the moons size coincidence?

Robbie Mayhem wrote:
"Weatherlawyer" wrote in message
oups.com...

garry parker wrote:
Do any moons of the other planets have the right size to produce a
similair
effect from that planets perspective?


Does the fact that it doesn't spin have anything to do with that?

If it could spin would it be able to support an atmosphere?


Ah, but the moon does spin. The period of its rotation is equal to its
orbital period, that is why the same side of the moon faces us.

And the coincidence in there escapes you?

(At the risk of starting -or whatever- a flame war) It severely limits
the time schedules for all the other chance factors that are required
for evil oceans to spawn, bear fruit not "of its kind" and go on to
conquer the planet in all its levels.

The odds of that happening are... on topic.

JRS: In article , dated
Sun, 2 Apr 2006 18:55:41 remote, seen in news:uk.sci.astronomy, Hayley
posted :
the amazing coincidence that the moon is exactly the right size to
exactly cover the sun about 6 times a decade to give us a spectacular
eclipse
seems almost to much to believe that it really is a coincidence,
but I cant think of anything in the evolution of the planets and the
creation of our moon
to suggest otherwise

Since the Moon's distance is steadily changing on a moderate
astronomical time-scale, there can be no astronomical reason for the
Moon being now a particular angular size.

On the other hand, therefore, the coincidence is that a more-or-less
intelligent race has evolved at the right time to see it. That's not
inevitably a complete coincidence.

If the Moon were visibly much larger, then the tides would make the
shore-line a permanent disaster area, which could prevent life moving
from sea to land. (If the Moon were much smaller, there would still be
the solar tides, which are of similar magnitude.)

If the Sun was of different absolute size, it would be of different
absolute brightness, and the zone where water is liquid would be at a
different distance. That would affect the solar tide, and so might have
significance.

All hypothetical.

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"Bill Kelly" wrote in message
...

"Hayley" wrote in message
...
the amazing coincidence that the moon is exactly the right size to
exactly cover the sun about 6 times a decade to give us a spectacular
eclipse
seems almost to much to believe that it really is a coincidence,
but I cant think of anything in the evolution of the planets and the
creation of our moon
to suggest otherwise

I think this goes along with the fact that the earth is in the ideal
spot in it's distance from the sun to produce the ideal tempurature, and
various other life preserving conditions. It is by God's design.
Yours,
Bill Kelly.


But there is no such thing as God?

On 3 Apr 2006 05:03:04 -0700, in uk.sci.astronomy , "Weatherlawyer"
wrote:


Robbie Mayhem wrote:

Ah, but the moon does spin. The period of its rotation is equal to its
orbital period, that is why the same side of the moon faces us.

And the coincidence in there escapes you?

In fact, the Earth's moon DOESNT quite keep the same face towards us.
Look up Libration and watch the limbs carefully.

But anyway its not coincidence, its a local minimum in the energy
configuration of two bodies. As the Moon rotates, its rocks are
deformed by the gravity of the earth. This absorbs energy. Eventually,
the energy loss caused the rotation to slow. Once the orbital speed
and rotational speed 'matched' the rocks stopped being distorted, no
more energy was lost, and a stable state was reached.

The same is happening to the Earth by the way, and to many other moons
in the solar system.
Mark McIntyre
--

"Mark McIntyre" wrote in message
...
On 3 Apr 2006 05:03:04 -0700, in uk.sci.astronomy , "Weatherlawyer"
wrote:

But anyway its not coincidence, its a local minimum in the energy
configuration of two bodies. As the Moon rotates, its rocks are
deformed by the gravity of the earth. This absorbs energy. Eventually,
the energy loss caused the rotation to slow. Once the orbital speed
and rotational speed 'matched' the rocks stopped being distorted, no
more energy was lost, and a stable state was reached.

The same is happening to the Earth by the way, and to many other moons
in the solar system.
Mark McIntyre
--

Yes.
Charon and Pluto are locked too; (no comments as to whether Pluto is a
planet please).
More to the point, ALL other known moons in the Solar System are
gravitationally locked to the parent planet, except Phoebe.
In addition:
Mercury is locked to the Sun, actually a 3:2 spin-orbit resonance which
accounts for it's large libration.
And Venus is locked to the Earth so that at closest approach it always has
the same side facing us. Not only is the orbit (year) of Venus in a 5:8
resonance with the Earth year, but its rotation (day) is in a 3:2 resonance
with the Earth year.

All this talk of coincidence and divine design is pure codswallop, taking no
account of natural mechanics. All the orbital distances and periods are
related geometrically for the same reason that a pendulum swings in simple
harmonic motion.

On Mon, 3 Apr 2006 18:07:28 +0100, in uk.sci.astronomy , "John
Brockbank" wrote:
It occurred to me long ago that the Moon's existence might well keep the
Earth more stable than it otherwise would be.

Its more likely to be the other way round - the tidal stresses on the
earth are quite large and could quite possibly contribute to
geological instability.

Mark McIntyre
--

Stephen Tonkin wrote in
:

"Hayley" wrote in message
...
the amazing coincidence that the moon is exactly the right size to
exactly cover the sun about 6 times a decade to give us a spectacular
eclipse
seems almost to much to believe that it really is a coincidence,

It is a coincidence, and one that we are fortunate enough to be able to
experience. As the Moon gradually moves further away, the frequency of
annular eclipses will gradually increase until, at some distant date,
totality will no longer be possible.

Bill Kelly wrote:
I think this goes along with the fact that the earth is in the ideal
spot in it's distance from the sun to produce the ideal tempurature, and
various other life preserving conditions.

Base about apex. Life (of this form) was able to evolve here because the
conditions were/are suitable for it to evolve. Fairly obviously it is
only where life evolves that there is the possibility of life-forms
speculating about the coincidences that led to it being possible; there
is no need to invoke a deity.

The usual analogy is the puddle marvelling at the fact that the hole it is
lying in is perfectly shaped just for it ;-).

Klazmon.





SNIP

Llanzlan Klazmon wrote:
The usual analogy is the puddle marvelling at the fact that the hole it
is lying in is perfectly shaped just for it ;-).

Excellent! I must remember that one. Thank you.

Best,
Stephen

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As Richard Feynman said, "...on the way in I saw a licence plate,
AWR102, given the millions of plates around, what are the chances of
seeing that one ? Amazing....."
If coincidences didn't happen, we wouldn't see them.
jc

jc wrote:
As Richard Feynman said, "...on the way in I saw a licence plate,
AWR102, given the millions of plates around, what are the chances of
seeing that one ? Amazing....."
If coincidences didn't happen, we wouldn't see them.


Coincidence does as coincidental is. You think seeing a number plate on
a car is coincidence?

Was it a coincidence he was chosen to look into the destruction of the
shuttle? The only scientist not tied in to the mission?

Or a coincidence that his findings were snowed under? If he was so
great how come the people involved only censured the whistle blower not
the crooks?