Natural Science Forum / Physics / Fusion / January 2005

Well, I'm betting that the Deep Impact Probe will go nuclear.  It's
this simple, The Z Pinch machine at Sandia laboritories fires a metal
plate at 28KM/s and the impactor NASA built for the Probe will be
slamming into a comet at 10KM/s.

Here's why, the plate is much more massive than those used at Sandia
and Livermore labs.  Second, we don't know what the comet is made of
but, isotopes are prevailent in meteors, and some don't exist anywhere
else.  Third, they are typically the atomic weight of these isotopes
are much higher than the hydrogen isotope deterium used in the Z Pinch
machine at Sandia.

Below is a copy of the artcle I found and a link to it.  It mentions
details

http://newton.ex.ac.uk/aip/physnews.587.html

HYDROGEN AT EXTREMELY HIGH PRESSURES, upwards of a million times that
on the Earth's surface, can now be produced in physics laboratories.
Understanding hydrogen's behavior under such extreme conditions answers
questions about the interior of Jupiter, provides coveted information
on designing optimal fuel pellets for fusion energy, and yields
information on aging nuclear weapons without having to test them.
Reporting at the Albuquerque meeting, two national labs are producing
seemingly contradictory high-pressure data on the universe's most
abundant element. Using Sandia's Z machine, which runs tremendous
amounts of electric current to generate very high magnetic fields,
researchers (Marcus Knudson, 505-845-7796, mdknuds@sandia.gov) launch a
metal plate that travels at high speeds (up to 28 km/s, making it the
fastest gun in the world) towards a target containing low-temperature
deuterium molecules (D2). The impact of the plate launches a shock wave
that compresses D2 to up to megabars of pressure. Deuterium, a
neutron-containing isotope of hydrogen, is used because its higher
density enables it to be compressed to much higher pressures than
ordinary hydrogen. The Livermore experiments, on the other hand, used
the high-power (and recently decommissioned) Nova laser to shock
compress liquid D2. The Livermore researchers (Robert Cauble,
925-422-1174, cauble@llnl.gov) find D2 to be much more compressible
than do the Sandia researchers. At a million atmospheres, for example,
Livermore finds the D2 to be compressed by a factor of 6 while Sandia
sees a compression of a factor of 4. If the Livermore results are
correct, then there is more metallic hydrogen in Jupiter's interior
than previously thought and it is easier than expected to trigger
self-sustaining nuclear fusion in deuterium fuel pellets, since they
would be more compressible. If the Sandia results are right, then more
traditional assumptions hold. But it's also possible, Cauble says, that
both results are right (each group's compression occurs in slightly
different time scales). As a final possibility, Cauble and Knudson
admit, both results could be wrong (they are both relatively new
techniques). These possibilities are being carefully explored in
conjunction with computer simulations of high-pressure hydrogen, which
require the fastest available computers in the world. The question is
likely to be settled with further experimental research, including more
data from Sandia and future laser experiments, possibly occurring at
Rochester's Omega facility. The ultimate goal of these experiments is
to determine hydrogen's equation of state, the interrelationship
between such properties as its pressure and temperature, at these
high-pressure conditions. Such information can provide information on
such things as the intriguing possibility that gas-giant Jupiter has a
solid-rock core.

Now, this link leads to NASA's web page and gives you the velocity of
the MASS impactor, and the calculated equivalent of TNT it would
produce.  But, that figure is based upon intertia and mass, not a
nuclear reaction.  4.8 Ton of TNT is a shortfall by a long shot.

http://deepimpact.umd.edu/disczone/challenge_massenergy_A.html

The Z pinch machine.
http://www.physlink.com/News/112304ZCrystal.cfm

Z produces one to two million joules of X-rays in 100 to 200 terawatt
bursts. The crystals reflect at either 6.648 or 2.015 angstroms.

That little tiny crystal in joules dictates you multiply 4.8 Tons of
TNT by nearly 10^12

I admit that the multiplier concerning the number of tons is very high
but, when you consider the velocity of piece of foil moving at 28 Km/s
that is smaller than a dime.  When you increase the thickness of the
foil to a point that it has 3 times the mass, 3 times the pressure will
be exherted on the target.  Likewise, when the mass of the projectile
is 3 times greater and the velocity is one 1/3rd or only about 10 Km/s.
You would still end up with 1 million Kilobars of pressure on the
target.  That's why rubber bullets are used for crowd control.  They
are much lighter than lead, and the pressure of impact is much lower
therefor the dammage to the target is much less.  In fission or fusion
experiments, pressure has to do with compressing the nucli of a
material until atoms nucli are colliding.

