jboyler wrote:According to Newton's Law of Gravitation, the force of gravity is related to the masses of the two objects concerned. Mass is not just a matter of size, but a matter of density. Earth is solid rock and has a extremely dense liquid metal core. If Unicron, however, has lots of empty space inside (as I bet he would, if he has lots of moving parts and a huge planet-chomping orifice) he would not be very dense at all, and might actually have less mass than Earth even though his physical dimensions would appear equal or larger.
Firstly Unicron is made of metal, which is denser than rock, and secondly we've no evidence that he is hollow inside to any degree moreso than the Earth is. The Earth has thousands and thousands of caves and passages, so does Unicron appear to.
From what we can see of his transformation process in the movie, comic and in the Ultimate Guide he appears to be incredibly tightly packed in planet mode, and appears to expand outwards in robot mode imo.
That might be why his planet mode is almost invulnerable and his robot mode is weaker.
Thirdly gravitational attraction is directly proportional to the mass and the inverse square of the distance between the two objects, not only mass.
What this means is that while Unicron and a planet would exert a gravitational pull on Earth other, the planet would be affected less, and Unicron would be pulled towards it.
Yes I had guessed.
On a related note, why does Megatron float in front of Unicron? If Unicron had even a fraction of Earth's gravity, wouldn't Megatron "fall" into him? For Megatron to be floating in front of Unicron would require very fast and constantly accelerating retrograde movement on Unicron's part.
Hence our discussion of antigravity.
For Unicron, the biggest problem would be his massive inertia. How does a planetoid-sized being change its direction, accelerate to faster-than-light speeds (neccesary for interstellar travel), and then slow to a stop to munch on a planet?
If he has an antigravity power presumably he can manipulate space like in Star Trek and 'warp' places. Or he might be magic, being a God and all.
It's also interesting to ponder what effect Unicron's gravity would have on the Earth. Even if Unicron had a mass less than that of our moon, his mere presence would wreak havoc on our world. The tidal actions would be unprecedented and the gravitational field and magnetic poles of Earth would be in chaos. He might cause seismic damage, create huge tidal waves, and completely alter our weather patterns (at least temporarily)
Or maybe not. As Unicron appears able to manipulate gravity he can presumably also turn up with no effect whatsoever. We did go through most of this already, if you wanted to read the rest of the topic.
And I still disagree with the statement that Cybertron is as large as Saturn. Even though the comic might say so, every time we see Cybertron it looks very small, more like the size of the Death Star.
But we've no concept of scale unfortunately. What looks small on Cyb might be utterly vast to us. Also Unicron's Transformers Universe entry states that he happily consumes entire stars and his mission is to engulf the Universe.
Now obviously he has some mechanism for dealing with objects much more massive than he is, but he himself would have to be a fair old size to process the matter he would consume from such vast objects at anything like a meaningful rate.
Or again it could just be 'magical God powers'. Coupled with his slurpy field of doom.