The Earth once had an ice ring?

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A Dyson Ring the simplest form of the Dyson Sphere. Hoagland is suggesting in the video that parts of Saturns B-ring could be a piece of a Dyson Ring ...if this is true it would be mind melding! Interresting topic

[Johnsmith Profile]

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With this ring, I thee shred, by Phil Plait

Earth with rings image courtesy Damien Bouic.

First, could Earth have rings? Sure! It’s unclear exactly how Saturn (or the other four outer giant planets) got their rings, but there is more than one mechanism to create them. A small moon could get hit by an asteroid or comet, shattering it. An impact on the Earth itself, if it were big enough, could create rings (the impact that formed the Moon billions of years ago may have done just that). That would kinda suck for us, though. Saturn’s moon Enceladus has geysers which may resupply the planet’s A and E rings (though that’s more of a replenishment than actually creating them).
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[Sheeple Profile]

Could we not imagine that the Earth, exactly like Saturn, once had a ring? It might have arisen from its outer layer precisely as Saturn’s did and have maintained itself a long time, since the Earth had gone from a much faster rotation than the present one to the existing rate, for who knows what reasons. Or we could attribute the building of it to the common basic material sinking down according to the rules which we explained above, which we must not take so strictly if we want to indulge in our liking for the unusual. But what a supply of beautiful explanations and consequences such an idea offers us! A ring around the Earth! How beautiful the sight for those who were made to live on Earth as a paradise. How much comfort for those whom nature was to greet with a smile on all sides! But this is still nothing in comparison to the confirmation which such a hypothesis can derive from the ancient lore of the creation story, no small recommendation for approval among those people who believe they are not dishonouring revelation but endorsing it when they use it to ennoble the excess displays of their wit. The waters of the firmament, which the Mosaic account talks of, have already caused interpreters no small problem. Would it not be possible for us to use this ring to assist ourselves out of this difficulty? This ring undoubtedly consisted of vapours rich in water. And in addition to the advantage which it could provide for the first inhabitants on the earth, we have the fact that it was, when necessary, capable of breaking apart in order to punish the world, which had made itself unworthy of such beauty, with deluges. Either a comet, whose power of attraction brought the rule-bound movements of ring’s parts into total confusion, or the cooling in the region where it was positioned united its scattered vapour particles and hurled them down upon the ground in the most horrifying of all inundations. We understand readily what the consequences of this were. The whole world went under water and absorbed, in addition to the foreign and volatile vapours of this unnatural rain, that slow poison which brought all creatures closer to death and destruction. From now on the shape of a pale light bow vanished from the horizon, and the new world, which could never remember what this looked like without experiencing terror before this fearful instrument of the divine revenge, saw perhaps with no less dismay in the first rainfall that coloured bow which seems to develop its shape like the first one, but which through the covenant of a forgiving heaven was to be a sign of grace and a memorial to the lasting establishment of the now changed surface of the Earth. The similarity in the form of this memorial sign to the event I have described could make such a hypothesis appealing for those people who follow the prevailing inclination to bring the wonders of revelation into one system with the orderly laws of nature. I find it more advisable completely to sacrifice the transitory approval which such agreement can arouse for the true pleasure which comes from the perception of regular interconnections when physical analogies reinforce each other in the designation of physical truths.

[Sheeple Profile]

Ice asteroids likely source of Earth's water: study
by Marlowe Hood, Wed Apr 28, 8:02 pm ET, PARIS (AFP)

Astronomers have for the first time detected ice and organic compounds on an asteroid, a pair of landmark studies released on Wednesday says.

The discovery bolsters the theory that comets and asteroids crashing into Earth nearly four billion years ago seeded the planet with water and carbon-based molecules, both essential ingredients for life.

Working separately, two teams of scientists using NASA's Infrared Telescope Facility in Hawaii found that the 24 Themis, which orbits the Sun between Mars and Jupiter, is literally covered in a thin coating of frost.

It had long been suspected that the massive space rocks that bombarded our planet after the formation of the solar system contained frozen water, but the two studies, published in Nature, provide the first hard evidence.
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See also: http://en.wikipedia.org/wiki/24_Themis.

[Sheeple Profile]

In the past, the Earth must have been rotating much faster for a reduced gravity on the surface to allow the existence of the heavy dinosaurs.

The current equatorial rotation velocity is vc = 1674.4 km/h (465.1 m/s).

What would roughly be the rotation velocity needed to experience weightlessness on the surface?

mv^2/R = mg, or v = sqrt(gR), with g = 9.8 m/s^2 and R = 6378 km,
then v = 7906 m/s, and v/vc = 7906/465.1 = 17,
so if the Earth makes one full day/night cycle for 24/17 = 1.41 hours,
we would be floating in the air.

Any time duration between 1.41 hours and 24 hours would result in reduced gravity.

One hypothesis is that after the Moon was captured by the Earth, the rotation velocity was reduced and the increased gravity killed the dinosaurs.

This is just an illustration, the math is not that simple though, as a hint think to what extent the gravity would increase if the Earth stood still.

[Johnsmith Profile]

The Earth's day has increased in length over time. The original length of one day, when the Earth was new about 4.5 billion years ago, was about six hours as determined by computer simulation.
It was 21.9 hours 620 million years ago as recorded by rhythmites (alternating layers in sandstone). This phenomenon is due to tides raised by the Moon which slow Earth's rotation. Because of the way the second is defined, the mean length of a day is now about 86,400.002 seconds, and is increasing by about 1.7 milliseconds per century (an average over the last 2,700 years). See tidal acceleration for details.

Sheeple, according to your oversimplified logic (assuming that the entire mass of the planet is concentrated in a single material point which is not the case),
g_still - v^2/R = 9.8 m/s^2,
(465.1 m/s)^2/6378000 = 0.03991 m/s^2,
g_still = 9.83991 m/s^2.

Then
g_620mln_yrs_ago = g_still - v^2/R = 9.83991 - (465.1 m/s x (24hrs/21.9hrs))^2/6378000 = 9.7991 m/s^2,
and such a small change of the g constant is not really noticeable.

So far, there is no official geological record to support a very fast rotation of the Earth during the time of the dinosaurs.