figl4567 t1_ixjh41q wrote on November 23, 2022 at 10:10 PM

I think this is how the earth got its water. Huge chunks of space ice hit earth and melted. If we got hit with one and it doesn't kill us right away I'm curious about what the earth would look like. Land masses would change if sea water rises 40 feet

s1ngular1ty2 t1_ixjkwkz wrote on November 23, 2022 at 10:38 PM

If a large chunk of ice like a COMET hit Earth it would literally wipe out all life on the Earth.

Something like this...

https://www.youtube.com/watch?v=VNtsVP42bOE

Followed by a nuclear winter that never ends where all life dies due to lack of sunlight.

Strange-Ad1209 t1_ixjnl85 wrote on November 23, 2022 at 10:58 PM

Well most water came from Asteroids since the ratio for standard hydrogen versus heavy hydrogen in Asteroids matches the ratio in Earth's Water cycle. Comets have a much greater ratio of heavy hydrogen than standard hydrogen so water from comets isn't the source for water in Earth's Oceans/Lakes/Ground Water/Clouds.

s1ngular1ty2 t1_ixjo1r9 wrote on November 23, 2022 at 11:01 PM

Yeah and when they landed they probably killed anything in close proximity and also probably altered global temperatures. Do you think that a massive ice rock is any different from a normal rock when traveling at thousands of miles per hour? It goes through the atmosphere in a couple of seconds. It can't melt fast enough. It is just like a normal rock hitting the Earth.

Strange-Ad1209 t1_ixjqi8i wrote on November 23, 2022 at 11:20 PM

And all of the impacts that brought water were while the Earth was molten rock anyway. Except for the late term bombardment which heavily cratered the Moon and of course the Earth equally so, most impacts occurred in the first Billion years of Earth's 4 Billion year existence. Life didn't even appear until 2 Billion years ago and that was single cell stuff. Great Permian Mass extinction was 240 Million years ago. Dinosaurs 65 Million years ago. Many Mega Fauna 50,000 years ago from a string of Asteroid strikes like one here in Arizona near Winslow. Then the Usselo Horizon 26,000 years ago largely world wide forest fires from meteor strikes leaving layers of charcoal world wide. Asteroid winters usually only last about 1000 to 2000 years before clearing.

s1ngular1ty2 t1_ixjqpn0 wrote on November 23, 2022 at 11:22 PM

Incorrect. Stop trying to tell me things you don't even understand. Life existed almost immediately after the Earth formed. New evidence puts primordial life back to almost the very beginning of the Earth's existence. You should do some more research on the topic.

live_2_know t1_ixl8qdg wrote on November 24, 2022 at 7:36 AM

Agreed. Single cell life evolved around 4-3.5 billion years ago when the early earth's atmosphere was devoid of appreciable levels of oxygen. Many of these early life forms died out in the first mass extinction brought on by the evolution of cyanobacteria and the subsequent great oxygenation event of our planet about 2.5 billion years ago. It is always fascinating to remember that the introduction of such a reactive element (oxygen) to our planet in the form of O2 resulted in evolutionary opportunities for energy capture in biological systems by oxidation of food (sugars, amino acids, fats) to generate ATP and GTP. Processes that we humans carry out with respiration. Increased available oxygen dissolved in world oceans and in the atmosphere also lead to an extensive diversification in the minerals present on earth. So the rise of oxygen producing life forms actually terraformed earth to the conditions we see as 'normal' today. We live by exploiting oxidation in a world crafted by oxygen generating life. You can still see cyanobacterial stromatolites in Shark Bay, Australia and imagine a similar scene 2 billion years ago.