This is a great 10-part overview of Boyajian’s Star (Tabby’s Star/KIC 8462852) by astronomer and astrophysicist Jason Wright, outlining the various hypotheses to date to explain this weird star observed by the Kepler Space Telescope. Whatever is causing the unusual short-term and long-term dimming is still unknown.
It may sound cliche, but the question ‘Are we alone?’ is still one that captures the imagination of many people, including of course, scientists. With the now regular discovery of exoplanets orbiting other stars, the prospect that there may be other intelligent life out there somewhere (or any kind of life) has only become more exciting and compelling. When it comes to intelligent extraterrestrials, SETI is a name that has become part of our modern culture, the Search for Extra-Terrestrial Intelligence. SETI focuses on looking for radio and optical signals that could originate from an advanced society, a technique that in itself has generated much debate. After several decades of searching, a definitive signal has yet to be found, but there have been tantalizing possibilities. Unfortunately, none of those have yet panned out as the signal. Now, another interesting radio signal is making the news – could it be the evidence scientists are looking for or is it another dead-end?
As has been reported previously, there is something weird going on around a star which is a little over 1,400 light-years away. Astronomers are still baffled as to just what that is, and theories have ranged from a huge mass of comets to alien megastructures. Indeed, comets had become the leading explanation offered for the star’s odd behaviour, although that was really just the best of a bunch of ideas which all had flaws in them. Now, new research shows that the comet explanation is even less likely to be the answer, although the actual explanation is still as elusive as ever. Needless to say, this has resulted in a lot of discussion and debate in the past few months.
There has been a lot of discussion during the past several days regarding a discovery by the Kepler Space Telescope, which, according to some, may be the first evidence for advanced extraterrestrial intelligence, or perhaps just a weird but natural phenomenon instead.
We still don’t know if there is life elsewhere in the universe, but scientists are working on techniques to better understand how it may have originated anyway, in the event that such alien biology is indeed discovered, even if just simple microbes. Focusing on exoplanets, the research suggests that if multiple inhabited worlds were found, then researchers could look for patterns similar to those found in epidemics on Earth, which might provide evidence for panspermia, the theory that life could spread through our galaxy from one habitable planet to another.
Researchers at Cornell University are taking a new approach to the search for alien life: looking for habitable planets older than Earth, “old Earth analogues,” which may be nearing the end of their habitable lifetimes. Astronomers would search for biosignatures from worlds much older than Earth, where lifeforms are dying off due to circumstances such as the planet’s star expanding in its old age, gradually heating the planet to a point where life is no longer possible.
Since the SETI program first began searching for possible alien radio signals a few decades ago, there have been many false alarms but also instances of fleeting signals of interest which disappeared again as quickly as they had appeared. If a potential signal doesn’t repeat itself so it can be more carefully observed, then it is virtually impossible to determine whether it is of truly cosmic origin. One such signal in particular caught astronomers’ interest on August 15, 1977. The famous “Wow!” signal was detected by the Big Ear Radio Observatory at Ohio State University; it was thirty times stronger than the background noise but lasted only 72 seconds and was never heard again despite repeated subsequent searches.
In a new book titled The Elusive Wow, amateur astronomer Robert Gray chronicles the quest for the answer to this enduring puzzle…
See Universe Today for the full article.
In the famous words of Arthur C. Clarke, “Any sufficiently advanced technology is indistinguishable from magic.” This phrase is often quoted to express the idea that an alien civilization which may be thousands or millions of years older than us would have technology so far ahead of ours that to us it would appear to be “magic.”
Now, a variation of that thought has come from Canadian science fiction writer Karl Schroeder, who posits that ”any sufficiently advanced technology is indistinguishable from nature.” The reasoning is that if a civilization manages to exist that long, it would inevitably “go green” to such an extent that it would no longer leave any detectable waste products behind. Its artificial signatures would blend in with those of the natural universe, making it much more difficult to detect them by simply searching for artificial constructs versus natural ones…
See Universe Today for the full article.
As the Kepler space telescope begins finding its first Earth-sized exoplanets, with the ultimate goal of finding ones that are actually Earth-like, it would seem natural that the SETI (Search for Extraterrestrial Intelligence) program would take a look at them as well, in the continuing search for alien radio signals. That is exactly what SETI scientists are doing, and they’ve started releasing some of their preliminary results…
See Universe Today for the full article.
In the search for extraterrestrial life, the focus has long been in two primary areas – looking for evidence of microscopic organisms, either past or present, or radio/optical signals from other civilizations. What about other options? What about physical artifacts from advanced space-faring societies? While this may seem like a real long-shot or even unbelievable to many, it is considered to be a possibility by some scientists according to this news article from Penn State University. Perhaps unmanned probes, much like the ones we ourselves have already sent out to a growing number of planets and moons, and even outside of our solar system altogether. But could we find them if they existed?
So far, no obvious evidence for anything like this has been found, although there are oddities such as the “monolith” on Mars’ moon Phobos, an unusual-looking tall bump or protuberance on the surface seen by the Mars Global Surveyor orbiter, but not in enough detail yet to see what it actually is. Many other oddities have been reported on the Moon, Mars and other moons in the solar system over the years. Of course, many are illusions or examples of pareidolia, while others may be worthy of closer study. That is an entire subject in itself.
According to Jacob Haqq-Misra, of the Rock Ethics Institute, and Ravi Kumar Kopparapu, of the Earth and Environmental Systems Institute, “The vastness of space, combined with our limited searches to date, implies that any remote unpiloted exploratory probes of extraterrestrial origin would likely remain unnoticed.” They are publishing a paper which has been accepted by Acta Astronautica and posted online on ArXiv. They continued however, “Extraterrestrial artifacts may exist in the solar system without our knowledge simply because we have not yet searched sufficiently. Few if any of the attempts would be capable of detecting a 1 to 10 meter (3 to 33 foot) probe.”
They have devised a probabilistic method to try to determine how likely it may be to find such artifacts in our solar system. Their conclusion? It would be difficult at this point to say that there aren’t any. That may seem simplistic, but as they noted, there are many places in the solar system which just haven’t been explored enough yet. “The surface of the Earth is one of the few places in the solar system that has been almost completely examined at a spatial resolution of less than 3 feet,” they said.
They summed it up this way: “Searches to date of the solar system are sufficiently incomplete that we cannot rule out the possibility that nonterrestrial artifacts are present and may even be observing us. The completeness of our search for nonterrestrial objects will inevitably increase as we continue to explore the moon, Mars and other nearby regions of space.”
Such a discovery would be momentous if it happened, but for now we can only speculate and keep our eyes open as we continue exploring.