Last week I wrote about the WOW! Signal. The most likely candidate for a formal effort of contact from extra-terrestrials due to its irregular and almost artificial qualities. This does pose a thought, are radio waves the best way to establish contact?
Although radio signals are received by radio telescopes every day, some are extremely difficult to decipher or can be interpreted as having a natural origin. So many cosmological objects can cause bursts of radio waves from the electromagnetic spectrum, black holes, quasars, supernovae and rapidly rotating neutron stars to name a few.
We have been receiving radio signals for decades. Is it possible that we are attributing some artificial signals as natural phenomena? Given radio pulses and signals are sent in almost every direction in the cosmos, we haven’t received a formal decipherable reply. It would seem that we should go back to the drawing board surely?
There are other ways and means to make a large artificial signal that could grab our attention or otherwise the attention of others should they be out there? One idea would be a giant cosmic billboard! Yes, I know this sounds absurd but hear this one out. We can discover other planets orbiting stars because of a dip in starlight we observe when the planet passes in front of the parent star. That is the planet coming between our telescope lens and the star that it orbits. The hubble can observe a circular dot moving uniformly across the star.
So how about a clearly man/extra-terrestrial made object passing in front of a star? If we launch a large object into our solar system to orbit the Sun or Earth in the shape of a triangle that clearly isn’t a natural object. If we observed a triangular object orbiting a star deep into the cosmos that we didn’t put there, that would be the proof of extra-terrestrial life.
Although this idea is our own, we cannot count on aliens having the same trains of thought, should they be out there of course! Our planet has two objects outside the heliosphere of our solar system, Voyager 1 and 2 launched in the mid 1970’s. In time, the New Horizons probe that discovered Pluto will one day leave our solar system as well. So this begs the question, if there are other planets with space programmes where are they and where is all their stuff? Probes, telescopes and all the other gadgets we have launched over the years.
Radio waves are not the most efficient way to try and establish contact. Although the speed of light is the fastest thing we can observe, in cosmic terms it is agonisingly slow. The speed of light and its implications is by far my favourite astrophysical topic and this point deserves an entire post on its own next week.