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Date: Sun, 12 May 91 01:55:59 -0400 (EDT)
Subject: SPACE Digest V13 #530

SPACE Digest                                     Volume 13 : Issue 530

Today's Topics:
			 Re: NASP and Aurora
		       Re: Terraforming Venus?

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Date: 7 May 91 23:02:50 GMT
From: littlei!intelhf!ichips!news@uunet.uu.net  (Larry Smith)
Subject: Re: NASP and Aurora


Craig Cole writes:
>Any chance anyone out there working on the NASP can post regular updates
>on progress with the NASP?
>
>Scientific/Engineering hurdles & successes, budget concerns, progress
>on the prototype when its construction is started...
>
>I for one am very interested, and can't seem to find enough about
>it in magazines, etc. I bet a lot of others are interested too.

That's good to hear. I know of people working on a book about
NASP (I've even been asked to help), however they are having trouble
getting a publisher to sign up.

A lot of the publishers are waiting for 1993, when the decision
on building 2 vehicles will be made. I believe this is a mistake.

Even now, there is a very interesting story here because of the
history of this type of aircraft. 

For example, there was a project called ASP (AeroSpace Plane) back in 
the 60's, and there have been many government and aerospace company 
funded looks into this type of aircraft, or its propuslion systems, 
ever since the early 50's. There is a lot of information that is
now declassified and available.

This information provides a good background in which to frame the
current program.

Classic Motorbooks is the only publisher interested in a NASP book now
and Bill Sweetman is aledgedly interested, although I have no confirmation
of this. We are checking on this now.

Michael Kent writes:
>Probably not a good idea.  Most of NASP is classified.  What isn't will prob-
>ably be in Henry Spencer's AvWeek summaries.  For a peek at the program, check
>out the 29 Oct 90 issue of Aviation Week.

A lot of the hypersonic technology that will be used to design NASP is NOT
classified. In other words the basics are not classified. The advanced 
application of that technology IS mostly classified, but one can certainly
go a long way at educating the public about these systems by using the
basics.

You can indicate where the hard parts of the design are (all of it), and
what the characteristics of the solutions are. 

Also, some of the foreign teams are talking about their successes, and it
is possible to learn a lot from that. You can also talk about some of the
unclassified university based research, that the NASP national team may
never use now, but nonetheless, is very interesting.

You can also infer things about NDVs (NASP Derived Vehicles) which
would be highly classified (at least the military ones).

Right now Craig Cole is right. The public has only been given very simplistic
information about this program.

I don't think that the NASP program is against any positive pro-NASP 
information getting out to the general public. These types of aircraft, 
to me, are THE most exciting aircraft ever! Also, this program, even in
flight test, will be a technology development program. I think the public
would easily understand that if they understood the basics.

Allen W. Sherzer writes:
>Well, I don't work on it but one of my congressional sources is very
>interested in it.  I'll ask him now and then and post what I can.
>
>One very interesting thing has happened recently on the political front.
>In recent testimony military whitnesses have been very enthusiastic about
>NASP. This is a far cry from past years when they saw no need for it. They
>now see lost of missions for it now and are interested in funding it. This
>is a far cry from years past where they zeroed out their part of the funding.
>
>If this continues, the large hurdle which NASP needs to cross to get a
>vehicle built will be a lot easier.

See Aurora comment below.

Mary Shafer writes:
>I don't want to discourage your interest, but you should be prepared
>for a lack of real information.

Well if your talking about, for example,  the real shape of the inlet on the
underside I agree, we will have to wait for rollout in 1996 or whenever.

However if you are telling me that I just spent $350 to have Dr. Kevin Bowcutt,
head of the NASP nozzle design effort, lie to me and give me and other engineers,
disinformation on hypersonic aerodynamics, I will be ticked!! Dr. Bowcutt
used an airframe design very similar to the current team NASP design in his lecture
on hypersonic vehicle design. He even pointed that out in his lecture.
He presented a design methodology for hypersonic accelerators (aircraft).

Now I'm not expecting that Dr. Bowcutt told us everything, but the points he did
make were VERY interesting, and I think that a lot of people would be very
interested. 

I was even saying to myself during the class, I don't believe this stuff
is unclassified! Geee, I wonder what the classified stuff is!!

So I guess I'm saying, hey, there is some really great unclassified stuff
on this program out there!

Doug Mohney writes:
>NASP is quite probably liberally building on "Aurora" and other black
>hypersonic projects. 

Phil Fraering writes:
>What if it isn't? I get the strong feeling that a lot of duplication
>of effort is going on.

Yes, this possibility was brought out in a AW&ST story back in Dec, 89.

Many NASP people claim no knowledge of what we call Aurora. They even claim
that after the AW&ST articles, they tried to find out, with no luck.
The Air Force claims no knowledge of it either.

As Allen W. Sherzer wrote earlier, the Air Force's sudden appreciation of
the program is interesting (actually they have always been interested,
they were just never officially interested). I have a recent technical document
(not with me) written by an Air Force officer on NASP stability and control.

