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Astrophysicist and TED Fellow Sarah Rugheimer searches for aliens — but not the cartoony green kind. She’s looking for extraterrestrial microbes by studying how these single-celled organisms emit gases, which could reveal evidence of them throughout the cosmos. Wondering if we’re really alone in the universe, Rugheimer identifies two big hurdles to confirming life on another world and offers insight into what finding it might mean for us.
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[SHAPE YOUR FUTURE]
I want to find aliens.
Finding life on another planet
is not just going to be a little hard,
it’s going to be very hard.
But for the first time in human history,
we have a chance to detect
signs of life on another planet.
Or maybe we’ve already
detected it on Venus.
Or maybe not.
There are still two big hurdles
when it comes to confirming life
on another world.
The first is building a telescope
big enough to do this,
and the second is interpreting
what we will find.
When we think of extraterrestrial life,
we tend to think of aliens like
funny little green men,
not aliens as single-celled microbes.
But it’s actually detecting signs
of microbial life on another planet
that I’m most optimistic about,
and what I focus my research on.
I model how a star’s high-energy radiation
can make gases from microbes
harder or easier to see
with future telescopes.
Microbes have dominated our planet’s
biosphere for most of Earth’s history.
They’ve been emitting gases
that can be seen in our atmosphere —
even light years away —
for billions of years.
Now, if an alien astronomer
were looking at Earth,
they would probably detect gases
like oxygen, methane and nitrous oxide
before detecting signs of us.
Even with an active
biosphere like Earth’s,
most of the gases that indicate life
are coming from single-celled microbes,
not from animals.
This is what we’ll try to do
in the next decade of astronomy —
try to find signs of microbial life
on planets orbiting other stars.
But the technology to detect
the atmosphere
of a planet the size of Earth
around another sun
is incredibly difficult.
It’s like trying to determine the size
of a firefly in front of a spotlight
while looking from another continent.
What’s amazing is that
with telescopes in the 2020s,
we’re overcoming
this technological barrier.
The second issue defining alien life
will be to interpret what these
biosignature gases actually mean.
Twenty-one percent of our
atmosphere is oxygen,
and nearly all of that oxygen
comes from life.
So here’s the tricky question:
Would detecting oxygen
on another planet mean life?
No, not necessarily,
because we know of ways
to get oxygen without biology.
I try to understand a planet’s geology
and its star’s radiation
so that we can better identify
a true life signal.
And this is what makes the preliminary
detection on Venus of phosphine,
a potential biosignature gas,
so compelling but also so confusing.
Venus is not where
we expected to find life.
It is a hellish world,
with a surface temperature
of nearly 900 degrees Fahrenheit.
Could life be floating in the more
temperate upper atmosphere?
But then how would such life
eat and reproduce?
This discovery will have to be vetted
over the coming decade.
First, we must verify the detection
of phosphine itself,
and then later, we would have to confirm
that this gas is coming from life
and not from some unexpected
geological or photochemical process.
If true, this would be one of the most
profound discoveries of our generation.
If it turns out that we were fooled,
that we mistook this gas for biology
when it’s from some other process,
we will have a sobering lesson to apply
to planets orbiting distant stars.
Venus is close — literally,
our next-door neighbor —
and yet we still have trouble
understanding it.
The planets we’re finding
orbiting other stars
are weird and unexpected.
Some have the density of cotton candy,
and others rain molten iron.
And most stars are different from our sun,
with high-energy flares
that can make it difficult for life.
So the more we’re looking at
different biosignature gases,
the more we realize
that there’s no single gas
that’s enough to understand a planet
and to claim alien life.
It is just really difficult
to distinguish life from nonlife
from light years away.
And here’s where the ambiguity lies.
How will we know if a clue
is a sign of life or is not?
Well, first, we’ll need
to understand as much as we can
about a planet’s geology
and the star it orbits.
We’ll learn vital lessons
by exploring our own solar system
in places such as Venus and Mars.
We’re getting closer to answering
one of humanity’s biggest questions:
Are we alone in the universe?
Any claim will be hotly debated.
So basically, I’m stretched
between two desires.
I want to find alien life, but likely
will not have a clear answer.
And that’s OK; science is nuanced
and self-correcting.
It’s what I love about it.
Science is about balancing this duality
of skepticism and of hope.
We won’t be able to teleport
ourselves to another planet
and take pictures of alien
kangaroos jumping around.
And without an intelligent
“Hello, Earthlings!” signal,
we might still feel lonely,
even if we find out
we’re not alone in the universe.
Despite these challenges,
I’m super excited about alien microbes
and what they could teach us.
Even if we find just one
other sign of life,
then likely the universe
is teeming with it,
from single-celled to complex.
If we search for decades and find nothing,
then that is equally humbling.
But we must try.
We must do this search even when it means
sitting with uncertainty along the way.
Thank you.
