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Beach rocks and Asteroids



 
 
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  #1  
Old May 30th 08, 02:38 PM posted to alt.astronomy
G=EMC^2 Glazier[_1_]
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Default Beach rocks and Asteroids

They have the same features. No sharp edges. Smooth surface. We now
why this is for rocks on the beach,but how about these space rocks"?
Did space dust do the erosion? Did space dust also create these
asteroids? Asteroids have surface dust,as shown by the craters filled
in. The asteroid belt that is between Mars and Jupiter tell me that
happened to be the place where two rock planets collided. Since I have
yet to see a sharp edge asteroid that means no resent collisions. I
wonder if all those asteroids have the same thickness of dust.? I
wonder how fast they spin in relation to one another? It is amazing
that asteroid Ida can have its own moon. Asteroid Gaspa has all those
craters Reality is I can relate Gaspa with those two moons of
Mars. Shape and all Bert

  #2  
Old May 31st 08, 11:43 AM posted to alt.astronomy
Ron Miller
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Posts: 63
Default Beach rocks and Asteroids

On May 30, 9:38 am, (G=EMC^2 Glazier) wrote:
They have the same features. No sharp edges. Smooth surface. We now
why this is for rocks on the beach,but how about these space rocks"?
Did space dust do the erosion?


In a sense, yes. Much of it is the result of micrometeorite erosion.

Did space dust also create these
asteroids?


Only in the sense that they are the result of the same process of
accretion as the rest of the planets.

Asteroids have surface dust,as shown by the craters filled
in. The asteroid belt that is between Mars and Jupiter tell me that
happened to be the place where two rock planets collided.


It is more likely that the asteroids are left-over debris from the
early solar system. There is certainly no evidence that there were
once two rocky planets that collided, creating the asteroid belt.

Since I have
yet to see a sharp edge asteroid that means no resent collisions. I
wonder if all those asteroids have the same thickness of dust.? I
wonder how fast they spin in relation to one another?


They rotate at many different rates.

It is amazing
that asteroid Ida can have its own moon.


Why?

R

  #3  
Old May 31st 08, 01:39 PM posted to alt.astronomy
G=EMC^2 Glazier[_1_]
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Posts: 10,860
Default Beach rocks and Asteroids

R Nice answers The reason Ida amazes me having a Moon is their mutual
gravity being such a small force would make capture very hard to achieve
Go figure Bert

  #4  
Old May 31st 08, 03:02 PM posted to alt.astronomy
BradGuth
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Posts: 21,544
Default Beach rocks and Asteroids

The electrostatic charge of several teravolts is common place, similar
to the electrostatic charge of our physically dark and extremely dusty
moon. Big and often equally nasty secondary stuff gets picked up
along the path, and it all gets into a massive grinding ball of rocks
that continually work away at the higher density core. Some of these
comet/meteor cores are of nearly solid iron, thorium and other heavy
elements, and a core like that (such as the 700 meter core of 45P/
Honda) in a combined head on velocity encounter could easily penetrate
the crust of Earth, especially if any part of its 70 km ball of rocks
and dust is what first liquefies the surface of Earth to start off
with.

http://www.lpl.arizona.edu/impacteffects/

An asteroid or rogue planetoid (like our moon used to be) might be a
whole lot easier to deal with any any cluster of massive rocks.

.. - Brad Guth


G=EMC^2 Glazier wrote:
They have the same features. No sharp edges. Smooth surface. We now
why this is for rocks on the beach,but how about these space rocks"?
Did space dust do the erosion? Did space dust also create these
asteroids? Asteroids have surface dust,as shown by the craters filled
in. The asteroid belt that is between Mars and Jupiter tell me that
happened to be the place where two rock planets collided. Since I have
yet to see a sharp edge asteroid that means no resent collisions. I
wonder if all those asteroids have the same thickness of dust.? I
wonder how fast they spin in relation to one another? It is amazing
that asteroid Ida can have its own moon. Asteroid Gaspa has all those
craters Reality is I can relate Gaspa with those two moons of
Mars. Shape and all Bert

  #5  
Old May 31st 08, 03:10 PM posted to alt.astronomy
BradGuth
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Posts: 21,544
Default Beach rocks and Asteroids

On May 31, 3:43 am, Ron Miller wrote:
On May 30, 9:38 am, (G=EMC^2 Glazier) wrote:

They have the same features. No sharp edges. Smooth surface. We now
why this is for rocks on the beach,but how about these space rocks"?
Did space dust do the erosion?


In a sense, yes. Much of it is the result of micrometeorite erosion.

Did space dust also create these
asteroids?


Only in the sense that they are the result of the same process of
accretion as the rest of the planets.

Asteroids have surface dust,as shown by the craters filled
in. The asteroid belt that is between Mars and Jupiter tell me that
happened to be the place where two rock planets collided.


It is more likely that the asteroids are left-over debris from the
early solar system. There is certainly no evidence that there were
once two rocky planets that collided, creating the asteroid belt.