He says something very interesting at the end of the document. He says that
hypersonic cruisers are already possible. NASP's goal is to develop
hypersonic accelerator technology. 

Maybe in that context, the Air Force can now feel good that there isn't a
duplication of effort going on.

In other words, Aurora would provide hypersonic cruiser technology, and
NASP would provide hypersonic accelerator (SSTO) technology.

Ever wonder why the NASP team design isn't a waverider type design? That's
why. For hypersonic accelerators, you don't need the high hypersonic L/D
that you need on a cruiser. 

Waveriders currently have the highest known hypersonic L/D's (on-design).
There is controversy about their off-design capabilities. That is still being
researched. 

It is not necessarily true though that an existing hypersonic cruiser would
be a waverider.

Larry Smith
larry@ichips.intel.com

------------------------------

Date: 8 May 91 16:01:01 GMT
From: stanford.edu!agate!tornado.Berkeley.EDU!gunter@decwrl.dec.com  (Michial Gunter)
Subject: Re: Terraforming Venus?

Disclaimer:  I'm temporalily using my friend's account.  Please do not reply
to this article by mail.

In article <11990@jarthur.Claremont.EDU> jhuyghe@jarthur.Claremont.EDU (Julien David Huyghe) writes:
>Could a couple of HUGE fusion bombs (in the 1000 gigaton range) blast away
>99% of Venus' atmosphere, leaving us with a manageable situation? Or is
>it just too much trouble launching a couple of aircraft-carrier-sized
>bombs?

	Many suggest using thermonuclear explosion for terraforming
for obvious reason:  Enomous energy required for terraforming.  Let me
discuss this issue in detail.

	I'm not sure if H-bomb has enough energy and more importantly,
controllability to get rid of enough CO2-rich atmosphere.  But this is
not the only thing we need enomous energy.

	Do you remember that Venus has very long sidereal period (i.e.
day), which is actually longer than the rotation period w/ respect to
the Sun (i.e. year).  This causes a lot of problem in its atmosphere.
	Longer day means more temperature difference between day and
night.  And/Or stronger wind from day resion to night resion. To
control the Venusian climete, we have to do something to it.
	We can either adapt Venus to us or vise versa.  1st solution
doesn't deserve the name of terraforming:  We are to adapt the
environment to us, not us to the environment.
	So we have to increase the rotational period of venus.  And
window-of-an-DA calculation (90's way of saying
"back-of-the-enverope") says we just don't have enough energy at our
disposal.

	Venus has mass of 4.87e24 kg.  And its radius (equatorial) is
6052km.  Thus the moment of inertia, provided its mass is distributed
evenly is: 
	I = 2/5 MR^2 = 7.21e+37 kgm^2.
	Thus in order to accerarate its day to one earth sidereal day
(= 23h 56m 04s), Energy it takes would be:
	K = 1/2 Iw^2 (sorry no small omega in ascii)
	  =  1.92e+29 kgm^2s^-2 (J).
	In mass, divide it with c^2 and we get 2.13e+12kg!

	Of course this is just a WOADA calculation.  But I think this
figure is correct by magnitude.  We don't know how fast is fast enough
(Slower the better, of course:  By factor of the square of its angular
velocity).  But we don't have 1 trillion tons of antimatter or
alternate energy source, much less how to apply that much energy
properly.  I don't know how much energy 1 megaton of TNT releases
(Anyone?)  But you got the point.  In this respect, Mars is much
easier to terraform for it already has fast enough day (almost 1 Earth
Day).

	Probably it takes "Vacuum Energy Drive" used in the A.C.
Clarke's great novel "The Song of Distant Earth".  In that novel it
first decomposes polar cap of Sagan 2--planet the last people of Earth abord
Magellan would colonize--to oxygen and hydrogen using its infinite
energy from the "Quantum Drive" (Alias "Vacuum Energy Drive").  Then
Magellan lands on Sagan 2 and with its omnipotent Quantum Drive to
push Sagan 2 inward to its sun up to the habitable zone.  With
something like Quantum Drive terraforming Venus would be as easy as,
say, constructing English Channel Tunnel.  But we don't even have
fusion for terraformer's sake!!!

	From economical point of view, terraforming in general,
perticularily venus, takes too much work for too little gain compared
to such alternatives as Space Colony--Even O'nell's Island 3--A 6km in
diameter and 32km long--is just a Barby's house compared to
terraforming any planet.
	I can bet (even though I know I can't live long enough to
collect my wager) all my fortune and organ that terraforming will not
come before we move most of us humankind up to Space Colony.  And with
Colony I wounder if our future government has any need for terraformed
planets--Study alone would cost many magitudes more than the Gloss
Global Product.

	Still, I dream of terraforming. Especially Venus.  Venus is
just so close to Earth.  Venus never made children like its sister
Gaia did.  Isn't it really impossible to "convince" her to adopt some
of her sister's children which are us?
	I am sorry for myself being born couple of millenia too
early--late enough to know of terraforming, too early to see it come
true.  It's not life that sucks.  Gravity sucks life.

------------------------------

End of SPACE Digest V13 #530
*******************