The universe is a strange place by its very nature.
Mysterious questions abound over dark matter, dark energy, how it all came to be and so
on.
But at the same time, as our astronomical instrumentation has improved, in modern times
we have been able to study the universe in unprecedented detail.
As that process has unfolded, the universe has rewarded us with both understanding, but
also new mysteries, many of which have not been solved.
In the course of making this channel, I’ve run across and covered many such astronomical
mysteries, some of them now solved, some of them not.
But there has always been a core group that offer possibilities so weird, that they continue
to baffle scientists to this day.
So here are 10 Unsettling Astronomical Incidents and Phenomena.
Number 10 The Nature of Pulsars
When pulsars were first discovered in the 1960’s the possibility that they were alien
beacons had to be seriously considered after it was shown that they were not a product
of earth interference.
They were, after all, highly unnatural looking pulses of electromagnetic radiation that repeated
with such regularity that some of them rivaled the accuracy of atomic clocks.
In the years since, we’ve learned that they are just an unusual case of nature emitting
a regular signal by way of a rapidly rotating neutron star.
This would seemingly lay the idea of alien involvement with pulsars to rest.
Except, it actually doesn’t.
In 2017, Clement Vidal authored a paper that reopened the question of an alien technological
origin for pulars, or at least a certain class of them that could have been natural objects
tweaked by aliens for communications.
He pointed out that there were five reasons that aliens were originally taken off the
table as an explanation.
The first was the truly titanic amounts of energy involved, it seemed unlikely to some
that a civilization would use that kind of energy.
Trouble is, we’ve never seen an alien civilization and really have no idea what they would be
capable of energy wise, and we do still talk about galaxy spanning Kardashev type III civilizations
that would command far more energy than a pulsar.
The other four reasons are equally problematic.
One was that they are not unique.
In other words, how likely would it be that two seperate civilizations would broadcast
the same way at similar frequencies.
Well, our earth civilizations do that, and SETI does spend a lot of time looking for
aliens at the frequency 1420 Mhz because there are inherent scientific advantages to do so
that alien scientists would also know about.
Perhaps that could be the case with pulsars.
Another reason was that pulsars generally do not emanate from planetary systems, but
who says aliens have to stick to a planet?
Also, they are not narrowband, kicking out broadband transmissions wastes energy and
technology generally sticks to narrowband as a result.
But if pulsars started out as natural objects, that are being tweaked for communications
by exocivilizations, then broadband may just be a natural leftover artifact.
But the fifth argument is the most solid.
We have perfectly good natural explanations for pulsars that fit the bill.
There really isn’t a reason or need to evoke aliens when something appears explained and
natural.
But that doesn’t eliminate the pesky possibility that pulsars could be tweaked by an exocivilization
as a natural carrier for communications and that, maybe, we should look for that, especially
in light that some of them are extremely accurate in their pulses, to the point that they could
be used for something like a navigational beacon.
That near absolute regularity present in some pulsars does still look a bit odd, decades
after they were first detected.
Number 9 Fast Radio Bursts
This particular phenomenon is a relatively new one, having only been discovered in 2007.
They come as a very quick bursts of radio waves that arrive in such a way that scientists
know that while extremely powerful, they must come from very small sources that are very
likely outside our galaxy, limiting what could be causing them.
Further limiting what they might be is that at least one has been seen to repeat, seemingly
ruling out any sort of cataclysmic event, such as a black hole merger.
Most hypotheses currently on the table involve neutron stars or magnetars in some sort of
odd situation, but it’s also hypothetically possible that they could be of alien origin.
In 2017, Manasvi Lingham and Abraham Loeb released a paper, link below, explaining that
it’s possible that the origin of at least some of them could be leakage from alien light
sails, because the frequencies at which FRBs are detected happen to also be optimum frequencies
for use with light sails.
More, given that the FRBs have been shown to originate from very small sources, they
point out that the emitter for a light sail would need to be about twice the diameter
of Earth, well within the constraints on what could be producing FRBs.
Number 8 The Dyson Sphere Candidates
Sometimes ideas within the realm of futurism can be so speculative that, if realized, are
probably going to prove impractical.
One such concept is the Dyson Sphere, though it should more accurately be called a Stapledon
Sphere, after the sci fi author that envisioned them in the 1930’s, as opposed to Dyson’s
actual vision of a swarm of energy collectors.
To actually encase a star within a solid shell would be a megastructure undertaking of truly
titanic proportions that would involve things like completely disassembling planets for
raw materials.
And, it’s not entirely clear how such a thing would be engineered, constructed and
maintained.
Surprisingly however, out of all the hypothetical alien megastructures that we have yet envisioned,
the Dyson Sphere remains the only one for which we have detected candidates, though
they probably aren’t very good ones and are likely really due to natural phenomena.
The detections stem from a search of infrared data from the IRAS satellite done by scientists
at FermiLab.