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Smart Minute
June 22, 2021 at 3:28 pm
1:46 I really liked that explanation
trump the Trump
June 22, 2021 at 3:28 pm
I’m totally serious here, I misread the title as “searching for micropenis aliens” 😂😂😂
Laure Fesler
June 22, 2021 at 3:34 pm
Great video ! Also I was wondering (maybe this is stupid) do lifeforms emit (sound)waves in particular ? And if so could it be possible to search for life with sounds rather than images ?
zqlimy
June 22, 2021 at 4:03 pm
But that requires molecules which is pretty non existent above the upper atmosphere
Cas
June 22, 2021 at 5:43 pm
Sound doesn’t travel in vacuun
Laure Fesler
June 22, 2021 at 5:58 pm
@Cas aaah right thx
WK_fpv
June 22, 2021 at 3:35 pm
900 farenheit are about 482°C, you’re welcome.
Njul
June 22, 2021 at 3:51 pm
1:04 Ubuntu Linux spotted! <3
Michael Marshall
June 22, 2021 at 3:57 pm
I’m Sure there is Life on other Planets, just check out some of the people on this Planet, they seem to be from another World, 😆…
Celio Araujo
June 22, 2021 at 3:58 pm
Life: A “scale in”, emergent, non local, fenomenon… Planetary causes can’t explain ALL…
Roary
June 22, 2021 at 3:59 pm
did anyone else click on this thinking it was going to be an expose on Scientology
Rays Travel
June 22, 2021 at 4:22 pm
Not sure about micro. But when I was a firefighter when I was younger. I was trying to get some me time to sort some things out. So I went in my step dad’s back yard next to the Sandy river at the border of Sandy Oregon and brightwood Oregon. But I sat on a tree stump before I walked down the path to the river to do some fishing. When I sat down I looked up and I saw this sideways teardrop looking thing that was see threw. It was maybe 1 1/2 feet tall and maybe 3 1/2 to 4 feet long. It was maybe 15 feet off the ground. It was slowly circling me. Maybe for 30-40 seconds. I was so scared all I could think to say is I mean you no harm. I only saw it for less then a minute then it disappeared in thin air. This was the weirdest thing I’ve ever seen in my life and to this day I have no idea what it was.
Rays Travel
June 22, 2021 at 4:42 pm
@Ruby the light was bending around it. It looked like a solid object but just kinda see threw like on that movie the predator. Sounds silly comparing it to a movie but that’s the best I can think that would discribe how I could see it but also see threw it. It was there for about a half a minute then just vanished in thin air. It didn’t make any noise. I only noticed it when I looked up. Also I’ve seen swarm of flies and bugs before. 100% different. It’s nothing I’ve seen before.
Ruby
June 22, 2021 at 4:46 pm
@Rays Travel weird! Post this on the ufo subreddit they might be able to tell you what it could have been, probably a logical explanation but its fun to wonder
Rays Travel
June 22, 2021 at 4:59 pm
@Ruby I’ve always wondered what it was. Wondered if our government has technology they are not telling about or maybe even something off world. Huge place out in space. I’d think that circumstances like ours can happen elsewhere and create life. There are already planets with the same water type as ours so who knows. Maybe life is out there. Or here. Whenever I think about it I just think of it as a super weird experience that I’m not sure of. Not really sure what to think about it. Sometimes I think if it was a craft. Was there little people in it? or was it a probe?. But then again could just be our own technology.
Duffercity1
June 22, 2021 at 5:24 pm
Did you notice any mushrooms growing on and around the tree stump. ‘What wonderful trip it’s been’. js 😁😁😁😁😁😁
Rays Travel
June 22, 2021 at 5:55 pm
@Duffercity1 hahaha no it was summertime. Too hot for mushrooms 😂 but that’s funny. No swamps in the area as well, so no swamp gases or weird men wanting to give me an eye exam 😂
Herbert Heyduck
June 22, 2021 at 4:30 pm
It would be interesting to find not only the known biological life, but also other complex structures and their appearance of emergence. But it is a start.
André Magalhães
June 22, 2021 at 4:35 pm
TED needs a Dark theme for intro and outro! Because when i saw this at night my gawd, my eyes xD
Duffercity1
June 22, 2021 at 5:14 pm
So, are you also trying to verify that ‘Men are from Mars, and Women are from Venus’? Btw, interesting approach, and probably makes more sense than looking for “little green people/aliens”. Look forward to more discoveries using this unique approach to life on other planets, moons, or any other surfaces.
gsk
June 22, 2021 at 5:50 pm
cool ASMR for this type of subject
Abhishek De
June 22, 2021 at 6:06 pm
“Either we are alone in the Universe or we are not. Both are equally terrifying.” – Arthur C. Clarke
Jim Small
June 22, 2021 at 7:22 pm
Arthur C. Clarke did not, and would not, say this. He had an inventive scientific mind and would have delighted in finding evidence of either.
But to say the prospect would be “terrifying” is an insult to his memory.
To date there is absolute zero evidence of life anywhere except on earth. Like Arthur C. Clarke, I want there to be some evidence. Anything, including microbes. And there might be someday. But right now, there is none. Darn it.
