Thanks to Masterworks for
sponsoring today’s video. Is a world like Pandora possible? This question
was buzzing in my head as I left a recent screening of the movie Avatar: The Way of Water.
I’m sure a lot of you have seen Avatar or its sequel, or at the very least heard about them. But
in case you’ve been living under a rock, or there weren’t any cinemas on the desert island where
you were shipwrecked, here’s the short version. Both Avatar movies are set on Pandora, an
Earth-like moon in the Alpha Centauri A system. After Earth exhausts nearly all of its natural
resources, humans set their sights on colonizing Pandora, which hosts highly developed ecosystems
of interconnected lifeforms, among them, a species of technologically primitive but physically
evolved humanoids called the Na’vi. There is, of course, a lot more to it – interstellar travel,
genetic engineering and memory implants, all of which are really interesting. But this video is
concerned with the science of Pandora itself. How much is based on real science? What did
director James Cameron and his team get right? What did they get wrong? And, although it might
sound farfetched, could there theoretically be a world like Pandora out there? I’m Alex
McColgan, and you are watching Astrum. Join me today for a fun thought experiment, as we turn
our telescopes to the fictional world of Pandora, and analyse the moon’s complex geology,
orbital mechanics, biosphere and atmosphere. Let’s start by looking at the Alpha
Centauri A system where Avatar is set. Alpha Centauri is a three-star system in the Milky
Way Galaxy, comprised of 2 sun-like stars (Alpha Centauri A and B) and a small red dwarf (Alpha
Centauri C, also known as Proxima Centauri). As the closest neighbouring star system to our
own, it’s a convenient place to visit. Of course, in interstellar terms, convenience is relative. Alpha Centauri is 4.37 light years away from
Earth, meaning it would take a spaceship travelling at the speed of Voyager 1 over
70 thousand years to get there. But let’s assume humanity develops technology capable
of interstellar spaceflight, as it has in the Avatar movies (even though the original’s start
date of 2154 still might be a bit optimistic). Alpha Centauri A actually has a few things going
for it as far as habitability is concerned. Its star is only a bit bigger and brighter than our
Sun, meaning it has a Goldilocks Zone – not too hot, not too cold – around 1.2 Astronomical Units
from its centre, where liquid water could exist on rocky worlds orbiting it there. A good start for
the science of the film. But despite Pandora’s Earth-like appearance, one notable difference is
that it isn’t a planet. It’s a moon orbiting the hypothetical gas giant Polyphemus. Here, too, the
films are on a pretty sound scientific footing. There are most likely many more moons
than planets in the Milky Way Galaxy, meaning the chances of finding a moon with the
right conditions for life are that much greater. And even within our own Solar System, we know of
several moons that could be hospitable to life. Two of those, Europa and Ganymede, orbit
Jupiter, a gas giant like Polyphemus. Enceladus, which orbits Saturn, is another. But
on all these moons, any potential life would exist in the oceans that we think lie underneath
their frozen surfaces. Pandora, on the other hand, has Earth-like oceans on its surface, which
are on full glorious display in Avatar: The Way of Water. And any surface life would
likely face significant challenges. Gas giants have intense radiation belts made of electrons and
ions trapped by their strong magnetic fields. So, any life on Pandora’s surface had better be up to
the task of dealing with some serious radiation. There might be offsetting factors, though, such
as a buffer from its atmosphere. Pandora could also have its own magnetic field for protection,
and there’s some evidence for this explanation. We see indirect evidence in the form of aurorae
and the film’s floating Hallelujah Mountains (both of which I’ll discuss in a bit, so hold that
thought!) Avatar’s fan wiki proposes the alternate explanation that Pandora resides outside the main
radiation belt, except for one week when it passes through Polyphemus’s night side. Allegedly, this
is when the aurora occurs on Pandora. Whether or not this was James Cameron’s intention, it seems
that Pandora’s life has evolved to survive in a particularly harsh environment, and I, for one,
wouldn’t question the toughness of the Na’vi! In real life, we have yet to confirm a gas
giant orbiting any of the Alpha Centauri stars, although there is some debate as to whether
a possible giant dubbed Candidate 1 might be orbiting Alpha Centauri A. Candidate 1 was first
