| Article: 48184
From: [email protected] (John Roberts)
Newsgroups: sci.space
Subject: World Space Congress
Date: 6 Sep 92 22:10:05 GMT
Sender: [email protected]
Organization: National Institute of Standards and Technology
I hadn't been planning to go to the World Space Congress because I
couldn't get enough time off work to justify the $300 expense.
However, on Wednesday I found out that it was possible to register for
the exhibit hall only free of charge, so I visited it Thursday
evening. Very impressive - there were plenty of pieces of hardware and
models, including the NASP mockup (you can tell a lot about how
scramjets are supposed to work by looking at it), a Canadian RMS robot
arm (very large), an RL-10 engine (the type to be used on DCX), and so
on. There were also representatives from the many organizations
available to discuss their products and services (most of them were
very busy, and I didn't have time to talk to more than a few), and
videotapes. There were displays by US government organizations, US
companies, and foreign governments and companies. Foreign
participation was very high - perhaps about 50%. [Those of you who
have attended technical conferences in the past are probably aware
that there are often "local tours" available at extra cost as an
incentive to attendance. The WSC "local tours" included the Washington
area, but also Walt Disney World plus a cruise to the Bahamas,
white-water rafting and charter planes in Utah and Colorado, and an
Alaska cruise! I guess "local" is defined by by how far you've
traveled to get there. :-) ]
I got about 30 pounds of literature - I'll try to post interesting
items as I come across them. (It will probably be at least a month
before everything's organized and reviewed.)
It will be interesting when the big spenders who attended the lectures
get back and can post the details. I got about 12 hours of the NASA
Select coverage taped. I think many of the readers would be pleased by
the content of most of the speeches - they emphasized international
cooperation, and ways to make space exploration more cost effective,
such as reducing launch costs, small quick turnaround missions, and
trying new techniques. Administrator Goldin was among those who made
these comments.
John Roberts
[email protected]
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| Article: 48230
From: [email protected] (Andres C. Gaeris)
Newsgroups: sci.space
Subject: A personal report on the World Space Congress
Date: 8 Sep 92 21:45:16 GMT
Sender: [email protected]
Organization: UofR Laboratory for Laser Energetics
As a vacation I went to the World Space Congress both to
fulfill my longed desire of attending an IAF Congress and at the same
time knowing the Empire's capital.
Considering I payed only $25 for my registration at the WSC (I
am a graduate student at UoR), that Washington is the American city
that most looks like my old own city (Buenos Aires), the Smithsonian
Air & Space museum, the Space Exhibition at the Convention Center, the
Mars Rover rally and the receptions to the participants, this
vacations was not only enjoyable but a bargain!
In the minus side I was appalled by the poor scientific level
of the papers presented in the sessions I was most interested. As a
plasma physicist that got into this subject after reading an article
of Wolfgang Moeckel (_The Next 25 years of Planetary Exploration_, A&A
Nov71) on the future of physical propulsion as the only way of going
to deep space, I feel a profound interest on any non-chemical
propulsion method or technique (including Astrodynamics and space
power systems). Besides the dream of interstellar flight is one of my
most cherished ones so I went mainly to advanced propulsion sessions
of the IAF/WSC.
The scientific/technological quality of the papers seemed to
go inversely proportional to the distance the authors pretend to reach
or the power/energy levels they pretend to obtain. Now let me describe
what was going on in the main three sessions I attended.
The following text it is a very opinionated commentary of what
I saw at the WSC. Somebody could be offended/offuscated/upset about my
views, but I do not want to initiate any kind of flame war. So take it
or leave it, but please do not flame. Anyway, I am only a graduate
student and I do not pretend any expertise outside my field of study.
DISCLAIMER: THE OPINIONS, COMMENTARIES AND BAD JOKES APPEARING IN BOTH
THE PRECEDING AND FOLLOWING PARAGRAPHS ARE OF MY ENTIRE RESPONSIBILITY.
THE UNIVERSITY OF ROCHESTER, THE LABORATORY OF LASER ENERGETICS OR THE
DOE ARE NEITHER RELATED NOR AWARE OF THE CONTENTS OF THIS POSTING.
S.1 ADVANCED PROPULSION
There was very competent (and encouraging) papers describing current
research in plasma and ion thrusters from people at NASA Lewis, JPL,
Stuttgart and West Point. It seems that arc-jets and ion thrusters are
a sufficient mature technology to work but nobody wants to pay the
penalties of being the first non-experimental user of this gadgets.
Jordin Kare made a very exciting presentation about laser-heated
rockets for ground to orbit launch. I found Kare's work particularly
atractive due my current association to both very high power lasers
and laser-produced plasmas.
