Where Are All the Exo-Earths?

Scientists have discovered over 5,000 exoplanets in the last few decades, but where are the Exo-Earths?

Hosted By: Savannah Gearry
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[NewMessage]

"The wobble method" is how I get my keys in the door at around 3 AM.

[leepemberton]

Just think of all the intelligent species out there looking up into their skies and wondering if they're alone.

[samwill]

Space is so impossibly large that there could be 50 billion planets functionally identical to earth just based on statistics that we either haven't found a way to see or just haven't gotten around to looking at yet.

[Wild_Bill]

It’s like the joke about the cop who sees a guy searching for his car keys under a street light in the park. Cop asks, are you sure you lost your keys here? Guy says, oh no, I lost them over there but there’s no light over there and I can’t see anything over there.

[jimrodarmel]

Another concern with the methods listed is they are less effective the more the target system's ecliptic plane differs from our own. Doppler shifts are less pronounced the less edge on the observed orbit is. If the planet's orbit never crosses in front of the star from the observer's POV, it's invisible. The planet and star may not be distinguishable depending on how the system passes through the gravitational lens.

[Freddie_Dunning-Kruger_Jr.]

8 planets‽
8‽
The day I don't recognize Pluto as a planet is when you pry it from my cold, dead hands!!

[mozismobile]

Our setup is like the drunk looking for his car keys under a street light... we're only looking in the places it's easy to look. And just hoping that what makes them easy to see doesn't affect how likely they are to have planets. It's all we *can* do, but that doesn't make it ideal.

[TimeTheory]

Three decades ago, we had nine planets. Ah, the good old days

[irlshrek]

Man, imagine what the James Webb space telescope would be able to see it was at the right place and time for a gravitationally lensed galaxy!

[kirknorman]

Excellent educational production, thank you!

[Matatabi]

Never watched a savannah Gearry video before good job you’re a great host !

[osmia]

Great graphics explaining the gravitational attractions of both star and planet. Made it super clear to me how that works

[little_forest]

WRONG! 30 years ago we did not just know about 8 planets in our solar system, but about 9! :)

[yodorob]

I'm sure that those exoplanets (and exomoons) that haven't been found yet will yield lots of surprises we couldn't even imagine right now.

[underworldguy]

So informative. Thank you for not keeping human biases. That can keep us from finding what is actually there. Thank you.

[dreamydoc]

This video is concise and informative 👌

[payamkohan]

Wow, you are good. Didn't expect this from a new member 😍

[bleep]

I love the thumbnail, made me chuckle

[j]

Great video and explanation. Thanks from England.

[Bekindallways]

Love the host! Hi savanna, hope to see you more.