Something Weird Is Happening On Venus..

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Episode Transcript

(00:00):
Something weird is happening on the planetVenus. We know that Venus is the
most earthlike planet in the Solar System, practically our twin sibling, So in
theory this place should be very familiarto us. But in reality, Venus
is so incomprehensibly strange that we stillunderstand very little about the true nature of

(00:21):
this planet. So are we lookingat a vision of the future, the
nightmarish end that awaits all planets,or is Venus a memory of our past,
of a time when the Earth itselfwas a young, hot volcanic wasteland.
The real secrets lie beneath the surfaceand above the clouds. This is
the mystery of the planet Venus.We know that there are many similarities between

(00:46):
Venus and the Earth. Both planetsare very similar in size and mass,
they have the same rocky composition,They orbit in a relatively similar proximity to
the Sun. But one of thesestranger similarities between the two planets is that
both both Venus and the Earth havea young, rejuvenated surface. So what
do we mean by that? Well, if you look at the surface of

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Mars Mercury or Earth's moon, you'llfind a dense pattern of impact craters.
These are the remnants of multi billionyear old asteroid impacts that occurred when the
Solar System was young and still fullof rocky leftovers from the formation of planets
and moons. The Earth was notspared from this ancient bombardment. Our surface

(01:29):
would just be as pockmarked as theMoon if not for the continuous rejuvenation of
plate tectonics. The Earth is constantlyrecycling mass from the surface down into the
mantle and creating new land through volcaniceruptions. The surface of Venus appears to
tell a similar story. The ancientbattle scars have been wiped away, leaving

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the age old Venusian surface at somewherebetween three hundred million and one billion years
old. Except Venus does not haveplate tectonics. Instead, it has one
continuous and stagnant lid of rock thatsurrounds the entire globe. So there's no
easy explanation as to how the entireplanet has been resurfaced in such a relatively

(02:15):
small amount of time. Even onebillion years on the cosmic scale is fairly
young. You don't need tectonic platesto have volcanic activity, and this is
how we identify that Venus has astagnant lid. For a surface. On
the Earth, active volcanoes are concentratedalong the borders between the tectonic plates,
while on Venus there are thousands ofvolcanoes spread out across the surface in a

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seemingly random distribution. This would indicatethat volcanoes simply spring up at any location
where the surface crust is thin,and that their formation is not driven by
physical movement. We have evidence thatvolcanic activity on Venus continues to the present
day, but this still doesn't fullyexplain the re surfacing event. Planets with

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a stagnant lid will have lower overallvolcanic activity than similar planets with tectonic plates.
On the Earth, volcanoes sweep backand forth across the surface over millions
of years, violently reshaping the landas they go, while on a planet
like Mars, volcanoes just sit inthe same place for millions of years,

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slowly and steadily erupting until they formgigantic mountains like Olympus Monds, the highest
peak in the Solar System. Actually, most of the highest mountains in the
Solar System are located on Mars.Thanks to its stagnant lid and stationary volcanoes.
You would think that a similar thingwould happen on Venus, but that's

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not been the case. It doeshave a couple of very tall mountains,
but overall the surface of Venus ismuch closer to Earth than it is to
Mars, which still leaves us wonderingjust what the hell happened here. One
of the more interesting theories about theresurfacing of Venus is that it all happened
fairly abruptly in an explosive global cataclysmicevent. The idea is that the stagnant

(04:06):
lid of the Venusian surface probably trapsin a lot of pressure underneath the surface,
and since Venus is pretty close tothe Sun, much closer than Mars,
there is the likelihood that a lotof thermal energy could build up inside
the planet over hundreds of millions ofyears, and eventually this pressure is going
to reach a point where it can'tbe contained any longer, releasing as one

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catastrophic global volcanic eruption. If Venusdid burst like an overfilled balloon at some
point within the past billion years,this would explain everything that we see on
the planet today. After the volcanicpressure release, the planet would cool back
down into a freshly resurfaced globe.Unfortunately, this cataclysmic event permanently erased any

(04:51):
surface evidence of the ancient past onVenus. When we look at the planet
Mars, we know that there wasa time when liquid water flowed over the
surface in ancient rivers, lakes,and even oceans. If a relatively small
and cold planet like Mars could supportthe necessities of life, then it stands
to reason that Venus probably could havedone the same. In order to find

(05:13):
the proof, we need to moveup. We know that the atmosphere on
Venus is incredibly hostile. We knowthat is caused by a runaway greenhouse effect,
but we're not entirely sure how itgot that way. To begin with,
the surface pressure of Venus is ninetytwo bar. That means the air
is ninety two times more dense thanwhat we find at the surface of the

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Earth. The majority of the Earth'satmosphere is actually composed of nitrogen, one
of the most common elements in theknown universe. It accounts for around seventy
eight percent of the air. Oxygenis only around twenty one percent, and
the remaining one percent is mostly aninert noble gas called argone, and zero
point four percent of the Earth's atmosphereis occupied by greenhouse gases like carbon dioxide,

