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All life on Earth is illegal immigrants from another planet.
This could mean in the Drake equation ne -number of planets capable of life- is very small. A planet has to be hit with a comet big enough to deliver a large amount of water but not so big or fast to destroy it. And be in the Goldilocks zone of the star. Also the mass of the planet would play a part - gravity of more massive ones would be more likely to capture a comet. But again, too massive and I could see that hampering life.
How does this square with the fact that we have solid evidence of water on Mars as well?
Imagine this sci-fi plot twist:

Aliens make live habitable by hitting proto-Earth with a planet, so life can sprout there.

They calibrated it such a way that angular size of Moon is the same as of Sun.

So we're not only made of elements which formed inside star(s) but also ones merged from two different planets. This is weird.
Is this the same collision theorized to have created the moon?
Absolute garbage.

The Earth has a nearly perfect circular orbit. Any collision with another planet would have pushed it off its orbit and caused it to at the very least created a more elliptical orbit that likely would have made the swings in temperature more deadly for life on Earth.

This entire article is science fiction.

Related, a recent study suggests up to 1% of our mantle is water trapped within rock that gets released as subduction increases to higher heat and pressure. This water could account for three times the amount of water on the surface and may represent a whole-Earth water cycle.

https://www.bnl.gov/newsroom/news.php?a=111648

I wonder how this ties in with the submitted link about Theia. And it will be interesting if we ever get similar trapped water discovered in martian rock.

The article says the light elements hydrogen, carbon and sulfur (and oxygen?) were only able to condense on the outer planets (and their moons). And the original article specifically says "the inner Solar System planets Venus and Mercury are largely devoid of volatile elements". If that's the case, why does Venus have so much carbon dioxide?

(I'm not saying the article is wrong, just trying to understand.)

I've tried reading the paper, which is obviously less hand wavy than this mess of a blog post but pretty tough going for a layman. I still don't see how they conclude that the water arrived all at once instead of in a bunch of comets... https://www.science.org/doi/10.1126/sciadv.adw1280
Not buying it, Mars had water with no major collision.
Claude Sonnet 4.5 summary of the original paper [https://www.science.org/doi/10.1126/sciadv.adw1280] for middle school students:

How Earth Got Its Water: A Cosmic Detective Story

The Big Question: How did Earth become a planet with oceans and life, when it formed so close to the hot Sun?

What Scientists Did:

- They used a "radioactive clock" made from two elements: manganese and chromium - Manganese-53 breaks down into chromium-53 over time (like ice melting at a steady rate) - By measuring these elements in meteorites and Earth rocks, they figured out WHEN Earth's basic chemistry was locked in

Key Finding: Earth's chemical recipe was set within just 3 million years after the Solar System formed (that's super fast in space terms!)

The Problem: At that point, early Earth was missing the ingredients for life—especially water, carbon, and other "volatile elements" (stuff that evaporates easily when hot)

Why Earth Was Dry: Close to the Sun, it was too hot for water and other volatile stuff to stick to the rocks that built Earth—they stayed as gas and floated away

The Solution: About 70 million years later, another planet called Theia (which formed farther from the Sun where it was cooler) crashed into Earth:

This collision created our Moon It also delivered water and other life-essential ingredients to Earth

The Big Takeaway: Earth needed a cosmic accident to become livable. Without that lucky collision bringing water from the outer Solar System, we wouldn't be here!

Why This Matters: If Earth needed such specific, lucky events to support life, habitable planets like ours might be much rarer in the universe than we thought.

(comment deleted)
What I don’t understand is how you define a single point (even if the point spans a million years) of “when the solar system formed.” They say the chemical composition of the Earth solidified “only 3 million years after the solar system formed” — isn’t the formation of the planets itself part of the formation of the solar system? How does one define the moment of formation? Or does this mean that we know with certainty that there was no physically consistent body one could identify as “Earth” 3 million years prior, and then within those 3 million years, it coalesced and solidified?
I wonder how much adenine, guanine, thymine, and cytosine was present in that water.
I don't understand why all these volatiles (hydrogen, nitrogen) didn't evaporate during such huge collision, which likely melt the whole Earth's crust. Even if a temporary atmosphere was formed, with high post-impact temperatures this atmosphere can't stay long.
>was rich in volatile elements essential for life, such as hydrogen, carbon and sulphur.

Today years old on learning that 'carbon' is a 'volatile element'. (I come to learn that astrogeology has a unique definition of volatile).

• The summary's own source article points makes no reference to carbon being volatile.

• The wikipedia article for 'volatiles' in the astrogeological sense makes no reference to carbon being volatile https://en.wikipedia.org/wiki/Volatile_(astrogeology) . Similarly, the wikipedia article for 'refractory', posed as the astrogeological opposite of volatile, does not place carbon at all in the spectrum of volatile to refractory.

• Contra: at least two papers do refer to carbon being a volatile element. https://www.nature.com/articles/s41586-022-05276-x and https://arxiv.org/abs/2311.18262

[shrug]

Tough to gain any predictive information here due to the anthropic principle requiring a series of comical happenstance for observation to even occur.
From a purely mathematical, scientific, and logical standpoint, I must regard this article as entirely speculative. The scientific claims it presents are extraordinarily improbable, and sound reasoning compels their complete dismissal.
I thought the consensus was that the water came from comet impacts?