Stand by.
We are now entering the atmosphere of Venus.
Attention.
Before the first space programs
of the 20th century, it was thought
that our closest neighboring planet may harbor life.
I can remember there are images where there are dinosaurs
and flying dinosaurs.
Thick clouds covering the surface of Venus
caused humanity's imagination to run wild,
and for good reason.
So at first glance, Venus and Earth are quite similar.
They are about the same size and about the same mass.
And in fact, sometimes Venus is called our sister planet.
But the first probes
set by the Soviet Union and NASA discovered a world
plagued with a poisonous greenhouse atmosphere,
a sweltering surface temperature
and a crushing air pressure.
The Venusian surface has a temperature
of over 450 degrees Celsius, so lead essentially melts
on the surface of Venus.
It's very hostile.
And so attention turned
to our more hospitable neighbor, Mars,
leaving Venus largely neglected for decades
but never forgotten.
Scientists long speculated that microbial life could exist
in the permanent cloud-layer atmosphere.
It turns out that in the upper layers of the atmosphere
between 50 to 60 kilometers above the surface,
we found conditions which are not that different
from the surface condition we find on Earth.
Then in 2020, evidence of biomarkers,
potential signs of life, were detected in that cloud layer.
It may be the case that microbial life has adapted,
has evolved in order to survive in the high clouds of Venus.
And although the claim was later disputed,
it reinvigorated an enthusiasm for Venus.
And scientists are proposing multiple missions
with a single objective.
We can just pick one thing and go for it.
And we can also work on the taboo topic
of the search for life.
The Soviet Union's Venus missions
gave us the first landings and images of the surface
of another planet,
the first audio recordings from the surface
of another planet
and the first, and so far the only,
planetary balloon missions.
Balloons have already been flown
in the Venusian atmosphere, the Vega I and II balloons.
So we know it works.
In 1985, the two spacecraft called Vega I
and Vega II arrived at Venus, both equipped with landers
and balloons to explore the cloud-layer atmosphere.
The balloons separated from the crafts
lasted more than 46 hours while taking measurements.
The data from that upper cloud layer differed greatly
from the hellish surface.
So the winds have speeds of about 350 or 360 kilometers
per hour.
That's about the speed of a bullet train
and corresponds to the fastest winds we have ever measured
on Earth.
If we only look at temperature and pressure,
the conditions are very similar to the surface conditions
on Earth.
However, the clouds, which on Earth consist of water vapor,
they're actually made of sulfuric acid.
So we are looking for life which can survive
in an extreme environment.
The cloud layer
is estimated to be 50 to 100 times drier
than the driest place on Earth, the Atacama Desert in Chile.
Dr. Armando Azua-Bustos, an astrobiologist
and Atacama native has spent much of his career
looking at whether life can exist in extreme environments.
These organisms are called extremophiles,
life that is adapted to survive in harsh environments,
like a desert with no known water source.
The near-sterile environment of the Atacama
is normally used as a testing bed for finding life on Mars.
But the clouds here could give us clues
about life on Venus too.
But the Venusian atmosphere isn't just dry.
It's extremely acidic.
The Cave of the Lighted House in Mexico
contains toxic amounts of sulfuric acid.
Yet, microbial life has evolved
to use other chemical processes to obtain energy
other than photosynthesis.
While we've been learning a lot
about extremophiles on Earth,
we've also continued to learn more about Venus
since those early missions.
Now, in terms of knowledge of Venus,
today, we know much more about Venus
such as about the existing of prebiotic components
such as ammonia and hydrogen cyanide.
We also know that the greenhouse effect on Venus
started about 1 billion years ago.
So we know a lot more things about Venus
thanks to many missions which went to Venus
such as orbital missions in the past decades.
Very small amounts of oxygen
were detected in the atmosphere
by at least two different separate independent probes.
And it's amazing because we also don't know
how oxygen would be made on Venus at the levels found.
And there's sort of enough puzzles
that something really interesting is happening on Venus.
Recent probes to Venus
like the European Space Agency's Venus Express
and the Japanese Aerospace Exploration Agency's Akatsuki
has given us a lot of valuable science.
But only Mars has had missions
specifically looking for organic compounds,
the ingredients for life.
Then in 2020, this happened.
It's an extraordinary possibility.
Living organisms floating in the clouds of planet Venus.
There may be some form of life on Venus.
This gas is called phosphine.
Now, what exactly is it?
Do we have any idea?
A team led by astronomers in the U.K.
reported seeing the spectral signature of phosphine
in telescope data.
Phosphine's very unusual because on Earth
it's only associated with life,
either bacteria in oxygen-free environments like wetlands
or made by humans as pesticides and other chemicals.
Suddenly, there was a potential biomarker for life
in the Venusian atmosphere.
And this really changed a little bit the picture
of astrobiology research in our solar system.
While some groups have disputed the claim
saying that the phosphine signal isn't there
or at least at levels less than previously thought,
it's reinvigorated the interest in Venus from the public
and scientific community.
So despite all this controversy of phosphine,
people have started to relook at the old so-called
legacy data from the American and Russian probes
that went into the Venus atmosphere in the late '70s
and early '80s.
And what's very intriguing is it looks like there's evidence
for phosphine from that old data.
