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dapted
2002-Apr-13, 04:04 PM
I've been looking at tidal lock between the earth and the moon. There are a number of sites that explore it. I think I understand the concept which could eventually lead to earth having a ring, instead of a moon. It leads me to wonder about tidal lock between the sun and any planets.

My question is whether there is a tidal lock situation between the sun and any of the planets that could lead to a planet becoming a ring of rubble orbiting the sun.

Isn't there a ring of what some call a planetary reminant in orbit between the orbits of a couple of our planets already? Could that rubble have been caused by a tidal lock between the sun and that planet?

If anybody knows of sites or studies looking at that possibility I'd be interested.

Dan

GrapesOfWrath
2002-Apr-13, 05:07 PM
I'm not sure of which connection between tidal lock and ring formation--do you have links to a few of those websites?

The asteroid belt (http://www.planetscapes.com/solar/eng/asteroid.htm) is such a ring of small-sized rubble around the Sun, and some theories do think of it as a proto-planet.

Mercury (http://www.planetscapes.com/solar/eng/mercury.htm) was once thought to be locked to the Sun, but now it is observed to be in a 3:2 resonance. That's why its day is twice as long as its year!

2002-Apr-16, 08:36 PM
not trying to avoid an inportant issue
i'll tap in with my version of "astroid`s BELT"
sure there was once a planet there and all that left are
just bits & pieces.. so it was Obliterated and
not so long ago [according to me] it held an
advanced culture as did a Large planet in the
Mars orbital which completely vanished in the
same interplanetary war. Astrolopolis vs MarsFellow
ike I said Marsfellow diapeared, period
so the Asttrolopians had the best weapon, but Marsfellowites were capable of obliterating Astrolopolis, and they did befor vanishing.

2002-Apr-16, 08:46 PM
Anyway1: the war between Astrolopious &
Marsfellow was of course the Main event
of the Solar System history {for all time}
and one side effect of that events Earth's
Moon, {which according to me A Lone} came
into being on that very Average Orbital Number
of astrolopolis ?{8 years}
Anyway2: a pair of BIG HUNKS of astrolopolis
on a decent path twards the Sun came upon
Earths orbit.. the smaller ofthe two {LEAD}
actually colided with a fractured Earth
and the larger piece {following} passed by close enough
thta it provided the force necessary to FORCE{insert} the Moon into orbit. Ahh.. Mention Me Not as really I don't give a HOW t.`N

Bob
2002-Apr-16, 09:04 PM
[quote]
On 2002-04-13 13:07, GrapesOfWrath wrote:
I'm not sure of which connection between tidal lock and ring formation--do you have links to a few of those websites?

The Bad Astronomer himself in his bitesize on tides referenced this interesting link: http://www.jal.cc.il.us/~mikolajsawicki/tides_new2.pdf

On pps. 9-10 the author states that tidal lock between earth and moon is not the final steady state. From this configuration solar tides will speed the earth's rotation, conservation of momentum will force the moon's orbit ever lower until it reaches the Roche limit and disintegrates into a ring. I'm still mulling this over because I haven't seen this scenarion elsewhere. The article is otherwise a very good one, however.

aurorae
2002-Apr-16, 09:24 PM
On 2002-04-16 17:04, Bob wrote:

On pps. 9-10 the author states that tidal lock between earth and moon is not the final steady state. From this configuration solar tides will speed the earth's rotation, conservation of momentum will force the moon's orbit ever lower until it reaches the Roche limit and disintegrates into a ring. I'm still mulling this over because I haven't seen this scenarion elsewhere. The article is otherwise a very good one, however.


I remember reading the Triton will eventually move closer to Neptune and someday reach the Roche limit.

I suspect this is reasoned because Triton is likely to be a captured moon, which is why it orbits backwards. I suspect there is also some math and physics involved. /phpBB/images/smiles/icon_smile.gif

dapted
2002-Apr-17, 05:37 AM
Sorry, the pages I am looking for are no longer there. One was on the NASA Glenn site and much of that was closed due to 911. I don't see the connection to terrorism, but hey, I don't understand a lot of things I know? The other links were on another space BBS but their archives don't go back that far.

GrapesOfWrath
2002-Apr-17, 08:28 AM
On 2002-04-16 17:04, Bob wrote:
The Bad Astronomer himself in his bitesize on tides referenced this interesting link: http://www.jal.cc.il.us/~mikolajsawicki/tides_new2.pdf

On pps. 9-10 the author states that tidal lock between earth and moon is not the final steady state. From this configuration solar tides will speed the earth's rotation, conservation of momentum will force the moon's orbit ever lower until it reaches the Roche limit and disintegrates into a ring. I'm still mulling this over because I haven't seen this scenarion elsewhere. The article is otherwise a very good one, however.


That is an interesting link. Thanks.

Part of the reason you may not have seen that scenario elsewhere is because the time it would take to get to that point is greater than the predicted age of the Sun and solar system. I'll take some time to mull it over too!

Small nit. Just past equation 14, on page 7, he computes the effect of the moon on the weight of an average person of 80 kg, and states that it is 2.0 x 10^-4 N, but then he goes on to say that that would be 20 micrograms on a scale calibrated in kg. Actually, it is 20 milligrams.

2002-Apr-17, 10:51 AM
<a name="20020417.4:37"> page 20020417.4:37 aka Kg
On 2002-04-17 04:28, GrapesOfWrath wrote: To?


http://www.jal.cc.il.us/~mikolajsawicki








20 micrograms on a scale calibrated in kg. Actually, it is 20 milligrams.
4:41 A.M. HUb' ahha attention to detail..{hmm?}