The idea is that Dyson Spheres absorbing energy from their star would re-emit that energy
in the infrared in a specific, detectable way.
They found 17 candidates that fit, though they were very ambiguous and probably have
natural explanations, though efforts to figure out what they are are ongoing, and another
project to search for them using the GAIA spacecraft has already yielded a further two
eyebrow raisers, TYC 7169-1532-1 and TYC 6111-1162-1 though again they are really ambiguous.
Nothing definitive, but in coming years if civilizations do indeed encase their stars
in Dyson Spheres, it seems likely we’ll spot it.
Number 7 The Phantom Planet
Unlike most of the phenomena on this list, this one could well be explained within the
next few years, as several groups of scientists are actively looking for it.
The motion of objects in the outer solar system is peculiar, as though they were disturbed
by a large object in the outer solar system.
In fact, yet another object showing orbital peculiarities consistent with this was found
recently, bolstering the case that another planet exists in this solar system much further
out than the orbit of Neptune.
One possibility is that it’s the solar system’s missing super earth.
Our star system is unusual because we lack a super earth, seemingly one of the more common
types of planets in the Milky Way.
This hypothetical planet may have formed closer into the solar system, but might have been
pushed out early in the solar system’s history.
Another possibility is that it may not be from this solar system at all, and may be
a captured object the sun acquired at some point in its history, in which case it would
truly be an alien interloper in our star system, and would offer a chance at studying an actual
former exoplanet that formed somewhere else.
While it’s not universally accepted that Planet 9 must be out there, there is also
an arguement that the data is skewed and it may not exist at all, whatever the case, as
hints of this phantom planet’s existence continue to surface, it seems very possible
that within a few years we may well have another known planet to explore.
Number 6 TYC 8241 2652
This entry is truly bizarre because not only is there no ready explanation for it having
happened, but also no ready explanation for how fast it happened.
In 1983 the star TYC 8241 2652 was observed in the infra-red to have a debris disk.
That in itself is nothing unusual, dust disks are a normal part of planetary formation,
and indeed earth itself formed from one.
And over time, a very long time in geologic terms, these disks tend to clear out as stable
planetary systems develop.
When TYC 8241 2652 was observed in 2010, the dust disk had completely disappeared, not
in millions of years, but in the time since a previous observation in 2008.
Whatever caused the dust’s disappearance did it under two years.
Numerous natural explanations were suggested for just how that could happen, only to fall
flat and the cause for the disappearance remains a mystery, and has been seen in no other star
system with debris disks since.
Number 5 234 Detections of Something Strange
Occasionally, a scientific paper will come out that’s seemingly worthy of attention
and then instantly go into obscurity.
That’s essentially what happened with a paper by Ermanno Borra and E. Trottier in
2016.
It related to an earlier paper by Borra where he predicted that certain types of pulses
could be produced by current technology and be detected a thousand light years away, and
vice versa.
Borra then searched existing data for anything that might look like those kinds of signals.
He found 234 of them.
Now, the media at the time sensationalized the story and in some cases badly reported
it as though aliens had been found.
This was not the case, and the scientists themselves made no claims that this was an
actual detection of alien civilizations, merely that that was a possibility and that further
follow-up work should be done.
And that’s where it sits today, but one thing still stands out.
Nearly all of the detections where coming from stars of spectral types believed to be
suitable for life.
1220-91-1 Number 4 The Wow!
Signal
This bizarre signal in some ways gets even more bizarre as time goes on simply because
an alien origin for it cannot be ruled out, even though the signal was detected over four
decades ago.
In 1977 (check) astronomer Jerry Ehman using the Big Ear radio telescope at the Ohio State
University picked up a signal.
This signal was noteworthy for several reasons.
The first is that it was very close to 1420 Megahertz, which is the frequency at which
hydrogen, the most common element in the universe, emits radio waves.
This frequency is of note to SETI scientists, in fact it’s set aside and not broadcasted
on specifically for this reason, because any alien civilization that possesses science
and radio transmitters would know of this frequency.
As a result, it might be a universal frequency to broadcast a contact signal.
The second is that the Wow!
Signal was strong.
Very strong, which is why Dr. Ehman famously wrote wow on the printout.
The third strange thing about this signal is that it was narrowband, which is in itself
very odd.
Nature tends to emit radio signals broadband, whereas technology tends towards narrowband.
Another odd aspect of Wow is the fact that it was a very brief signal, it was there and
then it was not.
That seems counterintuitive for a contact signal, and it’s never been picked up since,
despite plenty of attempts to do so.
Perhaps the strangest aspect of Wow though is that it keeps defying explanation.
It’s never been shown to have been earth interference, or a glitch in the equipment
that picked it up.
To this day, potential explanations continue to be put on the table, only to be shot down.
