ensonik

I suspect it's something along those lines. I guess what I'm hearing is that there are no conclusive explanations for the phenomena.

No, one yawn triggers the next. I'm curious what causes this. Well it's not physical, so yeah. But I'm curious what psychology would account for an immediate involuntary reaction triggered by a sound over the phone.

It's a genuine phenomenon that everyone on the planet observes regularily. One person yawns, and then another person(s) immediately yawns thereafter. It happens over the phone as well. Is there a scientific explantaion for this?

That's the best advice I've read in this thread so far.

The objects in question are the Earth and Moon, right? While I appreciate you pointing me towards a fuller mathematical understanding of gravity, this thread is about two specific bodies and their relationship. So can I assume that my earlier remark about the moon deriving it's pull from the Earth was accurate, or not?

So basically without the Earth the moon would have an extremely weak gravitational pull. It's strong pull in relation to it's mass is essentially derived from object 2 (Earth)?

Good question. I don't know the answer other than to say the obvious thing, which is that it must be comprised of heavier materials.

Orphiolite, great answer. Very in depth and satisying. Can you elaborate on the variance in size and density of planetery bodies in relation to the sun? I understand why the gaseous planets are further away, etc, but am unclear on that lack of linearity in terms of size and gravitational pull of planets as they get further from the sun.

So you're saying the planets are ordered outwards from the sun based on their density/heaviness? So Mercury is the second heaviest thing in the solar system next to the Sun, Venus the third, etc?

Martin, thanks for clearing that up. I guess I held a misconception about the term. So a Hubble volume is essentially a measured distance, and we have the capability to look beyond it. So how far past one H-volume can we see? Into a second or third, or farther?

I've heard this term, but am unclear on it's exact definition. I think it implies that the entire universe as we know it is just one "volume" inside of a larger universe. Is that an even remotely accurate definition?

zigabytes?

lol

That makes sense as I could imagine a dust ring having areas denser then others. I suppose these dense areas could ultimately be drawn together, or collapse as you say. So I guess my next question would be then, why is this process not continually occurring? If particles within a dust cload are naturally drawn together, should we not be seeing this clumping action take place right now all over the visible universe?

So you're saying the gravitational pull that 'hotspots' of dark matter produce could be the foundation on which planets are based? Interesting theory, I'm not sure if there's any truth to it or not. I guess the implication of that would be that planets, including Earth, reside on high concentrations of dark matter.

I posted this in another thread without response, so I'll try again: What is the current explanation for why random particles within a nebula would in fact be drawn together towards an empty spot in space to eventually form a planet? What is the "motivation" so to speak for random particles to form together at some arbitrary point?

Thinking about this some more, and I can't help but imagine that particles attracted together by gravity within a nebula would form a uniform spherical surface. So is it off base to assume that prior to disruptions caused by plate techtonics and so forth, the earth was uniform? And speaking of the creation of planets, what is the current explanation for why random particles within a nebula would in fact be drawn together towards an empty spot in space to eventually form a planet? What is the "motivation" so to speak for random particles to form together at some arbitrary point?

The USGS link is very informative, thanks.

So would the Eath's terrain have been uniform around the entire sphere prior to any natural disasters?

Aren't orbits due to the interplay between multiple forces? Your example cites only one.

Simple question: Why are large parts of the planet flat, while others are raised and mountainous? Is it related to climate and wind/rain errosion over enormous emounts of time, or was the planet just formed this way?