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Is there life on Venus? Quantum astrochemist Clara Sousa-Silva makes the case for a new way to seek and possibly discover habitable planets — and shares her research into a poisonous, smelly molecule that might signal life beyond Earth.
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It’s my job to find aliens,
so as you might guess,
I spent a lot of time thinking about them,
imagining little green women
meeting up with their friends,
commuting to work.
And that gets me thinking
about alien astronomers
trying to find us in their night sky.
If these alien astronomers
had looked in our direction
in the last century,
they would have been really excited
to detect unequivocal signs of technology.
But what if they looked
ten thousand years ago,
before we showed signs of civilization?
Would they shrug in disappointment
and go look elsewhere for life?
No, and neither should we.
Instead, we can look
for other signs of life.
For example, if those alien astronomers
had looked our way 10,000 years ago,
they might notice that even
without signs of civilization,
we still looked slightly unusual.
For one, we have
a thick and temperate atmosphere,
but more notably,
we have suspiciously large amounts
of oxygen in the atmosphere.
This would be a really encouraging
sign of life for my alien colleagues
because the composition
of the Earth’s atmosphere
can only sustain itself
through a biological cycle.
So can we do the same to them?
I’m certainly trying.
I am a quantum astrochemist,
which means I study
the quantum interactions
between molecules and light in space.
We can’t see these molecules
or even the planets they’re on.
But when life from a star
goes through an alien atmosphere,
each molecule within it
leaves a unique fingerprint
in the starlight that I can see from here.
And I look for the fingerprints
of molecules that could
be associated with life,
or biosignatures,
like complex pollutants or oxygen.
In the context of Earth,
oxygen is a wonderful biosignature,
but oxygen is not that hard to make.
So, for example, if our sun
had different levels of radiation
or if our oceans were evaporating
from a runaway greenhouse effect,
then large amounts of oxygen
could accumulate in our atmosphere
without biology,
and then oxygen would be
a false positive for life.
So maybe oxygen won’t be the solution
to finding life beyond Earth,
but then what is?
Well, my specialty
is to look for unusual molecules
that have fewer false positives for life
because they’re so difficult to make
that they’re rarely made spontaneously.
And my favorite of those
unusual molecules is phosphine.
When I first started working on phosphine
about a decade ago,
people had a hard time
thinking of it as a biosignature at all.
Instead, it was known
for being this horrific,
foul-smelling molecule
that messes with life’s
ability to use oxygen,
making it a really effective killer.
Because of this fatal interaction
with oxygen metabolism,
phosphine is used widely as a pesticide
and sadly for the same reason it was used
many times in chemical warfare.
Phosphine can be made in the lab,
and it’s also produced
in the extreme environments
found inside gas giants
like Jupiter and Saturn.
But on rocky planets like the Earth,
it is rarely created accidentally.
So we don’t really expect
to find phosphine on Earth at all.
And yet we do.
We find it in small amounts
throughout the globe,
and in some places
in strangely large quantities,
places like swamps
and rice fields and lake beds
and the excrements and guts
of most animals.
And what all of these
ecosystems have in common
is that they all host organisms
that are not reliant on oxygen,
so phosphine can’t hurt them.
Indeed, phosphine seems to be safely
and enthusiastically produced
in all of these oxygen-poor ecosystems.
So I figured, maybe other planets
with life less reliant on oxygen than ours
could also have phosphine,
but as a really popular biosignature.
And here’s the best thing about phosphine.
Because it’s so hard to make
on rocky planets like the Earth,
it has almost no false positives for life.
So I started considering
what telescopes we would need
to detect phosphine on planets
in our galactic neighborhood.
Because if we did,
I predicted it could only mean life.
I was imagining a distant planet,
a oxygen-poor tropical paradise
with a phosphine-rich biosphere
that we might one day be able to detect.
But turns out phosphine
was a little more exciting
than I had initially envisaged
because a few months
after I finished this work
an astronomer, Jane Greaves,
reached out to me
asking for help with interpreting
a telescope signal seen here in white.