A. Bolonkin (from the research lab of the AES<- somebody knows what
AES stands for?) presented a paper on the new fashion on
sails-magnetic ones, but he was so boring (he read the paper) and the
trasparencies were so ininteligible that I suffered a momentaneous
brain disconnection and I cannot recall anything about his work except
the criticism done by Giovanni Vulpetti during the Q&A time about the
unworkability of magsails inside the Saturn's orbit due to the
formation of bow shocks between the solar wind and the sail's magnetic
field (I need some time to digest this comment, including to get a
copy(es) of the Zubrin/Andrews paper(s)). For the Argentinian slang
speakers in the net I cannot resist to add that Bolonkin's paper
honored the author's surname. 8-)
A pair of very enthusiastic researchers from Berkeley (Carpenter)
and McDD Space (Deveny) gave a really well researched talk on
magnetic-mirror fusion appl ied to propulsion with an eye to SEI
missions. Even when I am a little skeptic (mostly due to my plasma
physics professors telling me insistently that only tokamaks and
laser-ICF work) about the feasibility (even in the long-term) of this
kind of magnetic fusion configurations, it was noticeable the good
level of detail and effort put by the se guys, making this one of the
highlights of this session and the other physical propulsion presentations.
I cannot say the same about the closing paper of the session, mainly
because the fusion scheme elected to analyze was the plasma focus,
that had a moment of popularity as a would-be fusion reactor
configuration at the late 60's, due to its compacteness and high power
density, but it has been completely discredited among the plasma
community as a viable reactor since then because the inherent MHD
instabilities of the Z-pinch configuration in which it is based.
Without some experimental breaktrough giving some orders off magnitude
improvements on plasma stability, any plasma focus device is only a
cheap and compact gadget to study plasma physics and to generate high
intensity neutron pulses and not a serious way to fusion rockets.
F.1 EXPLORATION IN THE PLANETARY RANGE
F.2 EXPLORATION FROM PLANETARY TO COMETARY RANGES
Even with these titles it was pretty obvious from the names both of
the papers' contributors and the attendees to the sessions that these
were the usual IAA interstellar flight time slots. The most
speculative and risky papers appear here and I found myself very
dissapointed of the pre-screening of the presented papers. I believe
that there are enough and respected contributors to the field
(R.L.Forward, R.W.Bussard, G.Vulpetti, L.R.Shepherd, A.R.Martin among
others usually publishing at Acta Astronautica and JBIS) to do a
careful refereeing and selection of papers and avoid some of the
misleading and in one case completely absurd contributions to these
sesssions.
F.1
Matloff and Cassenti proposed a scheme to mine He3 using a pair of
magnetic lens es to focus the solar wind flow in a collector (other
new fashion among space industralization fans. Hey guys! How you
pretend a D-He3-based fusion economy when we are 10 years or more of
demonstrating D-T fusion breakeven scientifically and this milestone
probably will be done with reactors unworkable from the engineering
standpoint? Any attempt to predict what will go with fusion in the
next 50 years is mostly technology-fiction and even program insiders
-both magnetic and ICF- acknowledge that with the current levels of
funding and technology commercial fusion reactors in the near future
is some kind of rainbow chase). Again G.Vulpetti commented about the
infeasibility of this magsail methods (see Bolonkin's paragraph).
Cassenti emphasized the possibilities of using this design for a
toroidal uniform magnetic lens as part of a Bussard-ramjet scoop.
The dynamic duo of interestellar flight, Martin and Bond made a
competent but unimaginative presentation about coupling an ion
thruster currently manufactured ky UKAEA Culham (were both of them
work) to a state of the art but unbuilt SP-100/Topaz-like nuclear
reactor called Dragon, with interest to catch a contract for the JPL's
1000 AU mission. I found this paper a little too routine (not counting
on the advertisement content for the UKAEA line of products) for two
luminaries as Bond and Martin, who have me used to more spectacular
and always very good and comprehensive contributions.
A paper on a Martian Manned Excursion Module was given by R.J. Zhitz
of the Moscow Aviation Institute, but again the combination of
monotonous reading with poor transparencies send my brain to other
realms of the mind and my body to look for a cup of coffee, so I do
not have any opinion on this paper, except that Russian (and other
East-Europeans) must improve their presentation skills if they want to
reach their audiences.
P. A. Hansson made an interesting and audacious presentation of the role
of miniaturization and nanotechnology on the future advance of space
instrumentation and probe design, but I am not knowledgeable in these
matters so my opinion is as good a anybody else's.
Finally for the F.1 session, V.J.Modi gave a very heavyweight talk on
attitude control and propulsion of space vehicles using solar radiation
pressure. Pretty interesting and really good technical stuff.
