(urth) What's So Great About Ushas?

[Jeff Wilson]

Dave Tallman wrote:
> There are two possible mechanisms for the white hole to disrupt
> earth: thermal and gravitational. I believe the gravitational effects
> were practically nothing: Baldanders only expected them to ring
> bells. He predicted the Urth would have problems due to rising sea
> levels (ice plus energy gives water) and to the heat causing shifts
> in the earth's crust. The latter is hard to understand, but I suppose
> some unstable faults could be triggered by changes in heat.
> 
> 
> If the gravitational effects were really severe for either the white
> or the black hole, then the Earth's orbit would be perturbed. We have
> no hint that this was the case, and if it were it would cause even
> more severe problems for Ushas.


Urth's orbit is already perturbed by the process of moving of Lune 
closer to it. The White Fountain could be of similar mass to the moon, 
which produces the majority of tides on the earth, and approach much 
more closely to create much more violent tides, but still not alter the 
overall orbit of the earth as much, because it is only about 1/80 of the 
  earth's mass, like the moon is.


While direct gravitational force drops off as the inverse square of 
distance and irrespective of size, the derived tidal forces drop off 
with the inverse cube of distance, making distance much more important, 
but increase with in proportion to the size of the object, making bells 
tinkle, mountains buckle, and planets sunder. You can see for your self 
here

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

where the final equation plainly has a total of 3 powers of R (distance 
radius) in the denominator, and delta r (the radius of the far object) 
in the numerator.

-- 
Jeff Wilson - jwilson at io.com
< http://www.io.com/~jwilson >