Then months later,
another signal, seen here in orange,
that seemed to indicate that phosphine
might be present not on a distant planet,
but right next door,
on the clouds of Venus.
So did we do it?
Did we find life beyond Earth?
We don’t know.
These Venus observations
were noisy and preliminary,
so we still need to confirm,
without a doubt,
that the signal is real,
and if it is, we need to make sure
it’s not another molecule
mimicking phosphine’s fingerprint.
And if it is unambiguously phosphine,
we still need to figure out
what or who is making it,
because maybe it’s true
that life is the best explanation
for the presence of phosphine
on a planet like Venus.
But maybe that’s wrong
and there’s an exotic but not biological
way of making phosphine
that no one has thought of yet.
Either way, as much as I love phosphine,
I don’t think that’s how we’ll find life.
The detection of life will likely
not come from a single molecule.
No matter how special it is.
We’ll have to detect a whole biosphere
producing a complex network of gases
that together form a message
that reads: “We’re alive!”
As the Venus story shows,
the detection of life
will likely be uncertain,
but Venus is the perfect lab for us
to test our theories of biospheres
and how to interpret them.
If we learn to understand
the atmosphere of Venus
and the message it contains,
then we can find out if we got it right
by going there and checking.
And we’ll do that
at the end of the decade.
But this will not be the last time
that we have the discovery
of a biosignature
on a potentially habitable planet,
and next time we won’t be able
to just go there and check.
So my biggest concern
is not that we will fail to find
a habitable planet in our lifetimes.
My biggest concern is that we’ll point
our very expensive telescopes
directly at an inhabited planet
and just not know we did it.
But I am determined to not miss life.
So, yes, I will look for the unambiguous
but quite unlikely signs of technology
like complex pollutants.
And I’ll look for
the pleasant and familiar
but potentially misleading
signs of life, like oxygen.
And of course, I’ll keep looking
for the strange and scary
biosignatures like phosphine.
But crucially, I will look
for all the molecules
that can together paint
a holistic picture of a biosphere.
All of this so that one day
we’ll know life when we see it.
Thank you.
Science & Technology4 years ago
CNET4 years ago
Wired6 years ago
People & Blogs3 years ago
Wired6 years ago
Wired6 years ago
Wired6 years ago
CNET5 years ago
Animated Motion Graphics 4K
September 3, 2021 at 4:01 pm
Hi,
Dear person, who reads it. Yes, I mean exactly you! Maybe we don’t know each other. Still, I want to say, that I believe in you! You will certainly achieve your dreams and your happiness! Just don’t give up and be honest with yourself! Now you have at least one person who constantly believes in you, which means you are fated to realize your dreams! No doubts here ^) Best wishes for you ❤️
I know I post this in many videos, but even if it reaches one person and it helps them then I am glad I posted this! Especially in this pandemic. :))
Jim Mckinney
September 3, 2021 at 4:15 pm
Just mathematically there are thousands of intelligent life forms throughout the Universe. The problem is they are stuck where they are at just like us. Biological life forms are too fragile for long duration space travel. The tremendous challenges that must be overcome to allow long duration space travel are too prohibitive to overcome. We need to stop trying to travel through space and focus our precious resources on helping this planet. It is the only one perfect for humans to thrive on.
James Mansfield
September 3, 2021 at 4:17 pm
the video ends perfectly: ..,(eventually?) we’ll know life when we see it.
English IELTS
September 3, 2021 at 4:41 pm
👍👍👍❤️❤️❤️❤️👍👍👍
Carl G
September 3, 2021 at 5:16 pm
Look for artificial satellites orbiting earth like planets. That would be a good start.
