One of the biggest trends in astronomy in the modern era (say since 1950) has been the decreasing reliance on visible light, and the increased reliance on waves that we can’t see, to observe the cosmos. Our ground observatories and now our in-space observatories look more and more at X-rays, radio signals, ultraviolet rays, infrared radiation, microwaves, and high-energy gamma rays in order to figure out “what’s out there”, and what is it doing.
Over the past century, humankind has come a long, long way in what it knows about the cosmos, including how it started and how it’s probably going to wind up A lot of that was made possible by all of the information gathered through these various non-visible observation techniques. Even more will be learned in the near future as our scientists figure out how to detect “gravitational waves“. Those can help us to learn a lot about exotic stuff like black holes and neutron stars and maybe “cosmic strings”. Oh, another cutting-edge technique — observing neutrino particles from space!
Since 2001, the radio astronomers have had an interesting mystery on their hands. They have occasionally recorded very brief but very powerful radio signals coming from beyond the Milky Way. They call these “fast radio bursts“. Since they come from so far, far away, beyond anything that can be observed with regular visible light, the origin of these bursts are not apparent. Different astronomers have different theories on this, but there is no generally accepted answer right now. Whatever is causing them is an extremely powerful energy source; also, given the “fast burst” that we observe, the source might shoot its radio waves in a focused directional beam, and not as a “broadcast” akin to the concentric circles that spread out in a lake after you throw a rock into the water.
There are plenty of things out in the universe that could generate such a focused radio signal. Several researchers favor the notion that these “bursts” are caused by a solar flare from a special type of neutron star, called a “magnetar“. Do “magnetars” have anything to do with magnets? Yes, indeed — magnetars are very dense stars with very strong magnetic fields around them. They are also suspected as being the source of “gamma ray bursts“, another current astrological mystery. Interestingly, gamma rays have the shortest and most energetic wavelengths on the electromagnetic spectrum, whereas radio waves have the longest wavelengths. Those powerful little magnetars out there might really cover a lot of ground!
So, magnetars sound pretty good. But just a few days ago, some Harvard researchers released a pre-publication paper that presents an even more interesting potential source for fast radio bursts. Something more Star Wars like. These scientists say that it is possible — NOT PROBABLE, but at least possible at this point — that the fast radio bursts come from some far-off intelligent civilization. No, not as a way of transmitting tunes and weather reports, they don’t envision an inter-galactic radio station at work here. Instead, they point out that a very high energy radio beam that was precisely focused could be used to propel spaceships across the voids at near-light speed velocity.
The authors admit that this is just speculation. But, it’s not an impossible speculation right now. We humans ourselves are considering using laser beams to push “sailing ships in space” up to very fast speeds to allow them to possibly reach a place like Alpha Centauri, which is a star system about 4.4 light years from earth. The beauty of such a system is that the spaceship does not have to contain a heavy or complex propulsion system of its own, such as the anti-matter engines on Federation Starships like the U.S.S. Enterprise. The Harvard authors speculate that an inter-galactic fast radio burst could push a huge spaceship weighing millions of tons up to near light speed. Perhaps these radio burst are the fingerprint of some technologically advanced civilization sending ‘arks’ of intelligent beings to other star systems so as to colonize distant planets. The paper speculates that the antenna system transmitting these beams would be colossal, possibly taking up an entire planet! Yea, something like the “Death Star”, but much bigger!
Hopefully these huge things would not be battle cruisers going out to make war against a rival civilization — as in a Hollywood sci-fi movie. But don’t worry, even if this were going on, we probably wouldn’t be the target; it would probably involve local stars within the same galaxy. Our Milky Way is very far off from most radio burst sources, separated by huge voids of space. I would like to think that any civilization with this level of technology would have moved beyond the need for war, but . . . if human-kind is any indication, technology has not done such a great job in making seemingly intelligent beings more peaceful.
Again, however, this is all speculation (albeit speculation well beyond the Hollywood level, making it up to the Harvard level). Make no mistake, this paper on fast radio bursts does NOT claim that we finally have proof of intelligent alien life elsewhere in the cosmos. For now, we’re still alone. And there’s probably no way of knowing any time soon if radio bursts really do come from an intelligent source. More likely, a good natural explanation will evolve and be agreed to by most scientists.
Still . . . something like this can’t help but stir the imagination. And imagination is what popular science fiction is all about. So, get ready — Fast Radio Bursts, coming soon to a theater new you!