Neil deGrasse Tyson on Gravity and Carbon-Based Life

What is the impact of gravity on the development of carbon-based life? What would happen to life forms on Earth if we had twice our normal gravity? Neil deGrasse Tyson answers a fan's Cosmic Query, with comic co-host Chuck Nice.

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[StarTalk]

*Today's "Side Order of Science":*

[StarTalk]

New Video: Neil deGrasse Tyson explains the impact of gravity on the development of carbon-based life on Earth in this Cosmic Query with Chuck Nice:
Neil deGrasse Tyson on Gravity and Carbon-Based Life

[PrabinPebams]

I was waiting to hear about the upper limit of how big a planet can be before it stops supporting carbon based life assuming every other criteria for life support is met. That was not addressed. :(

[SNEAKYSNAKEX]

We love you Niel and Chuck! Keep the hits coming! It's always a pleasure to listen to you guys! Sorry about all of the exclamations.

[tremalow]

Life would change, especially in the ocean. The water column has a very distinct temperature and oxygen column. Swimming at half depth changes the temperature and oxygen content of the water. There is a "keystone"experiment with  barnacles. Three species living withing a few feet of each other dont survive when transplanted.
Would gravity effect how tall a plant would grow? Idk, but I imagine that if there were still tall trees, there would be an animal that adapted to eat what others couldnt grab, i.e. giraffe

[MarcErlich]

I agree. This channel is the best. Neil- please post larger video files daily!

[PokGuy]

great answer - at the end of the video fish = fishes?

[josmargarcia]

this is exactly why i want to become a physicist when i grow up. all of that knowledge!!!

[GarySarverShow]

That was so awesome!!!! and thanks

[Jwinius]

Regarding the swimming depths of fish, I believe they inhabit their favored depths not so much because of the pressure, but due to the available light and/or oxygen.

[ToyokaX]

J Winius False; a deep-sea fish will die after a while from lack of pressure if brought near to the surface since their bodies are accustomed to a certain depth.

[pratherat]

I love to listen to that brilliant man speak.

[Stannnnnnnnn]

Warrant Officer 1 (WO-1) An officer appointed by the Secretary of the Army. They are addressed as 'Mr' or 'Ms'
WO1s are basic level, technically and tactically focused officers who perform the primary duties of technical leader, trainer, operator, manager, maintainer, sustainer, and advisor.
They are not saluted by lower ranks.
WOs are in between the NCO Non Commissioned Officers (Cpl through Command Sgt Maj CSM) and the COs (2nd Lt to GOA, a 5-star Gen. of the Army)

[aoeu]

The most gravity you can have on a terrestial planet is 50% higher gravity than Earth, because as the mass of a planet increases, the radius and thus distance from the center of gravity increases, and its density decreases since more gravity means light elements won't fly away when heated by the sun. Saturn, Uranus, and Neptune all have the same gravity as Earth despite having more than 10-40x the mass.

Jupiter has 2.5x the gravity, but its massive atmosphere has caused enough heat and pressure to melt the silicate surface so its a smooth compressed fluid all the way down until the core.

In a super Earth with 1.5x the gravity, every animal would be wider and less tall, a giraffe can exist, but its only in terms of being relatively tall. Not only would all the animals be less tall, but mountains would be less tall, their eyes would be wider too, so relatively from the point of view of the wider creatures, they might not think they are wide. A superearth giraffe wouldn't be as tall as an Earth giraffe, but to a superearth person a superearth giraffe is just as tall as a giraffe is to us.

[Leon]

So is Tyson basically saying if the earth was double the size (double gravity), everything would still have evolved like it has, like humans, giraffes, elephants, etc but just shorter?

[rtyuik]

i dunno about this answer...it kinda sounded like a "take Present-Earth, and double its gravity, overnight" kind of answer, when i think the question was looking for more of a "what if Earth ALWAYS had double-gravity?" answer...so i think that most of the animals that we know today would have adapted and evolved similarly, just adjusted to a heavier weight...like, muscle mass might increase slightly, but the skeletal structure would be denser...giraffes would probly evolve to still be the same height, but their blood vessels would adapt to having higher-pressure bloodflow...the fish in the ocean would probly adapt to still fit their 'usual' biomes...if Earth had ALWAYS had a gravitational pull of 19.6m/s^2, then that would be the 'new' Unit of Gravity...we (on this "2xEarth") would look at 'normal-Earth' gravity and think that a MoonJump cheat was turned on, like in a videogame, because life would be 'used to' the constant 2G's of force...

[bartonpaullevenson]

There is probably an upper limit to how large a planet can be before it turns into a gas-giant; following Weiss and Marcy it would be about 4.8 Earth masses. I think corresponding gravity would be somewhere around 2 or 3 g.

[Abdikarimelmi]

Complex organism like Snake and other similar shaped animals like worms would actually thrive in an 2g environment. 

[JacobHayden]

They didn't say "Thank got your service." to the soldier! Oh well. Probably forgot.

[Cushy]

Did anyone hear about the new earth like plant discovered called kelper-10c its 2x teh width of earth ?