My Brief Essay
I want, here, to adress several issues and criticisms of my work so that people might better understand what I have done and why. The first problem some people might have is questioning just how I know what the asteroid is composed of. For starters I have quotes such as Dengar’s from “Tales of the Bounty Hunters” which indicates the asteroids in the field where Nickel-Iron ones. However the movies always contradict the novels so I went amnd looked for as much visual data as I could possibly collect. As part of my hunt I found this very useful site:
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From http://seds.lpl.arizona.edu/nineplanets/nineplanets/asteroids.html
S-type, 17%: relatively bright (albedo .10-.22); metallic nickel-iron mixed
with iron- and magnesium-silicates;
M-type, most of the rest: bright (albedo .10-.18); pure nickel-iron.
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The asteroid is visibly
reflecting light on par with the hull of the ISD visible thus I take this to
mean the albedo is in the upper range. Now we have narrowed our options but
these ranges include everything from pure Ni-Fe to a range of Silicates so lets
look at color and opacity. Obviously the asteroid is opque so we need opaque
minerals, equally obvious there are at least two visible asteroid color groups.
The first is a brownish-red asteroid coloration (the one in question) and the
other is a silver-gray asteroid coloration (its nearest neighbor). With this in
mind I set off to find minerals that could match this rough composition. It is
here that I must note that I do NOT have a spectrometer and do not claim that
this is the most precise spectrum analysis rather I believe that with the
avaliable data I have taken the only possible course so as to reconcile the
imagery with real life mineral data. I also wish to note that for the record I
examined all minerals I could find which were opaque, fell under the groups for
S-Type asteroids (and M-Type), and which were of a range of colors from rust
browns to earth reds. From this list I found the following minerals which are
brownish in color family, opaque, and either iron or magnesium silicates, I do
not assert this is the definitive list but if someone would care to find others
I would thank them greatly. Anyway the link below will take you to the point of
data collection where you can view the same evidence I had.
http://www.webmineral.com/determin/opague_minerals.shtml
Now with at least semi-solid
data on the possible composition I set out to calculate the vaporization energy
for an asteroid of given size. This is where things got complicated. I
basically performed a calculation on the energy required as if the asteroid
were purely composed of one mineral, this will give us a range of solutions
presenting an absolute minimum as well as a likely range for the true minimum
to reside in, a point we can not know without having an exact spectrographic
analysis of the asteroid, something I believe none of us is equipped to do.
Also I must state that my calculations are based on an element by element melt
and vaporization in succession so there are several factors which will
definitely skew my results including the simple fact that there is no readily
avaliable thermodynamic data on the minerals in question.
This is the reason why I will be furthering this analysis in version 2.3 by focusing on a new asteroid, one that is of a color spectrum more in line with pure Ni-Fe composition (the last asteroid). As an aside the average of the values would be 1418 TJ though that number has no real bearing it should serve as a good starting point for firepower calculations until version 2.3 comes out. Again this is a conservative estimate based limiting factors like:
1) The asteroid is never seen properly on plane so the
absolute dimensions might be slightly larger than presented figures.
2) This analysis completely ignores the energy necessary to fracture the
actual mineral structure found in asteroids so there is an added dimension
of mechanical energy unaccounted for.
A second
common criticism has been of my choice of 150K as a starting temperature. I
have been criticised for using this figure by certain persons who have stated
that asteroids within our own solar system have been known to have much higher
starting temperatures and that the core temperature exceeds that of the outer
layers. The later I cannot deal with sans creating a differential equation
model of the mass versus temperature gradient, something which serves little
purpose compared to taking an assumed average temperature with justification.
Now I have been doing research into asteroid formation and structure courtesy
of the McKeldin Library, College Park MD and the Howard County Central Library,
Columbia MD. After perusing "Comets, asteroids and, meterorites" by
Time Life Books, ISBN/ISN 0809469057/0809469049 I came to the rather startling
conclusion that, much as I had assumed, asteroids lose heat rapidly enough (on
the order of 25 + degrees per million years core temperature) and that
continued higher temperatures are due to things like solar heating (minimal)
and radiogenic heating (which isn't present in Ni-Fe asteroids and other
asteroids composed entirely of stable light elements). Anyway I have no doubt
that a formation such as the Hoth Asteroid field would be at least the 67
million years old neccessary to drop from the melting point of Iron to 150 K.
Beyond this pure Ni-Fe asteroids are known to lose heat even faster (upwards of
125 degrees per million years) which would require a liftetime of only 13.3
million years. Basically I see no convincing proof that an equilibrium
temperature in deep space, well away from Hoth or Anoat's sun, would be
signifiantly greater than the figure quoted.
Lastly I wish to address why I
included Oxygen and Hypdrogen in the elemental makeup but did not provide data
on melting and vaporization. I noticed very early on that the energies and
temperatures neccessary to vaporize oxygen and hydrogen were extremely low, an
assumption I had already made but the data was reassuring. As such I realized
that calculating them would add nothing as the total energy neccessary to
vaporize even the large amount of oxygen found in Neotocite and
Magnesiocummintonite would be a half dozen orders of magnitude smaller than the
energy requirements for any other element and were I being more strict about
significant figures they would be cancelled out. As such I have not included
them in this calculation.
As with all versions before criticism and comments are welcome.