Are we being watched by Alien "Lurkers" in our solar system?
Are we alone in this universe? This existential question might have come up in probably everyone's
mind. Taking in mind the vastness of our universe and the large amount of star systems present in
it, we might not be alone! And if that’s the case, what if an alien civilization, that is
millions of years ahead of us in technological advancement, has already found us? What if these
aliens are lurking in our solar system? What if we are being imaged and watched by them constantly?
Is it possible that there are alien lurkers in our solar system?
In this video we will talk about whether any alien civilization can possibly watch us or not!
If you are here watching this video, it means you are passionately curious about human spaceflight
and the mysteries of the universe. We constantly strive to make videos that excite a curious person
like you, so subscribe now and press the bell notification! Back to our possibility of lurkers!
In 1950 a scientist named Enrico Fermi asked a question, “Where is everybody?” The question went
on to become one of the most famous paradoxes in History, also known as the Fermi Paradox.
Our universe has billions and billions of stars,
and those stars have trillions and trillions of planets. Considering the vast amount of planets
present in our universe, chances of finding life are quite high. So if that’s the case,
shouldn’t the universe be teeming with spaceships. Where is everybody? This is the Fermi paradox
and no one has a real answer to it. All we have are possible theories and among them is one such
theory that states that Advanced Aliens are lurking in our solar system and observing us.
Could Aliens be photographing us right now watching us go about our day, quietly monitoring
our behavior. This might send a chill up your spine and make you wonder about the science behind
this theory. Can this be really possible? Can anyone really observe us without us noticing them?
In order to watch us the aliens would need the technology to image long distances of space.
The basic challenge of imaging other star systems is the distance that exists between them.
Even the closest stars to us are so far away that they appear as mere specks of light.
Today in modern astronomy we have devised various techniques to spot and discover
planets orbiting around other star systems. Until today about 5000 exoplanets have been
discovered by various techniques used by us. This photo of the young star system, PDS-70,
is a state of the art image taken by the Alma observatory Last year. Despite this technical
achievement here, the spatial resolution of the jupiter-class in this image is very limited and
anything smaller than that cannot be resolved by us today. This is why the jupiter-type planet also
appears as only a smudge. Even if the image of the planet is resolved by a scale of 1000,
we would still only have a 1 by 1 pixel image at the very best. So you can only imagine
what kind of resolution would be required to image and observe a small planet like Earth.
On Top of that the Alma Observatory was able to detect this planet only because it formed recently
and is very hot and luminous emitting the light that we see. Our Earth is not only very small
but also very faint as compared to this planet in PDS-70. To combat these two problems of resolution
and faintness, the only typical solution is to build A Very Big Telescope. Fortunately in 2010,
Jean Schneider and his colleagues calculated the extreme limits of our technology, stating that to
take a 10 by 10 visible light image of a Super sized Earth that's just 16 light years ahead,
we would need a 70-km wide telescope. Now we don’t necessarily need a single telescope with a
diameter of 70 km, we could use a technique called interferometry, which uses a number of telescopes
to receive the light spread out over a region of 70 km. This idea was taken to the extreme
by the Event Horizon telescope(EHT) which used telescopes across the earth to famously image the
Balckhole in Messier 87, the first ever image of a Balck hole! But even using the entire earth as
a visible light interferometer would still not be sufficient to resolve exoplanets, so that we could
see the inhabitants of that planet. This would be the ultimate goal of observation of exoplanets.
Imagine a video of a distant exoplanet, so detailed that you can easily see the alien
flora and fauna of that planet. We can watch the sentient beings of the planet go about their day.
The insights possible from such a video can be truly amazing. Schneider calculated that
to have this level of detail you would need a telescope with the diameter of the sun. But that
would only solve the problem of resolution, we also need photons of those distant exoplanets.
So even with such a big telescope it would be nearly impossible to image the inhabitants of
those planets as they would be so faint that their photons wouldn't even reach us. We took the time
to explain this to you because to observe us from a distance the aliens would need this technology
and even that wouldn't be sufficient! So what other option is left on the table?
The hubble space telescope has been one of the most important telescopes for mankind
providing thrilling images of the universe. With a diameter of 2.4 meters,
Hubble cruises above the earth at 540 kilometers, which is 75 Billion times closer than the closest
star, Proxima Centauri. But if we turn around the Hubble telescope to look at the people on Earth,
the spatial resolution provided by Hubble would be plenty enough to see people go about their day.
