pulses. Made to look like nothing else in the sky, a mildly advanced civilization would not mistake it in a routine sky survey. This is what was observed in the Sloan Digital Sky Survey data from 234 suns like stars.
Clearly, such a signal in an astronomical source is strange. If detected in a spectrum, the object would obviously be observed again. The ETI obviously also knows this. They may thus make it look even more peculiar by inducing unnatural time variations generated by changing the time between pulses (τ in Equations (1) and (2)) in an artificial sequence. There would then be little doubt that it is an ETI signal.
The paper goes on to describe how powerful of a laser would be needed to send a pulse communication over a reasonable distant. It also describes a vast infrastructure an alien civilization might build to scale up these signals. Laser technology would need to be fairly advanced to do this. An example in the paper uses the metric of 1000 light years and clearly, explains we have the current resources do it right now. Such a system could reach one million sun-like stars with pulsed light communications. This was proposed in 2004.
For this, we shall use the analysis in Howard et al. (2004), who considered the energy requirements for an ETI trying to communicate with nanosecond optical pulses. They considered the feasibility of interstellar communications with technology available at the time the paper was written. They assumed communications within a 1000 lt-yr diameter region surrounding Earth that would contain about 1 million Sun-like stars. They assumed that a diode-pumped laser similar to the Helios laser designed at Lawrence Livermore National Laboratory for inertial confinement fusion would be used
The example uses the Helios laser designed at Lawrence Livermore National Laboratory for fusion experiments and nuclear stockpile maintenance. Interesting as there is very little mention of this laser to be found. Except on page 182 of Laser: Light of a Million Uses and an old press release from the New Scientist describing it as 10-kilo- joule Helios carbon dioxide laser. Most probably because of its use in nuclear stockpile maintenance and fusion experiments! It is odd however that it is mentioned as a means of interstellar communication with hardly anything to find on the subject.
It is also interesting to note that for decades The Lawrence Livermore National Laboratory has been studying laser communications and light propulsion. Using electromagnetic beams as a means for high thrust to weight capability and mid-flight satellite readjustment. High-intensity lasers would be used to propel craft by igniting a solid concave fuel plate with no need for heavy engines. Another technique is simply bouncing electromagnetic waves it off special reflectors to make adjustments of assets already in space eliminating on board propulsion systems. Electromagnetic propulsion is being proposed as a means to power tiny interstellar probes that could go much faster than conventional unmanned spacecraft.
Consider that lasers are much more powerful than they were in 2004. Advanced satellite communications and even the International Space Station use laser pulses to transmit and receive in high definition. Imagine we have had the technology locked up in secret programs that can admittedly communicate 1000 light years across the universe to possibly one million sun-like stars since the late 90s. This does not mean you could Facebook or instant message E.T. because it would take up to 2000 years, depending on the distant, to get a response. It would only be a means of just saying that we are here. As alien civilizations may be doing already and we have the ability to do now.
Stephen Hawking recently said that if we find alien signals don’t send any back and just listen for now. He must be keenly aware of this type of technology as the scientific papers referenced here were widely circulated. Hawking himself has advanced the idea of tiny space probes powered by electromagnetic beams to explore the galaxy. These could go fast enough to travel interstellar space. The warning stands true but most don’t realize that we can answer back.
Reading past the headlines of little green men (even if they exist) and gee whiz articles. What is the state of current technology? How far has this technology come and are we sending or own message in a bottle? It is clearly possible.
RaptormanReports
Sources:
https://arxiv.org/abs/1610.03031
http://iopscience.iop.org/article/10.1088/0004-6256/144/6/181
Alien Contact. Can We Answer Back?
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