Since I have
yet to see a sharp edge asteroid that means no resent collisions. I
wonder if all those asteroids have the same thickness of dust.? I
wonder how fast they spin in relation to one another?


They rotate at many different rates.

It is amazing
that asteroid Ida can have its own moon.


Why?

R


Stuff of large rock does go bump in the night.

Given the minor 7.5e9 kg for the 8P/Tempel-Tuttle, plus its
substantial cloud and trail of nasty rocks (minus a 2+ kg worth of P8/
Tuttle rocks that I now have), subsequently having been confirmed that
the main or parent comet was 45P/Honda-Mrkos-Pajdusakova, whereas
according to team Hubble 45P/Honda is losing dust/(small rocks) at the
impressive rate of 86 tonnes per day. We can safely assume the outer
most dust or comet tail of such rocks that have encountered Earth as
meteorites being those of the least composite density, because items
of greater density would tend to stick with the massive core of
extensively iron, nickel and thorium (possibly a composite density of
9000 kg/m3).

A few teravolts of charge should also help attract and hold onto the
surrounding debris.
.. - Brad Guth
  #6  
Old June 1st 08, 04:42 PM posted to alt.astronomy
Painius Painius is offline
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Posts: 4,144
Default Why does Mars spin so slowly? (was - Beach rocks and Asteroids)

"Ron Miller" wrote in message...
...
On May 30, 9:38 am, (G=EMC^2 Glazier) wrote:

They have the same features. No sharp edges. Smooth surface. We now
why this is for rocks on the beach,but how about these space rocks"?
Did space dust do the erosion?


In a sense, yes. Much of it is the result of micrometeorite erosion.

Did space dust also create these
asteroids?


Only in the sense that they are the result of the same process of
accretion as the rest of the planets.

Asteroids have surface dust,as shown by the craters filled
in. The asteroid belt that is between Mars and Jupiter tell me that
happened to be the place where two rock planets collided.


It is more likely that the asteroids are left-over debris from the
early solar system. There is certainly no evidence that there were
once two rocky planets that collided, creating the asteroid belt.

Since I have
yet to see a sharp edge asteroid that means no resent collisions. I
wonder if all those asteroids have the same thickness of dust.? I
wonder how fast they spin in relation to one another?


They rotate at many different rates.


'Lo Ron, LTNS --

Yes, this is true, however scientists still consider these
spin rates to be highly "isochronous", which just seems
to mean that their spin rates vary a lot less than might
have been previously expected, and that the rates are
not a function of the sizes of the asteroids. If you check
the list toward the bottom of this web page...

http://history.nasa.gov/SP-345/ch9.htm

you'll see that the rates are (generally) not much off
from the spin rates of Jupiter and Saturn. So these
rates probably don't vary much from the original spin
rates billions of years ago.

The inner planets would also be spinning at these much
faster rates if it weren't for the influence of the relatively
nearby Sun and, in the case of Earth, the Moon. And in
the category of "Things that are fascinating and
inexplicable about the Solar System", how is it that Mars
rotates so slowly? The spin rate of Mars is almost the
same as that of our planet, Earth. But Earth had the tidal
friction of a large planetary body nearby to slow it down.
So what slowed Mars down to almost the same rotation
speed as Earth?

happy days and...
starry starry nights!

--
Indelibly yours,
Paine

P.S. Thank YOU for reading!

P.P.S. Some secret sites (shh)...
http://painellsworth.net
http://savethechildren.org
http://eBook-eDen.secretsgolden.com



  #7  
Old June 1st 08, 04:57 PM posted to alt.astronomy
G=EMC^2 Glazier[_1_]
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Posts: 10,860
Default Why does Mars spin so slowly? (was - Beach rocks and Asteroids)

Painius I find the 3mph rate of spin of Venus most amazing Bert

  #8  
Old June 1st 08, 11:06 PM posted to alt.astronomy
Painius Painius is offline
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Posts: 4,144
Default Why does Mars spin so slowly? (was - Beach rocks and Asteroids)

"G=EMC^2 Glazier" wrote in message...
...

Painius I find the 3mph rate of spin of Venus most amazing Bert


I could be wrong, Bert, but i have this covered in my
mind by the Sun. Both Venus' and Mercury's rates are
mainly affected by their close relative proximity to the
Sun.

Here's how it pans out...

Mercury is so close to the Sun that one would think it
would be nearer to being "locked in" than Venus is.
And there are some astronomers who believe that
Mercury actually *is* tidal-locked to the Sun, but in a
3:2 lock instead of a 1:1 lock. This just means that
they think the reason that the ratio of the orbital
period to the rotation rate is 3/2 is because of the
highly eccentric orbit of Mercury. And so because of
this, because Mercury's orbit is somewhat elliptical,
then Mercury must be tidally locked to the Sun in a
3:2 lock.

What i think science hasn't caught up with is the
probability that the rotation rates don't just decrease
to the "lock-in" rate and then stay there.

So instead of just decreasing and locking in, what do
you suppose the rotation rates actually do?

