Would the evolution of intelligent life
on Earth have been possible without the
moon? I find contradictory statements
on the Internet. Most say that the moon
is needed to stabilize the Earth axis,
one Jason Barnes says that Jupiter alone
could do that.

On Thu, 10 Jun 2021 06:35:42 -0700 (PDT), Lothar Frings
<Lothar.Frings@gmx.de> wrote:

>Would the evolution of intelligent life
>on Earth have been possible without the
>moon? I find contradictory statements
>on the Internet. Most say that the moon
>is needed to stabilize the Earth axis,
>one Jason Barnes says that Jupiter alone
>could do that.

Venus has no moon. Is its axis unstable?

Are the moons of Mars large enough to have any effect on its axis? Is
its axis unstable?

Is intelligent life possible on Earth even with the moon?

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Il 10/06/2021 15:35, Lothar Frings ha scritto:
> Would the evolution of intelligent life
> on Earth have been possible without the
> moon? I find contradictory statements
> on the Internet. Most say that the moon
> is needed to stabilize the Earth axis,
> one Jason Barnes says that Jupiter alone
> could do that.

I think that life on Earth depends on millions of coincidences and
incredibly rare events.
One of them is the presence of the Moon with the right mass and the
right distance from Earth.
Without Moon there would not been life as we know it.

Luigi Caselli

On 6/10/2021 6:35 AM, Lothar Frings wrote:
> Would the evolution of intelligent life
> on Earth have been possible without the
> moon? I find contradictory statements
> on the Internet. Most say that the moon
> is needed to stabilize the Earth axis,
> one Jason Barnes says that Jupiter alone
> could do that.
>
Along with what Luigi says:

https://en.wikipedia.org/wiki/Rare_Earth_hypothesis

"Rare Earth hypothesis

The Rare Earth hypothesis argues that planets with complex life, like
Earth, are exceptionally rare
In planetary astronomy and astrobiology, the Rare Earth hypothesis
argues that the origin of life and the evolution of biological
complexity such as sexually reproducing, multicellular organisms on
Earth (and, subsequently, human intelligence) required an improbable
combination of astrophysical and geological events and circumstances.

According to the hypothesis, complex extraterrestrial life is an
improbable phenomenon and likely to be rare. The term "Rare Earth"
originates from Rare Earth: Why Complex Life Is Uncommon in the Universe
(2000), a book by Peter Ward, a geologist and paleontologist, and Donald
E. Brownlee, an astronomer and astrobiologist, both faculty members at
the University of Washington.

In the 1970s and 1980s, Carl Sagan and Frank Drake, among others, argued
that Earth is a typical rocky planet in a typical planetary system,
located in a non-exceptional region of a common barred-spiral galaxy.
From the principle of mediocrity (extended from the Copernican
principle), they argued that we are typical, and the universe teems with
complex life. However, Ward and Brownlee argue that planets, planetary
systems, and galactic regions that are as friendly to complex life as
the Earth, the Solar System, and our galactic region are rare."

It is an interesting and informative book.
It states the requirements for complex life include:

"1.1 The right location in the right kind of galaxy
1.2 Orbiting at the right distance from the right type of star
1.3 The right arrangement of planets
1.4 A continuously stable orbit
1.5 A terrestrial planet of the right size
1.6 With plate tectonics
1.7 A large moon
1.8 Atmosphere
1.9 One or more evolutionary triggers for complex life
1.10 The right time in evolution"

On 2021-06-10, Lothar Frings <Lothar.Frings@gmx.de> wrote:
> Would the evolution of intelligent life
> on Earth have been possible without the
> moon? I find contradictory statements
> on the Internet. Most say that the moon
> is needed to stabilize the Earth axis,
> one Jason Barnes says that Jupiter alone
> could do that.

It's unclear.

Our models aren't accurate enough to know with certainty some effects,
hence the different results between Barnes and Laskar's earlier results
from 1993 on whether the Moon does stabilize Earth's axis or not.

Moreover, we don't actually know the requirements for intelligence or
life in general to arise (beyond, at best, chemistry) so whether things
such as tides or moderate seasonal variations are essential is still a
matter of speculation.