Samuel Santos Silva
June 22, 2021 at 6:18 pm
It was interesting. But, the video was so short! Thanks !
MegaGrubby
June 22, 2021 at 6:52 pm
Wouldn’t a daily gas cycle point towards life? For instance, don’t oxygen and co2 cycle during the day based on life’s use of the suns energy then lack thereof? This tidbit seemed pretty shallow on content but I would like to see more on the topic.
Lala Eatin’ A Got Damn Burger
June 22, 2021 at 8:03 pm
Interesting
Sune Ricardo Holt
June 22, 2021 at 8:08 pm
Scientists using Fahrenheit 😱 sheize …
Expecting mostly American viewers 😛
JNLEEA L-A
June 22, 2021 at 8:33 pm
I Love you Sarah … MARRY ME!!!
BlondeGirlSez This
June 22, 2021 at 9:03 pm
UFOs are us from the future.
Jackie Grant
June 22, 2021 at 9:59 pm
Great explanation – thought provoking 🔬🧐👩🏾🚀🪐💫🌍🔭
Samuel Zev
June 23, 2021 at 12:24 am
No need to look at other planets for microscopic life, the ones here on earth are from these life forms brought to earth billions of years ago by comets, this is called panspermia
hacker x
June 23, 2021 at 12:35 am
It is an interesting thing to find aliens. You are so beautiful ,I like u LOL.
waddac2
June 23, 2021 at 12:37 am
Interesting…. the world has gone through a global pandemic with Covid-19 and many say it was human made……. Could Covid be Alien microbes from another planet wanting a different atmosphere etc?
Renégade
June 23, 2021 at 12:37 am
We are told we live on a spinning globe ran by little green men $$
Shrugs Haru
June 23, 2021 at 2:51 am
22 colonies of microscopic aliens that didn’t want to be found disliked this video
Mcburnie
June 23, 2021 at 10:54 am
lololo galactic federation..
Holofish
June 23, 2021 at 3:05 am
Wingardium leviosa!
Casey
June 23, 2021 at 4:13 am
y’all do all this but don’t call babies in women’s wombs “life”
Professor X
June 23, 2021 at 10:47 am
We call them life, of course.
Difference is that fetus doesn’t have developed self-consciousness, and it’s nutrition and development is dependant on the mother, so it can’t be equal to already born babies.
Ronero
June 23, 2021 at 6:00 pm
Any single cell is life.
Earthling-Z3R0
June 23, 2021 at 5:50 am
Nice editing skills right there 😀
Summer D
June 23, 2021 at 6:21 am
I wake up at 1 and get on youtube and this is suggested? Wow.
Jg235
June 23, 2021 at 10:37 am
The greatest researchers are always either chinese or people with german surnames.
Necate
June 23, 2021 at 11:14 am
the content is very interesting
the editing and sound design are … unnecessary to put it mildly
Jia was ana
June 23, 2021 at 11:21 am
6 pleidian appear in Alor island 1959!!!!,this is real not a joke!!!!!
Ach, Hallo Herr Nachbar
June 23, 2021 at 12:56 pm
de ehm teaaaa
Anuran Pal
June 23, 2021 at 1:07 pm
survivorship bias
2 GB Ram
June 23, 2021 at 1:56 pm
Lol! Alien doesn’t exist 😂 🤣.
President Oxford
June 23, 2021 at 1:59 pm
Life seeding molecules throughout the universe are like advertising junk mail spread by comets et all. A half maybe fertile landing spot and hey presto. A garden begins. I’m no scientist. It’s just common sense.
Maira Thorn
June 23, 2021 at 3:19 pm
*A good content after A LONG TIME!*
daued lex
June 23, 2021 at 6:57 pm
No thank you for finally someone using a scientific data approach to establishing a fact that we may not be alone I hope that your research money never runs out thank you
Leon Florence
June 24, 2021 at 5:58 am
I’m an alien. You found me.
Aniyans c
June 24, 2021 at 8:45 am
I ALSI EXPERIENCED ALIEN CONTACT..BUT NO ONE IS BELIEVING
Aniyans c
June 24, 2021 at 8:48 am
THERE CAME A UFO..AND TAKEN AWAY MY EVERYTHING
Unfiltered Voice
June 24, 2021 at 4:44 pm
Aliens are eating people. They cloak the person so that they become invisible and takes them. They eat human flesh. They roam the skies invisible.
M.A.Q Q
June 25, 2021 at 6:06 am
You chose Star Trek outfit aptly.
Yeah. We hope to discover life form, which could be celular and probably botanical. It will only flame our curiosity.
We have plenty of human related challenges on our plannet. I wish someone research on issues back home too.
Thaha Faris
June 26, 2021 at 11:56 am
Alien’s Mind Voice:
First,
Stop exploiting your planet,
Then you can discover our’s.
Read my ABOUT section PLEASE
June 26, 2021 at 9:49 pm
Ngl never heard of microscopic aliens until now…
nein und nein
June 27, 2021 at 7:27 am
You have a nice top. It’s something in the style of “Star Trek”, like in the season with captain Picard