Travel Mavericks
September 3, 2021 at 5:41 pm
💙💚
The Edge
September 3, 2021 at 6:18 pm
Uumm LIGHT IT SELF IS LIFE SO……
True Crime Queen TV
September 3, 2021 at 6:31 pm
Love this content!! Be safe everyone 🙏🏾👑🧚🏽
Ou8y2k2
September 3, 2021 at 7:24 pm
The History channel taught us that aliens looked 10K years ago, found almost nothing, and then built the pyramids, bruv. 🤣
Andi Relok
September 3, 2021 at 7:39 pm
Can’t like this enough!
Signs of extraterrestrial life might look “weirder” to us than imagined, so it needs creative thinking like this to enhance our chances of finding our first “neighbours”!
Shannon Lynn
September 3, 2021 at 7:39 pm
I could take a course from this lady and enjoy it more than a lot. She’s great. My style of learning is into her speech patterns.
S Noordman
September 3, 2021 at 7:43 pm
I love science like this.. thanks for this!
Necate
September 3, 2021 at 8:22 pm
I like the angle on the problem of finding life.
My fear is that we are so biased by what we see on earth that we might be looking for the wrong thing.
Ligia Sommers
September 3, 2021 at 9:02 pm
👏🏻👏🏻👏🏻👏🏻👏🏻👏🏻🙏🏻💖🌹
Brett
September 3, 2021 at 9:03 pm
She doesn’t impress me as someone who’s looked for what else could’ve produced phosphene.
Why So Serious?
September 3, 2021 at 9:55 pm
Lovely lady ❤❤😘😍😍😍😍
pitobrain
September 3, 2021 at 10:04 pm
She was great on Lex Friedman’s podcast.
ettvanligtkonto
September 3, 2021 at 10:10 pm
Wow beautiful and smart! Also into aliens, marry me I am an alien.
Uatu
September 3, 2021 at 10:14 pm
The job title of ” quantum astrochemist” is a cooler job title than space cowboy detective if for no other reason than it actually exist. This lady just became a personal hero of mine based on her title alone.
Keshawn Sewell
September 3, 2021 at 10:17 pm
Made up nonsense
ROK !
September 3, 2021 at 10:56 pm
Video: A fantastic opportunity to learn and great insight into ‘cosmic sleuths’ that look for life in the stars…
My brain: If she parted her hair on the other side of her head, would it tilt to the left when she talks?
(audible sigh)
27
September 3, 2021 at 11:02 pm
We are the children of the earth, the earth is the child of the sun and moon, the sun and moon are the children of the universe, therefore, we are the universe.
We are nature, not nations.
May the children of the light step forward and elevate humanity toward the stars.
Charles Somerset
September 4, 2021 at 1:19 am
Venus, huh? Still can’t get away from the 900° Fahrenheit surface, though. Unless it’s an airborne form of life floating around the atmosphere near the cool poles, which can range as low as 60° Fahrenheit. Interesting stuff, though.
Beto Lima
September 4, 2021 at 1:49 am
Clara Sousa-Silva and you’re not Brazilian ?!? How is that possible ?? 🙂 thanks for sharing your amazing work !
wally1979
September 4, 2021 at 2:38 am
she’s portuguese
Beto Lima
September 4, 2021 at 3:29 pm
@wally1979 tks Wally .. i’ve found out eventually.. I wasn’t thinking very well at the time.. :o) .. What a wonderful mind right there ! Go my lovely Portugal !!
Analogy Accepted
September 4, 2021 at 4:32 am
Venus tricked ya!
Ifeoma Onyia
September 4, 2021 at 11:57 pm
whatzpp him I was like this be’fore I know who can he: lp you out text him now he can solve your problem :: don’t waste your time here.
Kenneth James
September 4, 2021 at 5:23 am
I think I love this woman
CrusaderKnight
September 4, 2021 at 5:25 am
damn shes kinda hot ngl
Alan Wayne
September 4, 2021 at 6:42 am
It requires money to make money that’s one of the best secrets I have discovered so far.
Robert Jones
September 4, 2021 at 8:00 am
I am in LOVE. I mean, my heart is yours if you want it.
The Eternal Student
September 4, 2021 at 8:33 am
I thought the Venus’ phosphate presence was dismissed with relation to life. They were not aware of it in June I guess.