In my mind, before the spin rate "locks in", it gets
even slower, decreases to "actual" zero rotation, and
then may begin to increase in the opposite direction.
This increase continues for a time, then begins to slow
down again. It passes through "actual" zero spin rate,
and then begins to increase again until it equals the
"lock-in" rate. Then it continues to increase for awhile
until it reaches a point where it begins to decrease
again.

These "oscillations" of spin rate and direction slowly
dampen out over time until the object actually does
"lock in" to a synchonized orbit. At this point, all that
remains of the "oscillations" are what astronomers
call "librations". The smaller object sort of "rocks" to
and fro, or back and forth, with respect to the larger
body. Our sister planet, Selene (the Moon) does this...

http://en.wikipedia.org/wiki/Lunar_libration

Mercury today rotates with a spin rate of about 58.5
Earth days, and its spin direction is the same as our
Earth. The time it takes for Mercury to make a full
orbit around the Sun is about 88 Earth days. Planet
Mercury spins in a counter-clockwise direction as you
look down on its North pole. Not all that long ago it
was thought that Mercury was tidally-locked to the
Sun, that its rotational period was the same as its
orbital period (88 days). It was a bit of a shock for
astronomers to find out that Mercury does actually
rotate with respect to the Sun.

Venus, as you know, is very different, because the
rotation rate of Venus is 243 Earth days, and Venus
orbits the Sun in about 244.5 Earth days. At first
glance, it seems that Venus is almost exactly tidal-
locked to the Sun. And if Venus were rotating in a
counter-clockwise direction like all the other planets,
then it would be almost exactly tidal-locked. But, the
spin direction is opposite that of Mercury, Earth and
all the other planets. The spin direction is clockwise
as you look down on Venus' North pole.

So my idea is that, while Mercury has probably gone
through one or more cycles of slowing to zero, then
increasing again, and will eventually slow back down
and finally "lock in" to the Sun, Venus must still very
slowly decrease its clockwise spin and then begin a
counter-clockwise direction of spin to eventually
"lock in" to the Sun.

So both planets, Venus and Mercury, are fairly close
to being tidally locked to the Sun. It probably takes
many years to note any change in the spin rates of
Mercury and Venus, but my contention is that if such
a study is ever launched by science, it will be found
that the spin rates of these two are slowly, slowly
changing.

Below is a scale showing different rotation rates in
Earth days for Venus over time...

-200 -250 -300 . . . 0 . . . +300 +250 +200
^ ^
NOW LOCK

As the number of Earth days increases, the actual
rate of rotation of Venus decreases. As you can see,
at present, Venus is rotating at minus 243 days. So
Venus would have to decrease its rate of rotation
down to zero, and then begin to increase spin in the
opposite direction until it reaches plus 225 days (the
same as its orbital period). All i'm saying is that
Venus (or any smaller body) will probably go back
and forth past the "lock" point, carried past the point
each time by the rotational momentum. With each
crossing the spin speed will "flip" closer and closer to
the "lock" point until the body finally "locks in" at the
same rotational speed (in a counter-clockwise
direction) as the orbital period.

Mercury's scale looks like this...

-150 . . . 0 . . . +150 +125 +100 +75 +50 +25
^ ^
LOCK NOW

So Mercury appears a bit closer to being tidally
locked to the Sun than Venus. It only has to slow
down to a spin period of 88 Earth days. The catch
is that this hasn't been studied as far as i know, so
it may be that Mercury has passed through the lock
point and is still increasing its rotational speed. It
might take several years of study to determine
which is the case.

If i'm right, then Venus' spin rate of almost one
complete rotation in a clockwise direction during
one complete revolution around the Sun is not at
all mysterious. It might just mean that Venus is
slowly tidal locking to the Sun, but is presently in
a retrograde spin that changes and will eventually
bring Venus closer and closer to being tidal-locked.

happy days and...
starry starry nights!

--
Indelibly yours,
Paine

P.S. Thank YOU for reading!

P.P.S. Some secret sites (shh)...
http://painellsworth.net
http://savethechildren.org
http://eBook-eDen.secretsgolden.com


  #9  
Old June 2nd 08, 01:44 PM posted to alt.astronomy
G=EMC^2 Glazier[_1_]
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Posts: 10,860
Default Why does Mars spin so slowly? (was - Beach rocks and Asteroids)

Painius I find your rotation thinking very interesting. Especially
Venus rotation around the Sun is so close in time with its spin. Do you
thing Venus's thick atmosphere has slowed its spin? Maybe "once upon a
time" Venus was much closer to the Sun Its about 67,000,000 miles away
at this spacetime. Bert

  #10  
Old June 3rd 08, 01:57 PM posted to alt.astronomy
G=EMC^2 Glazier[_1_]
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Posts: 10,860
Default Beach rocks and Asteroids

Looking as I type at all those rocks on Mars surface. They look like
beach rocks or the old ones do. Reality is you can tell the old from the
young by the amount of erosion Bert

 




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