It is just barely possible that we have discovered the first evidence for some sort of extraterrestrial intelligence. At any rate, astronomers have discovered a star that is something of an anomaly, according to this article.
Three months ago, news broke that a giant “alien megastructure” could exist around a bizarre-looking star 1,500 light-years away.
While the prospect of aliens was first launched by Penn State astronomer Jason Wright, almost everyone in the astronomy community agreed that the chances that this was the case were “very low.“
What makes this star, KIC8462852, so bizarre is the drastic changes in light we see from it over time. Many stars experience temporary fluctuations in brightness, increasing and decreasing in luminosity over time, but KIC8462852’s changes are severe by comparison.
Astronomers refer to stars that experience those fluctuations in luminosity as variable stars. A star can change in brightness either because something occasionally blocks the star’s light, usually a companion star or perhaps a planet, or because the internal processes of the star cause variations in luminosity. Probably every star is at least a little variable. The Sun has its eleven year sunspot cycle, for example. Whether the cause of a star’s variability is external or internal, its cycle of variability tends to be regular. That does not seem to be the case with KIC8462852.
Between 2009 and 2013, astronomers using the Kepler space telescope discovered that it would sometimes lose up to 20% of its brightness. What’s more, the changes didn’t follow any obvious pattern.
That would suggest something gigantic must be blocking the light at random times, meaning that it couldn’t be a planet or other regular orbiting object because that would generate a distinct pattern of dimming light. It must be something that changes shape over time, thereby blocking different levels of light at random intervals.
Could the cause be artificial?
An alien megastructure, called a Dyson swarm, was suggested as one explanation for what scientists have observed, but the most likely reason astronomers came up with was comets — a giant family of them.
But Shaefer says not so fast.
“The comet-family idea was reasonably put forth as the best of the proposals, even while acknowledging that they all were a poor lot,” Schaefer told New Scientist. “But now we have a refutation of the idea, and indeed, of all published ideas.”
To make his discovery, Schaefer had to dig deep down into the astronomy archives at Harvard. It turns out, astronomers have data on KIC8462852 dating back as far as 1890.
By analyzing over 1,200 measurements of this star’s brightness taken from 1890 through 1989, Schaefer found that the irregular dimming of KIC8462852 has been going on for over 100 years. Schaefer published his findings in the online preprint server arXiv.org.
What’s more, he explains in his paper that this “century-long dimming trend requires an estimated 648,000 giant comets (each with 200 km diameter) all orchestrated to pass in front of the star within the last century,” which he said is “completely implausible.”
By killing the comet theory, Schaefer has brought us one step closer to finding out what is really happening around KIC8462852.
At the same time, he’s also reignited the possibility that the source could be an alien megastructure that an advanced alien civilization has been slowly building over time. One thing’s certain for Schaefer: The bizarre dimmings are probably caused by a single, physical mechanism that’s undergoing some type of ongoing change.
“The century-long dimming and the day-long dips are both just extreme ends of a spectrum of timescales for unique dimming events, so by Ockham’s Razor, all this is produced by one physical mechanism,” Shaefer said in his paper. “This one mechanism does not appear as any isolated catastrophic event in the last century, but rather must be some ongoing process with continuous effects.”
Schaefer isn’t the only one interested in learning more about KIC8462852. Late last year, astronomer Doug Vakoch and his team at the new organization called SETI (Search for Extraterrestrial Intelligence) International — not to be confused with the SETI Institute — went hunting for aliens around KIC8462852.
They searched for signals that an alien civilization might be beaming toward Earth either in radio or visible wavelengths, but ultimately they came up empty handed. So, if it is aliens, then they’re being awfully quiet.
Is it aliens? If this is some structure created by an extraterrestrial civilization, we shouldn’t expect to be receiving any sort of messages from them. They would have no reason to believe that there is any intelligent life here on Earth since any radio waves we have emitted cannot be farther than about 100 light years away by now. Any message to or from KIC8462582 would take 1500 years to reach its destination. They may have sent a message last year but we won’t get it for a long time.
I tend to think, however, that the explanation for the strange behavior of KIC8462582 will turn out to be due to an entirely natural phenomenon.I think that as we begin to explore the universe we will find that life is fairly common. The elements and compounds that make up the basic components of life are found throughout the universe and if the current understanding of the earliest history of the Earth is accurate, it seems that life arose on this planet as soon as it was physically possible. Scientists do not know precisely how life began on Earth, but I think that they will find that where ever the right conditions are found, there will be life of some sort. I think, though, that most of the life we find in the universe is going to be simple and primitive, some equivalent of terrestrial bacteria. Bacteria were the only form of life found on Earth for most of its history. Intelligent life must be still rarer. Human beings have only been around much less than 1% of the Earth’s history and we have only had to capability to communicate by radio for a little over a century. There doesn’t seem to be any reason to believe that the development of intelligent life or a technological civilization was inevitable and considering the strange twists and turns of the history of life it may not be very probable. I think then, that we will find some few worlds with alien plants or animals, but that we are probably the only intelligent form of life in our galaxy.
Even if there are extraterrestrial civilizations, our relations with them will not be like Star Wars or Star Trek in which there are a number of different races at about the same level of technology. It is more likely that if two civilizations make contact, one civilization will be millions of years ahead of the other. Any space wars are likely to be short and decisive with the more advanced civilization quickly overcoming the more primitive. With that in mind, maybe we shouldn’t be trying to draw attention to ourselves. I would hate to think that there is a fleet of conquistadors from KIC8462852 heading this way.
- The Most Overhyped Scientific Discoveries of 2015 (gizmodo.com)
- Do We Live In A Star Wars Universe? (blogs.scientificamerican.com) Probably not.
- First Contact With Extraterrestials Would Have Minimal Impact on the Day-to-day Life of Puny Humans (secretsofthefed.com) That would depend on the nature of the first contact.
- Mysterious dimming star: probably comet fragments not an alien… (sci-universe.com)