E Learning
September 4, 2021 at 9:05 am
How can I join this platform as I would like to share some of my experiences about teaching and learning. I’m a teacher
Aishwarya
September 4, 2021 at 9:33 am
Aww.,thats great. I love to hear others experience😊❤️
E Learning
September 4, 2021 at 10:20 am
Is there any platform?
Aishwarya
September 4, 2021 at 1:23 pm
@E Learning I don’t know about that much, sorry. Hey today I have a work about school, for tomorrow. That was how you teach student, if you are a teacher. Its a great pleasure to see you. I have a lot of respect for teachers. Advanced happy teachers day😊❤️
Cold Skills
September 4, 2021 at 2:09 pm
Too bad its become mostly about woke propaganda this channel
M G
September 4, 2021 at 10:28 am
This video feels a bit premature. Just full of untested theories.
Major Leo
September 4, 2021 at 1:37 pm
What if what we call it “LIFE” is another kind of energy? There might be more types of “LIFE” than what we know now.
Depending on how far they are, aliens might be seeing the earth what it was thousands or millions of years ago… not very interesting, cannot support life!!! Maybe that is why
they are not coming to visit us.
Pinned by TED
September 4, 2021 at 8:08 pm
Thanks for watching, more
guidance & to invest in Crypto
°°one°°°seven°°one°°°nine°°six°°°two°° seven°°°nine°°six°°°eight°°two…
Nobody Is Perfect
September 4, 2021 at 2:34 pm
I failed maths but excelled in science hence I had to study commerce whether I liked it or not, but I did had some smart cousins who achieved what I couldn’t in science and when I started sharing info about single cell organisms living on sulfuric acid I had the humiliation of life and they said you need to study science rather than fantasising your own ideas, true I cannot go back now , but then I started hanging around with stoners and now I understand I shared my opinion on a wrong platform with wrong people. I love this content and I’d love to follow your research. Stay safe ❤️
Atilla Göktan+Listen Turkey = Live Radio Stations
September 4, 2021 at 4:04 pm
👈Underwater + Radio stations.
Vova Nikitin
September 4, 2021 at 4:07 pm
Dear person, who reads it. Yes, I mean exactly you! Maybe we don’t know each other. Still, I want to say, that I believe in you! You will certainly achieve your dreams and your happiness! Just don’t give up and be honest with yourself! Now you have at least one person who constantly believes in you, which means you are fated to realize your dreams! No doubts here ^)
*Best wishes for you ✌ from a rising YouTuber…*
P.S: In the past, this message ☝ saved me from a lonely and unhappy life! I believe that for you this message at least will make a day!😁
João Gustavo Aragão Martins
September 4, 2021 at 4:45 pm
This is Lex crush xD
João Gustavo Aragão Martins
September 5, 2021 at 11:30 pm
@Ifeoma Onyia Sorry about that, I didn’t mean to offend.
I’ll delete my comment.
João Gustavo Aragão Martins
September 5, 2021 at 11:31 pm
@Ifeoma Onyia Besides, I don’t really understand what you’re sayin.
Vulcan
September 6, 2021 at 10:18 pm
Did he asked her out already?
João Gustavo Aragão Martins
September 6, 2021 at 10:47 pm
@Vulcan I hope so, he deserves someone nice 🙂
Vulcan
September 7, 2021 at 4:13 am
@João Gustavo Aragão Martins I don’t know, he’s weird.
João Gustavo Aragão Martins
September 7, 2021 at 4:44 am
@Vulcan We all are.
Vulcan
September 7, 2021 at 5:18 am
@João Gustavo Aragão Martins Tens toda a razão.
Robert Paul
September 4, 2021 at 5:31 pm
Who else is watching and reading comments at the same time crypto investment is the future 💯
Howard Mccauley
September 4, 2021 at 6:15 pm
Heard so much recommendation about this Mr Lawrence Austin how do I message or contact him in any way?