Look at this picture from this link
http://www.physlink.com/News/112304ZCrystal.cfm

That is the target and the foil projectile isn't much bigger than the
little cup he has his finger in.

Okay, at the bottom of this article is a formula used to calculate
impact pressure.
http://www.newton.dep.anl.gov/askasci/phy00/phy00837.htm  Below I've
copied the part of the article I'm writing about.

Dr. Ken Mellendorf
Physics Instructor
Illinois Central College
=====================================================
The unit N/mm^2 is a unit of pressure (force/area). Here are some of
the
conversion factors:
1N/mm^2 = 9.87 atm = 7500 mmHg = 145 p.s.i.
Indeed, it is quite a high pressure. The following web site is very
useful.
As advertised it converts most anything into anything:
http://www.onlineconversion.com

Vince Calder
=====================================================

I can't practically work out an equation that is dependant on square
area to determin pressure when the dimensions of this vehicle/the
impactor is unknown.  Now, something like this from space headed
towards the Earth would most likely heat and melt so fast that you
wouldn't know about any of the reaction between it and the air because,
it would burn up before it hit the ground.

I've been all over this site and have no idea what the area of the
impactor is but, when the details are all in it actually weighs more
than 370 Kilos or 816 pounds.  This one link gives me the most details
but, not those which are required to work out the equation.  I actually
found out that it disk shaped plate weighs that 816 pounds and the
instruments and guidance system are all in addition to that.  So, we
can count on a pressure that is well past 1 million Kilobars when you
consider the mass and inertia of a piece of foil weighing only a few
grams generating that kind of pressure in the Z Pinch machine.  The Z
Pinch machine is like a scaled down version of what it going to happen
in space.
http://deepimpact.umd.edu/tech/impactor.html

This much I can say, we as a race have never built a bomb so big.  The
blast could be comparable to 100s of 50 or 100 megaton bombs.  Another
part of the problem of depicting or calculating the extent of the
actual blast is that we don't know what the comet is made of nor if the
force of the blast will start a reaction that includes what we consider
non-nuclear matter, or lighter isotopes.  Deteruim is Heavy Hydrogen
but, it is still the lightest and smallest atom found.  So, somewhere
slightly about 1 million kilobars, almost anything can go nuclear just
as it would in a star.

Don't forget my insurance, while your on your way to the other side of
the planet.  Because, unless the scientists themselves admit this is
the case, no one is going to believe you or me.  What you do, or where
you plan to be when this happens is all up to you.  But, they are not
disclosing the exact time that this will occur, and I'm thinking that
between now and then there are so many potential variables that the
minute and the hour are still unknown but, probable.  It may not be
until June that figuring out where in the world you should be is even a
consideration.  If there is an EMP, the foot print dictates that there
will be a high voltage on the power lines and surge protectors may not
recognize that it isn't lightning and shut down all up and down the
power grid.  It is a day that I would say unplug your computer if you
want it to work on July 5th.  Transmitted radio waves, and EMP pulses
all have a different footprint based upon how they leave the source.
It's like looking at the design difference in a Tesla Coil verses a
60Hz line transformer.  Unless you spot a great big antenna somewhere,
and during solar flares the power lines/gas lines/pipelines can act as
large antenna.  If a nuclear bomb was detonated, the EMP approaches
like a expanding circle but, when an EMP is lit off miles away in space
it turns into a wall kinda like an electromagnetic tsunami.  Well, the
more power lines have magnetic lines passing through them at the same
time the higher the voltage.  At the two points of not knowing the
maximum pressure of impact, and not knowing what the comet is made of
makes an accurate prediction impossible beyond stating that there will
be a blast much bigger than that which Kinetic energy would displace.
4.8 Tons is way under estimating what the end result will be.  I
believe that they know this and the indicator here is simple go to this
link http://deepimpact.umd.edu/amateur/index.shtml and move your
pointer over this link  July 2005 on their page, mine doesn't work in
email.