(06:00):
methane, and ozone. Interestingly enough, we know that Venus has around
the same massive nitrogen in the atmosphereas Earth does, and there are even
detectable amounts of molecular oxygen on Venus, but that is all dwarfed by an
unfathomable amount of carbon dioxide. Inthe Venusian atmosphere, it makes up over
ninety six percent of the total compositionand at ninety two bar of density,

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that is a lot of carbon dioxide. But where does it all come from?
The Earth manages its own carbon dioxidethrough a natural cycle. CO two
is absorbed by plants, they die, they fossilize, and then plate tectonics
eventually pull the fossils down deep intothe mantle. Then humans came along and
started burning the fossils and putting themstraight back into the atmosphere. But that

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likely wasn't the case on Venus,and it's also not likely that Venus just
happens to have a massive amount ofexcess CO two that the Earth does not.
As far as we can tell Venusand the Earth started out as nearly
identical balls of molten rock. Thechemical composition should be more or less the
same, meaning that some kind ofnatural force moved all of the excess carbon

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from the inside of the planet tothe outside and created the runaway greenhouse effect
that has superheated the planet's surface.This could have happened during the planet wide
cataclysm. That would be a reasonableexplanation, meaning that Venus hasn't actually been
what it is now for all thatlong. Venus is closer to the Sun
than the Earth, but only byaround thirty percent, which is not enough

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to cause a huge difference in temperature. If you take the excess atmosphere out
of the equation, the average surfacetemperature of Venus would be around seventy degrees
celsius, which is still too hot, but it's as close to Earth temperature
as we would ever find anywhere inthe Solar System. In fact, it's
very likely that there was a timewhen the atmospheric conditions of Venus were very

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similar to the Earth, complete withlarge amounts of liquid water. Now,
like we said earlier, any geologicalevidence of flowing water is long gone from
the surface of venus, but thechemical evidence does remain. This comes in
the form of an atom called deuterium. Okay, stick with me here.
Deuterium is an isotope of hydrogen,which basically means that deuterium is a unique

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variant of hydrogen that is created bythe addition of a neutron inside the core
of the atom. Typical hydrogen onlyhas one proton in the nucleus, while
deuterium has a proton and a neutroninside the nucleus. This gives utium a
heavier atomic weight than hydrogen, andon Earth there is typically one deuterium isotope

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for every six thousand, four hundredand twenty atoms of hydrogen. Here's the
payoff. The concentration of deuterium atomson venus is significantly higher, meaning that
at some point there was a massiveamount of hydrogen that dissipated into space and
left behind its heavier isotope variance.This is a smoking gun indicator of a

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water boil off event. The waterboiled into steam, and the lightest hydrogen
atoms in that steam floated all theway up into the atmosphere and were carried
away by the solar wind, whilethe heavier atoms remained trapped somewhere in between.
So in this way, when welook at Venus, we are seeing
a likely future for the Earth.We often use Mars as an example of

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a dead planet because its geological activityhas ground to a halt, the atmosphere
has dissipated, and the average surfacetemperature has dropped below freezing. But this
is more like a planetary coma deathis still to come. We live next
to a gigantic nuclear fusion reactor thatis gradually increasing in power right up until

(09:52):
the hydrogen fuel source is depleted.Our Sun won't explode when it dies,
but it will expand outward to becomea red giant, which will then eject
its corona and collapse into a whitedwarf star surrounded by a nebula of matter
that used to be our solar system. Long story short, In the end,
everything burns. The Earth will notgo quietly into that good night anyway,

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nihilism aside. Our own planet willgradually, over billions of years,
start to look a lot more likeVenus, so we can kind of reverse
engineer the process. It's likely thatthe water boil off comes first. The
Earth's magnetic field won't last forever.We're not sure if Venus ever had a
magnetosphere or if it just dissipated veryearly on, which would explain the planet's

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short lifespan. Loss of the magneticfield allows the atmosphere to thin, end
hydrogen to escape. Lower atmospheric pressure, combined with a hotter sun, means
that water evaporates much faster and failsto recondense into rain. With no water,
the surface of the Earth gets dryand stiff, which is probably what
brings an end to plate tectonics andcauses the outer trust to solidify into a

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stagnant lid. Now, thermal energybuilds up under the sealed crust of the
Earth until it pops like a balloon, and the entire surface is engulfed in
volcanic activity, spewing massive amounts ofheavy carbon gas into the atmosphere to form
dense clouds that cling to the planet. And just like that, the Earth
five billion years in the future wouldbe largely indistinguishable from the planet Venus as

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we see it today, unless throughreverse engineering Venus' demise, we can somehow
figure out how to stop our planetfrom sharing the same fate.