spotted using mid-infrared imaging technology in 2021, which is over a decade after
the first Avatar movie came out. Incredibly, scientists believe it would orbit
right in Alpha Centauri A’s habitable zone. But before you get too excited about the discovery of
a real-life Polyphemus, be aware that scientists still aren’t sure if it’s really an exoplanet
or just an artefact caused by a cloud of dust. If it is a planet, it would likely have at least
the mass of Neptune – in other words, a gas giant. We’ll have to await further evidence
to evaluate this one. But in 2016, scientists discovered something just as cool
orbiting in Proxima Centauri’s habitable zone: a planet that is Earth-like in size! Seeing as
Proxima Centauri is a really old and tiny star, there is, however, debate surrounding
how habitable this world really is. Our ability to detect exoplanets has gotten way
better in recent years and continues to improve, so it’s likely we’ll continue to find exoplanets
that are potentially habitable. Regardless, whether or not Alpha Centauri A has a planet
like Polyphemus isn’t crucial to this exercise. Polyphemus could exist anywhere in the
universe as far as we’re concerned. One of the more unusual aspects of the Avatar
movies is how they handle Pandora’s day-night cycle. In both movies, there is a night-like
phenomenon referred to as “eclipse” by the Na’vi. This is showcased spectacularly, as Pandora’s
inhabitants experience an ethereal twilight when the moon enters the shadow of its parent planet,
Polyphemus. This is a rather beautiful bit of world-building, as Pandora would likely experience
a regular darkening event, like our rarer total solar eclipses on Earth, which would coincide with
the eclipse of Alpha Centauri A behind its parent planet. These eclipses would probably be
experienced as a relatively short darkening, while a second, longer night phenomenon
would occur due to the moon’s rotation. I also love how night on Pandora takes on
a twilight appearance. This makes sense, given the relative proximity of Alpha Centauri B,
which would still be an extremely bright star when Alpha Centauri A is occluded. When you factor in
the bioluminescence of Pandora’s many florae and fauna, what you get is a shimmering, twilit world
with enough scientific grounding to pass muster. As for how long night lasts on Pandora,
James Cameron has yet to spill the beans, but there’s some interesting speculation
among the film’s devoted fan base. Avatar’s fandom wiki conjectures that Pandoran
eclipses are 100 minutes long , and nights are 34 to 35 hours . Since Pandora is probably tidally
locked to Polyphemus, it might take just 60 or 70 hours to complete its orbit. (Remember, when a
moon is tidally locked to its parent, like ours is, its orbital period and rotation are the same
duration, which is why we always see the same side of the moon from our standpoint on Earth.) Io
orbits Jupiter in 1.8 Earth days, for instance, so a 60-hour Pandoran orbit isn’t out of the
question. This leads to a fascinating inference: if you are on the side of the moon that sees
Polyphemus, it will always be in the same place in the sky, whereas on the far side of Pandora,
you won't see the planet at all – or any eclipses. So, any natives living on the far side might
not even know they’re orbiting a planet! If any of you have your own theories
about Pandora’s day-night cycle, please let me know in the comments. Your guesses
might be better than the ones I was able to find! Next, let’s talk about Pandora’s atmosphere.
According to the films, it is a mix of nitrogen, oxygen, carbon dioxide, xenon, methane, ammonia
and hydrogen sulphide. Unfortunately for humans, the latter three are unbreathable. And the high
quantities of carbon dioxide (allegedly 16 to 18%) are also a no-go for humankind. But humans
developed under the unique atmospheric conditions of Earth. Theoretically, life under Pandora’s
alien conditions would evolve differently. I appreciate that the movies put a lot
of thought into this. It’s addressed with the anatomy of the Na’vi, who
have special organs called Wichow, which combine carbon dioxide with water
and convert them into oxygen and methane. Despite Pandora’s high CO2 levels, it also has
higher levels of oxygen than Earth’s atmosphere. Combine this with the oxygen generating wichow and
the Moon’s 20% reduced gravity compared to Earth, and you can see why the fauna on Pandora grows so
big and strong. More oxygen in the atmosphere in the ancient past is why dinosaurs got
to grow so tall on Earth, after all. Another interesting fact is that Pandora’s
heavier mix of gases and denser atmosphere at sea level means acceleration requires more force.