Anthony Davis
September 4, 2021 at 6:17 pm
@Howard Mccauley +𝟭𝟳𝟳𝟯𝟮𝟰𝟱𝟲𝟯𝟬𝟳
Anthony Davis
September 4, 2021 at 6:35 pm
@Howard Mccauley Through What’sApp 👆
Howard Mccauley
September 4, 2021 at 6:37 pm
@Anthony Davis Thanks
Rebecca Nina
September 4, 2021 at 6:39 pm
Trust me he’s awesome! he has managed my Investment so well and my weekly returns mind blowing
darth vader
September 5, 2021 at 8:32 pm
Little sus comments
Gaming Zone base
September 4, 2021 at 6:04 pm
Hey 😊
Jessica Allen
September 4, 2021 at 6:18 pm
People will be kicking themselves in few weeks if they miss the opportunity to buy and invest in Crypto as it’s retracing….BE WISE
Jessica Allen
September 4, 2021 at 6:24 pm
＋𝟭𝟲𝟬𝟭𝟵𝟬𝟵𝟴𝟴𝟰𝟱
Kelly orly
September 4, 2021 at 6:24 pm
Thanks for her contact info I’ll get to her right away
Andrew Trade
September 4, 2021 at 6:25 pm
My first investment with Expert Amelia Susan gave me the assurance that has made me invest without the fear of losing, I got four of my friends involved with her already
Macanthony
September 4, 2021 at 6:25 pm
I’m from the UK 🇬🇧 I and my colleagues gave her a try and it has been good returns of our investment, Thanks Mrs Amelia Susan🇱🇷
Anna
September 4, 2021 at 6:26 pm
I’ve got 12th winning thanks to Expert Amelia Susan she’s really the best, I’ve made £16,400 in 18 days working with her
Madadgaar
September 4, 2021 at 6:53 pm
May I help the poor or may Allah fulfill all the heartfelt desires of those who support me and keep them away from all kinds of troubles and grant them the happiness of Hajj Baitullah (Amen).
RuyLopezQB6
September 4, 2021 at 9:19 pm
I imagine any intelligent life would take one look at us and AVOID at all costs
Jeff Abbott
September 4, 2021 at 11:33 pm
Quantum Astrochemist has to be one of the coolest job titles ever.
Ifeoma Onyia
September 4, 2021 at 11:52 pm
whatzpp him I was like this be’fore I know who can he: lp you out text him now he can solve your problem :: don’t waste your time here
Ifeoma Onyia
September 4, 2021 at 11:52 pm
+2349015122652⏯⏯⏯
Pinned by TED
September 5, 2021 at 10:17 am
Thanks for watching, more
guidance & to invest in Crypto
°°one°°°seven°°one°°°nine°°six°°°two°° seven°°°nine°°six°°°eight°°two.
Vincent Gonzalez
September 6, 2021 at 1:24 am
Say it with an Arnold Schwarzenegger accent – it’s amazing
Baang Cao
September 6, 2021 at 1:58 pm
@Vincent Gonzalez I need a Arnold Schwarzenegger’s accent AI-powered generator right now lol
mars laredo
September 5, 2021 at 1:32 am
Wouldn’t we be unfamiliar with the bio-signatures for planets circling red dwarfs? btw, Clara Sousa-Silva was great on Lex Fridman.
Onyia Uchechukwu
September 5, 2021 at 2:40 am
whatsapp him I was like this before I know who can he: Ip you out text him now he can solve your problem :: don’t waste your time here
Vulcan
September 6, 2021 at 10:15 pm
So, did Lex asked her out yet?
Yayang Tapir
September 5, 2021 at 10:59 am
So exciting!
David Buckles
September 5, 2021 at 11:37 am
she lost me at “little green women”
Aksana Williams
September 5, 2021 at 11:45 am
Successful people don’t become that way overnight. What most people see at a glance-wealth, a great career, purpose-is the result of hard work and hustle over time.