One thing everyone can agree on
is the need for more research into Venus.
NASA and the European Space Agency recently green lit
three separate missions.
VERITAS will map the planet's surface and DAVINCI+,
the second NASA mission, will have an orbiter to image Venus
in the ultraviolet and infrared light,
and will send a probe through Venus's atmosphere,
while the European Space Agency's Envision
will take high-resolution radar images
of the planet's surface.
Although these missions will give us a lot of valuable data,
none of them are dedicated solely to finding biomarkers.
In order to really determine whether there is life,
we need to go there.
And for us, the question was immediately,
how can we quickly develop and launch a mission
in order to determine whether there's really life
in the Venusian atmosphere or not?
And within two weeks after the announcement
of the potential discovery of phosphine,
we published a report on this mission study
to deploy a fleet of balloons in the Venusian atmosphere
and to search for life.
Balloons are used for scientific studies
on Earth due to their cheap cost, simple design
and ability to stay in the atmosphere
for a long period of time.
You can buy high altitude balloons
for maybe a couple of hundred dollars or euros.
They tend to be fairly robust so you just launch them
and then you can essentially forget about them.
And these are two benefits which are also applicable
to the Venusian context.
And considering the technology already exists,
it could be launched quickly.
Venusian balloon, which consists essentially
of two basic elements,
so one is the balloon sphere
and then we have what we call a ChipSat.
So it's about the size of a credit card.
And we have a very small payload such as a tiny camera
or small microscope on board and all the subsystems
such as power supply and communications, et cetera.
So far, this proposal hasn't made it
to the hardware phase yet,
but a separate study headed by Professor Sara Seager at MIT
and funded in part by Breakthrough Initiatives
is looking at three separate missions,
the first one to launch via Rocket Lab's rocket
as early as 2023.
We're really, really, absolutely thrilled
that we have a mission to Venus.
We've partnered with Rocket Lab to supply the scientist,
science team and science instrument.
And there's room for like a tiny instrument,
less than 1 kilogram, that will go on the probe,
and the probe is going to drop through the atmosphere
very quickly.
So the probe would last maybe an hour.
And going through the cloud layers that we care about,
that will be about three minutes.
So this mission is short,
and the instrument that the team chose,
it has a kind of complicated name.
It's called an autofluorescing nephelometer.
Autofluorescence refers to the fact
that we're basically shining ultraviolet light
on the droplets and looking for any fluorescence
that, in other wavelengths, other colors of light.
And then nephelometer is just a fancy word for an instrument
that measures the light that's scattered from particles.
If you have a black light, and you're out in the desert
and you shine it on a scorpion,
the scorpion lights up green colored,
just like my piece of fluorescent plastic.
And that demonstrates how organic compounds, life compounds,
could be found on Venus with fluorescence.
The instrument, which in its final form
will fit inside of an estimated half-kilogram payload,
will be the first attempt on Venus
to specifically look for biomarkers.
This instrument by itself is not going to be able
to definitively determine that there's life on Venus.
But if we detect organic compounds in the cloud droplets,
it's an indication that there might be life.
If what they find looks promising,
their next mission would be a balloon mission
to look for biomarkers in different areas of the atmosphere.
We envision a balloon.
And we have a few very, very specific things
we want to measure.
We'd like to remeasure the gases that don't belong,
including phosphine and ammonia and oxygen.
We'd like to check out these droplets in more detail.
In particular, we want to measure the acidity
of the droplets because there's some new theories out there,
including one from my team,
that the droplets aren't all uniform
and that they're not all incredibly acidic,
that some might be a more friendly acidity to life.
And we'd also like to measure more details
about the composition of the droplets,
measure that directly, not just from light scattering.
And if there are promising discoveries
from that mission, to ultimately prove microbes are present,
they're proposing a third mission.
We would go to Venus with a balloon
and this balloon would have a miniature rocket
attached to it.
And we would collect samples.
So we'd condense the cloud particles,
and we would trap some air on Venus, some of the gases.
And we would package those, get it inside the rocket,
which would launch from the balloon.
And it would intercept with an orbiter
that would then be able to act as a cruise vehicle
to come home to Earth with these precious samples,
so that here on Earth, we could use our very sophisticated
and exquisite instruments to look for life.
These missions
would be the first balloon missions
to look for life on another planet,
but probably not the last.
There are people who have been trying
to get a balloon mission to Venus for decades actually.
It's not like we came and had all these brilliant ideas.
We're obviously standing on the shoulders
of people before us, you know, people who are still working
on such missions.
But with the rise of private space companies
and the miniaturization of technology,
inexpensive balloon missions like these
could solve mysteries faster and make space more accessible.
There's a basic human urge to find out if we are alone,
but it's also of tremendous importance if we think about
if we would find life on Venus,
did it have the same origin as life on Earth
or did it really emerge in parallel?
And this has huge implications also for us as humanity.
Every society in human history
appears to have had astronomy as part of its culture.
And that is about wanting to know and explore
what is beyond Earth.
And today that question, you know, includes,
is there life out there?
I think it's part of wanting to understand our place
in the universe.
Are we alone?
Are we unique?
Or is the universe filled with other life forms?