Humans would experience this like a wind blowing against them as they walk, whereas the Na’vi are
equipped to overcome this resistance with thin, muscular frames and tensile toes for gripping
the ground. Pandora’s unique atmosphere manifests in other ways, too. My absolute favourite touch
is the aurorae that appear in The Way of Water, which appear bluish and violet. On Earth, most
aurorae are green, which is the product of solar winds exciting oxygen and nitrogen molecules under
a given set of barometric conditions, although we do rarely get red, violet or even yellow auroras.
It’s no surprise that these phenomena might look different on Pandora. On Jupiter and several
of its moons, for example, aurorae are blue, while on Saturn, they are largely in the
ultraviolet and infrared bands of the spectrum. On Pandora, these different colours could be a
result of differences in atmospheric composition, pressure and the strength of its magnetic
field. So far, I’m actually surprised by how much of Pandora is pretty plausible! But I
know there’s a question you’re waiting to ask, so let’s get down to it: how realistic are the
film’s iconic floating “Hallelujah Mountains”? Well, there’s good news and bad news. The
good news is physicists at Yale and Penn State say floating masses produced by magnetic
repulsion could, theoretically, be possible. Unfortunately, you would expect this phenomenon
to require extremely low levels of gravity incompatible with the locale’s iconic waterfalls
and with how gravity is generally represented on Pandora. But there could be another explanation.
After all, the mountains are rich with Pandora’s iconic precious metal unobtanium, which
is described as a powerful superconductor. In fact, the prospect of mining unobtanium is
what brings humans to Pandora in the first place. In theory, if there were a magnetic bubble
on the moon’s surface, this could produce an effect in the unobtanium-rich mountains similar
to how maglev trains float above their tracks. Given that unobtanium is a theoretical
metal, I’ll give this one an incomplete. Are floating mountains likely? Not exactly, but
we should at least leave the door open to such a phenomenon being possible. Having said that,
the Hallelujah Mountains are based closely in appearance to the mountains of China's Zhangjiajie
National Forest Park, minus the floating part, so if you want to see the closest thing
to Avatar’s most spectacular feature, you might want to book your next ticket
to Zhangjiajie. So, there we have it, a walk-through of some of Pandora’s likely,
not-so-likely and seemingly impossible attributes. Overall, I’m really impressed with how well
Avatar held up to this thought experiment. James Cameron has said on several occasions
that Avatar is meant to be a space fantasy, but for a fantasy, it’s one that clearly has a
lot of thought and research put into it. When you factor in the film’s important message about
ecological preservation, there’s a lot for the scientific community to embrace and appreciate.
And who knows, maybe future discoveries will make some of Avatar’s more outlandish predictions look
prescient? I’m looking at you, floating mountains! In Avatar, travelling to Pandora is a
multi-billion dollar industry. Our own space industry pales in comparison, making the
film’s start date of 2154 a little optimistic. Luckily, one company is already making
technological innovations in a global market. And what they’re doing could actually
help you manage last year’s impact on your own investments. Because with Masterworks, almost
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to purchase. Masterworks’ team has built a massive art database, tracking records from auctions
spanning decades. They purchase the art up front, store it for 3-10 years, and if the painting sells
for a profit, you receive your share. In fact, from every one of their 11 exits to date,
Masterworks has delivered over 9% net returns to their investors, with their last three
exits returning 10, 14, and 35 percent net. To keep up with demand, they release
new offerings on the platform regularly, but there is also a wait list to keep new
offerings from selling out too quickly. Luckily, you can skip Masterworks’ wait list right
now, with the link in the description. Want to see more deep dives into the science
behind other fictional worlds? Let me know in the comments. A big thanks to my patrons and
members for your support, and especially this week to GDeath for contributing $25, thank you I really
appreciate it. If you want to support too and get access to the new rewards, check the links in the
description. All the best and see you next time.