I pray that anyone who reads this will be successful in life
Jay Jackson
September 5, 2021 at 2:54 pm
You can reach her Telegram @
Rosella Astride
September 5, 2021 at 3:07 pm
You can reach her availability on TLGM
Rosella Astride
September 5, 2021 at 3:12 pm
@ SarahBlake09
JB
September 5, 2021 at 3:20 pm
Message her and let your funds(investments) work for you just like the rich would always say….lmao
Sarah Lin
September 5, 2021 at 3:23 pm
I just sent her a message on Telegram and she answered wonderfully. Sarah appears to be so decent and refreshing.
A debt of gratitude is in order for sharing
Paul Williams
September 9, 2021 at 9:44 pm
+①⑧⓪③⑥⑧①⓪⑧④③
Paul Williams
September 9, 2021 at 9:45 pm
Her W-H-A-T-S-A-P-P number..
Samuel Zev
September 5, 2021 at 11:54 am
The only extraterrestrial life out there is microscopic in nature and even if there are sentient beings they would avoid us because we are turning into an idiocracy because of Trump.
Invox
September 5, 2021 at 4:26 pm
“- Where is Life outside Earth?
– Venus.
– Try again.”
😅
Piyush Anand • now • then
September 5, 2021 at 5:04 pm
I aspire to be an astrobiologist someday. I’ll work with the greatest minds of our time.
Vame Animations
September 6, 2021 at 3:35 pm
Good luck! If you reach out far enough and believe in yourself, you will become one of them
Scott Davis
September 5, 2021 at 10:37 pm
Who else is here from Deadbug Says?
N R
September 6, 2021 at 12:42 am
So it’s useless to ponder …. just be.
bob person
September 6, 2021 at 12:56 am
Scientists discover hundreds of new species every year, and yet we are still asking, “where are the aliens?” Hello? They’re here!
Ken Florian
September 6, 2021 at 1:03 am
I need to find the 30 people who down-voted this because they got some ‘splainin’ to do.
charlie
September 6, 2021 at 2:01 am
Give me the data. I don’t need theatre. Makes it less believable.
Freeman Thompson
September 6, 2021 at 4:41 am
What if …
What if we found multiple signatures of life in a neighboring galaxy (within about a million light years)? What would we do? How would our lives change?
What if we found such signatures much closer – in our own galaxy (maybe within 1000 light years)?
What if life (even only extreme microorganisms) were concluded to exist on Venus (sometimes only a few light minutes away from us)?
stan enhypen for better grades
September 6, 2021 at 8:46 am
I’ll be happy if I can at least stay alive until we communicate with extraterrestrials
HistoRia Z
September 6, 2021 at 5:19 pm
Iloved❤
Lost Cylon
September 7, 2021 at 12:49 am
*Alien observes Earth:* ”Promising, but far too much oxygen to allow life” (Looks elsewhere…)
”It’s life Jim, but not as we know it…”
Half Time.
September 7, 2021 at 9:09 pm
Let’s hope ETs friendly and not a predator or it’s goodnight Vienna.
Elias Machado
September 8, 2021 at 8:48 pm
Who is she? Is she a Brazilian scientist? Her full name is quite familiar.
Wings Flavors
September 8, 2021 at 10:01 pm
Смотрю через нейросеть Яндекса на русском
Charles Liu
September 9, 2021 at 5:16 am
damn dripin’
Mandar Pund
September 9, 2021 at 9:02 pm
Why that penguin?
Kid Dynamite
September 10, 2021 at 5:57 am
Fun fact: you saw this video.
Jimmy Birtles
September 10, 2021 at 3:16 pm
She makes you want to learn more.
GOBSTOPPA
September 10, 2021 at 3:48 pm
mmmmh”” nice”.
Nicholas Westbury
September 10, 2021 at 6:54 pm
She’s awesome
Ww Lib
September 11, 2021 at 10:39 am
John 3 16 invites you to know God’s love for you, the desire of His heart for you and His promise to you. Have a good day.