This happened most recently with the hypothesis that Wow! might have been due to emissions
originating from comets, and this was widely reported in the press as a case closed explanation.
What they didn’t report as widely is that the comet hypothesis was shot down by the
scientific community very quickly.
If comets emitted that strongly at the hydrogen line, radio astronomers would have noticed
that by now and it should be easily observable.
It’s not.
So, to this day, the Wow signal remains unexplained.
Number 3 Strange Signals
While the Wow!
Signal is the most famous of the unexplained odd radio signals SETI astronomers have picked
up, it is not unique.
Other examples include a signal picked up just once, and did not repeat, from the direction
of the star TYC 1220-91-1.
What’s notable about this signal is that it appeared to originate from a nearby star
that’s very similar to our sun, and potentially habitable.
It was also at a magic frequency mathematically related to the 1420 megahertz hydrogen line.
It was also narrowband, and was observed for a full ten seconds.
But most noteworthy was that the signal was so strong, about ten times stronger than Wow!.
But, since the signal didn’t repeat and couldn’t be verified, it can’t ever be
determined if it was simply earth interference.
Other unverifiable signals include a 2015 signal from the star HD 164595, another very
sun-like star, but this time with a verified planet in orbit around it.
But it never repeated, and it happened to be in a military band, and it seems likely
that there are satellites downlinking from orbit that scientists may not be aware of.
And then there was the signal SHGb02+14a, which was weird even for a signal plausibly
of alien origin.
Firstly, unlike most, this signal repeated, having been initially observed three different
times.
And, it was at the 1420 Megahertz frequency, initially.
But then it would drift.
More, there didn’t seem to be any corresponding star system to where the signal was coming
from.
And it was very weak, and if it originated on a planet, that planet would have to have
been rotating 40 times faster than earth.
Number 2 KIC 8462852 Tabby’s Star
In 2015 a star was found in the massive amount of data collected by the Kepler spacecraft
that was behaving like no other star previously seen.
It would experience dips in brightness of up to 22 percent suggesting that something
extremely massive was passing in front of the star.
Initially, it was uncertain as to what this could be.
A cloud of dust wasn’t a good fit because star systems that have dust discs tend to
emit infrared radiation brightly.
No such radiation was found at KIC 8462852.
The star’s main investigator, Dr. Tabetha Boyajian, suggested that it could be cold
comets blocking the light.
But on further investigation, it was found that the number of comets needed to produce
the effect would have been implausible, hundreds of thousands of them.
More, another study found that exocomet signatures in the Kepler light curve don’t fit what’s
going at Tabby’s star.
Given that natural explanation after natural explanation were falling flat with this star,
the idea that gigantic alien megastructures could be blocking the light was starting to
be considered.
Now, even that doesn’t fit as later researched showed that whatever was blocking the light,
at least with the most recent dips measured from the ground here on earth, was not opaque,
and that dust in some bizarre juxtaposition around the star was the cause.
But there’s still the question of the missing infra-red.
To date, no one yet knows exactly what’s going on at KIC 8462852.
Number 1 Pryzybylski’s Star
At the time when the KIC 8462852 story was a media hit, it was often called the strangest
star in the universe.
And while it certainly was strange, this final star on our list gives it a run for its money.
The star is called Pryzybylski’s star after the Polish-American astronomer that first
studied it.
The star is what’s known as a peculiar star, a class of stars that are chemically unusual
in some way when compared to other stars.
But even then, this star stands apart because it contains elements that really shouldn’t
be there and are more at home in a laboratory on earth than in nature.
And it’s not just a handful of odd elements, it’s a lot of them, in sufficient quantities
to be detectable at great distance in the star’s spectrum.
Elements like praseodymium, ytterbium, technetium and prometheum are present, the last only
discovered through the activities of the Manhattan project.
Certainly odd, but stars can have odd elements in them.
But there’s more, the star is also anomalously low in iron and nickel, abundant elements
in the universe, but perhaps strangest of all are the very short-lived actinide elements
higher on the periodic table than uranium.
Quite a few of these are present, and it’s just weird, but one in particular raises an
eyebrow.
Plutonium.
Plutonium is thought to be produced only in minute quantities in nature, and only under
specific circumstances.
For this star to have it in abundance is a mystery, though hypotheses have been put forth
that you might be able to get to elements higher than uranium if the star were bombarded
by a neutron star, or some unknown nuclear process within the star is creating them.
But it’s worth mentioning that in 1966 Carl Sagan and Iosef Shklovski hypothesized in
their book “Intelligent Life in the Universe” that one way for an alien civilization to
announce its presence to others would be to add plutonium to its star.
Thanks for listening!
I am futurist and science fiction author John Michael Godier currently planning Halloween
episodes for both channels, this one and Event Horizon, like to that channel below.
Halloween is my favorite holiday, and I’ve been busily filling my house with dried ears
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