F.2
I lost the first one on Artificial jets as propulsion of cometary riders
because I was late. I catch a little of the last moments of it and the
Q&A part, but I do not have any elements for a responsible comment.
The Zubrin paper was superb from the presentation point of view (this
guy really knows how to catch the attention of his audience) but I
found it flawed in approach. It discuss the use of unknown ultra-dense
stellar objects (white/brown/black dwarves, neutron stars, black
holes) in the near-solar neighborhood for perigee-kick gravity assists
for interstellar missions. The paper is interesting, the ideas are
relevant but the methods are poor. Calculating orbits near high
gravitational fields using classical mechanics or special relativity
is at best inaccurate and as the last case (black hole) analyzed by
Zubrin can be completely wrong (v-infinity speeds greater than c are
predicted for some orbits!). As my GTR knowledge is today non-existant
(but it will be some at the end of this semester) and besides I could
not afford a copy of the paper, I can not be more explicit about where
is the mistake in Zubrin's calculation, but obviously he is using the
wrong model for this problem.
H. D. Froning spoke about the neccesity of launching an Interstellar
Exploration Initiative, now! ;-) Any further comment from me would be
insulting for the author of otherwise a very enjoyable presentation
that esentially was not more than an exercise of wishful thinking (but
anytime some guy come speaking about field propulsion, hyperspaces and
quantum vacuum energy ramjets and the necessitiy of funding research
of this my stomach revolves, I get a cold fever and I must see the
current NSF/DOE/NASA budget to recover myself with a reality shock).
I am being insulting now because I felt insulted when hearing this
nonsense. C. Poher from CNES/Aerospatiale at Cannes-La-Bocca, France
(probably affected for the excess of sunlight at the Cote-Azur)
presented a paper (well...) with the title _Universons, a possible key
to interstellar exploration_ This guy invented a theory of gravitation
of his own, which contradicts any current experimental evidence from
both GTR and Quantum Mechanics. Again G.Vulpetti came to the rescue
and clobbered the guy with a set of very good questions and
counterexamples. It is a shame that this kind of crap appears in this
conference, because my colleagues in Physics and Astronomy use this
comtemptible examples of crankpottery to discredite the scientific
value of these sessions in particular and of the IAF Congresses in
general. Does somebody suggest a way to comunicate to the IAF or IAA
committees relevant to these sessions the damage that papers like this
one do to the credibility of these organizations?
After that A. Ewing refreshed the air with a short nice competent work
on solar sail parametrization.
Finally G.Vulpetti introduced the concept of staged propulsion (that
is a generalization of the usual fuel staging), and then provided us
with a bunch of colorful (literally) examples of missions using
combinations of solar sails/NEP for missions to the heliopause and
beyond. Really good stuff, with good scientific and technical fundaments.
At the end of each presentation there was a Q&A period, usually used
by L.R.Sheperd to do some interesting and appropiate comment, by
Vulpetti to argue (with great authority) about some weak point of the
past paper and for a annoying crank to illuminate us with some
irrelevant and inane comment of his own.
One thing I notice after enduring both F.1 and F.2 in their entire
duration was that the audience was thinning more and more with time,
going from ~25 people at the beginning to no more than a dozen at the
end. Was the audience voting with their feet?
I attended only two other IAF sessions(Nuclear power applications and
space in cinema and photography) but I would not comment on them.
As friend of one of the leading SETI researchers in Argentina I was in
some way an informal member of the Argentinian delegation to the SETI
session organized by the IAA/COSPAR/IAF/NASA/AIAA. Of course I was
introduced to all the SETI-set (and I got a photograph with George
Mueller, who opened the session, a thing that had me smiling two days
but considered irrelevant to my astronomer friends) and I was witness
of a lot of the behind the curtains talks. The feeling I got from all
this is that now SETI is fashionable for some sectors of the
radioastronomical community and a lot of guys that five years ago
would not have paid any attention to the search programs now are
trying to jump into the SETI bandwagon (and catch the research
grants!). Considering that the field is mostly hot air (and it
reflects in the low quality of the papers presented -again the French
are talking nonsense, introducing numerology into a fact-poor subject)
I cannot understand the hype that SETI produces, unless you want to
see it as an exercise on publicity and marketing for certain
brands/names of this self-advertised community of scientists.
You will be asking what I found positive about WSC?
- The International Space Exhibition
- The talks with the participants outside the sessions.
- Washington DC
- The Smithsonian museums
- The atmosphere of comradeship and collaboration for the most exciting
goal you can imagine: THE CONQUEST OF SPACE.
Even with the shortcomings about the sessions contents I found myself
mesmerized with the WSC and I will attend again anytime this events
repeat near my workplace or I could afford to go.
Andres C. Gaeris
[email protected]
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