This means that it is possible to resolve inhabitants of a planet from space,
it's just that you would have to possibly go to that star system.
This brings us to the title of this video, What if they are lurking in our solar system itself?
Mission Concepts like Breakthrough starshot aim to go to a distant planet and make observations.
Keeping in mind the limit of our telescopes this will be the ultimate goal of observations.
Given that we are curious about doing this, what if an advanced alien civilization is already doing
this to us. First suggested in 1960 by Ronal Bracewell, the idea suggests we should look
for probes inside our solar system rather than listening for radio signals from Distant stars.
These are called bracewell probes, and they might be observing Earth for millions of years in
case any intelligent life evolves. The Earth has been presenting a clear oxygen biosignature for
about 2 billion years now. These bracewell probes can even use the sun to harness their energy
and send back information about us to their home planet. As sci-fi as this idea sounds, let’s
openly explore the science behind this. So the tools that we use today to look for signals from
distant stars can easily be repurposed to look for these probes and signatures in our solar system.
And imagine if we are able to eavesdrop on the transmission being made by these lurking probes.
These transmissions might have a layer of encryption, but the fact that they were not
made for us would be thrilling. We cannot help but wonder what the transmission says, what
compression algorithm it uses. All of these things would be completely alien to us, their language,
the mathematics they use! Unless the aliens purposely want us to decipher these messages
and provide us simple data forms, they need not to be concerned about their privacy and encryption
as all the information would be completely alien to us. The mere presence of such a
probe in our own backyard would be immense which we could possibly salvage and reverse engineer.
But where will this probe be present in our solar system to silently and easily observe us?
At what place we should look for them. Let’s talk about the science behind that.
If this probe intends to take clear high resolution images of the earth it needs to be as
close to earth as possible. Low earth Orbit or LEO is the perfect place for that! But it is already
intensively monitored by humans. The US Space surveillance catalogs over 34000 orbiting objects
in orbit around the earth, with sizes as small as 10 centimeters. A probe smaller than that would be
unable to resolve human behavior on earth, so this possibility is out of the question. The presence
of a low earth orbit lurker will be challenged by our extensive monitoring of the region.
The next place we might look is our Moon. A probe on the moon would have perfectly stable gravity
and will be undisturbed by atmospheric erosion, weathering or any geological activity. However,
like Low Earth Orbit almost every part of our moon has been extensively photographed by orbiters over
the last few decades. The lunar reconnaissance orbiter imaged the moon's surface at a spatial
resolution of 100 meters. So if there was a 100 meter sized alien telescope on the lunar surface
we would have spotted it by now or it is very small. In order to image the earth’s surface
to observe its inhabitants it would need much more than that. So if the moon is out of the
question what’s left? Co-orbital asteroids and quasi satellites might be our next best hope.
Cruithne is a particular interesting possibility! It's a two-kilometer-sized co-orbital asteroid
that follows a horseshoe orbit that takes it as near to the Earth as 12 million kilometers
once every 770 years. Even if the full two kilometers of this asteroid were some kind of
enormous extraterrestrial telescope monitoring the world, it would still be restricted to a spatial
resolution of no more than four meters of the earth's surface, and this would only happen at
these rare and occasional periods of closest approach. And this really isn’t sufficient.
However Cruithn is just one of several other co-orbitals. What if these various different
asteroids form an interferometric network. These co-orbital objects are considered to
remain stable over thousands of years, but not millions, and they move in unpredictable, nearly
chaotic orbits with regard to one another, making interferometry a nightmare. Extraterrestrial
lurkers hidden amid these co-orbitals are not an obvious and obvious option or alien. With
numerous significant difficulties with earth orbits and co-orbitals being unstable,
it's possible that the lurkers would pick a more distant vantage point where the earth's gravity
will not destabilize their probe. But that would require a truly enormous space probe, for example,
To visually photograph the Earth at one meter resolution from a vantage point near
Saturn's distance, a telescope roughly the size of our moon would be required.
Of course, aliens could use the interferometric approach but now the vast survey region would
have to scour and the sheer faintness of these probes would make them presently unobservable.
Put together, The case that there is an unknown alien lurker
imaging the earth at high resolution and visible wavelengths is quite unlikely.
But anything can happen. So what do you think about the possibility of aliens watching us?
Would they care to make such an over-engineered system just to observe us?
Let us know what you think in the comment section below. There will be more updates coming about
these Extra-terrestrial beings from both SETI and METI. So make sure you subscribe to the channel
and don't miss out on all the interesting updates about astronomy and spaceflight.