Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_3/V13_368.TXT

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Subject: SPACE Digest V13 #368

SPACE Digest                                     Volume 13 : Issue 368

Today's Topics:
    Re: One Small Step for a Space Activist...  Vol 2 No 4
                 Face on Mars
              Re: More cost/lb. follies
          Re: Commercial Space News (1 of 5)
             Re: Nuclear Rockets
          GEOMAGNETIC STORM UPDATE - STORM HAS ENDED
         Re: Commercial Space news (5 of 12)
             space news from Feb 18 AW&ST
        Re: Underground Nuclear Test in Nevada

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription requests,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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

Date: 4 Apr 91 01:18:38 GMT
From: unisoft!fai!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: One Small Step for a Space Activist...  Vol 2 No 4

In article <[e-mail]> [e-mail] (Charles Frank Radley) writes:

>I am puzzled about complaints that nobody is proposing
>"real" hardware and schedules for SEI.    The following
>paragraph answers the question - everybody has been holding off
>waiting for the synthesis report.......

Nobody seriously expects a Manned Mars Mission to be funded at anything
within an order of magnitude of the present pricetag.  I know if
I seriously expected it, I would be screaming bloody murder over
such a colossal waste of resources.  Meanwhile, some interesting technology
many come out of SEI, if they can work some prototypes in between all the
papers being passed back and forth.  So for now, a research-oriented
SEI is quite worthwhile.


--
Nick Szabo            [e-mail]
"If you want oil, drill lots of wells" -- J. Paul Getty
The above opinions are my own and not related to those of any
organization I may be affiliated with.

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

Date: Fri, 5 Apr 91 17:31 GMT
From: AMON <[e-mail]>
Subject: Face on Mars


I'm not going to say yea or nay to whether it is or isn't. But some incorrect
statements have been made.

First, there are TWO images that show it, in different lighting and different
angles. 35A72 and 70A13.

The image processing work done on these was done from raw data, and I have seen
stunning 3D reconstructions. The "face" and 5 sides pyramid do indeed "look"
like the names suggest. I will not claim they are or aren't. I would very
much love to see more photos of this area.

The Hoagland book is a bit extreme and mines these two photos for several
hundred pages of text. It tries to create a civilization out of them and some
of the resampling techniques used in the image analysis may have led to
artifacts, in particular the "grid" structure in one enhanced image.

Regardless of that, I'm impressed by the visual impact of the images. They most
likely aren't anything by rocks of interesting shape, like the Kermit the frog
look alike someone mentioned a few years ago.

ANyone who is interested should dig in the Space Digest archive for the
previous go around on this between myself, Phil Karn and others, circ 1988 or
so.
                        Ad Astra,
                        Dale Amon

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

Date: 27 Mar 91 18:10:51 GMT
From: usc!hacgate!ashtate!dbase![e-mail]  (Michael Wallis)
Subject: Re: More cost/lb. follies

[e-mail] (Nick Szabo) writes:

>* We need 4 orders of magnitude drop from today's costs for space
>  colonization to be affordable.
>* Chemical rockets can provide less than an order of magnitude drop
>  between now and the end of the 21st century

>On the first point, divide the cost of a hypothetical Shuttle/OTV
>trip to L-5 ($40 million/person) with round trip first-class from
>Tokyo to New York ($2,000/person) to get 4 orders of magnitude.

I'm intrigued about where you got the $40 million/person figure. I
thought the going price was about $12 million (nearly half an order of
magnitude drop right there). And I think an analogy to a $14,000 around
the world cruise would be more appropriate. (BTW, New York-Tokyo First
Class on United is $2766 ONE WAY as of 27 March 91.)

>Plug in more precise numbers if you like, but all of these results
>fall within an order of magnitude of current launch costs.  A safe
>conclusion is that costs/lb. will not drop by more than an order of
>magnitude.  Even a factor of 5 is improbable: I will lay bets with any
>takers that unsubsidized chem rocket costs will never drop below $1,000/lb.
>(long before 2100 they will be replaced by something better).

Well ... I think it's a wonderful proof for the need for single stage
reusable vehicles. We can do about 20% of current costs ($1000/lb) now
and can improve that significantly with a little tinkering.

I also question your assumption that 4 orders of magnitude (50
cents/lb!) are needed to open space. One order of magnitude (to $500/lb)
would be sufficient to start the development of space and that's
certainly reachable this decade. Two orders (to $50/lb) may be
achievable early next decade by volume and mass production alone. I
agree that the third order of magnitude (to $5/lb) is likely beyond the
reach of chemical reactions, but I don't see you proposing any
alternative.

>Until we develop a method much better than chemical rockets, we must
>be damned smart about what we launch, and search for all opportunities
>to let the solar system do the work for us.

I agree entirely, but let us not feel we must rely on NASA and the aging
Shuttle fleet as the backbone of space exploration. For the price of one
shuttle launch (~ $500 million) we could (read I can) develop far better
reusable vehicles and open the doorway to space development.


-------------------------------------------------------------------------------
Michael Wallis                          INTERNET:       [e-mail]
Computer Consultant                     CI$:            75470,1264
Santa Clara, CA   USA                   bix:            mwallis
                   "Frankly, I'd rather be building rockets!"
              #include "standard disclaimer"
--
-------------------------------------------------------------------------------
Michael Wallis                          INTERNET:       [e-mail]
Computer Consultant                     CI$:            75470,1264
Santa Clara, CA   USA                   bix:            mwallis

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

Date: 4 Apr 91 17:03:06 GMT
From: usc!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!emory!wa4mei!ke4zv![e-mail]  (Gary Coffman)
Subject: Re: Commercial Space News (1 of 5)

In article <[e-mail]> [e-mail] (Wales Larrison) writes:
>------------------------------------------------------------------
>OSC REVEALS PROTOTYPE TO COMMERCIAL COMMUNICATIONS SATELLITE
>   Orbital Sciences Corp (OSC) recently showed off its experimental
>precursor of a small, low-orbiting store/dump communications
>satellite.  As described by OSC, the ORBCOMM-X satellite is about 35
>lbs in weight and use about 8 watts of power.  It is planned for
>launch as a "hitchhiker" smallsat payload on an upcoming Ariane-4
>launch in May.  The Ariane will deploy the ORBCOMM-X satellite into
>a polar orbit of about 480 miles altitude while inserting another
>polar orbiting satellite.  The ORBCOMM-X satellite will demonstrate
>the capability to receive a communications from its ground station
>in Virginia, store it, and then retransmit it to the ground on its
>next pass.  This will demonstrate prototype operations for a
>proposed network of 20 similar satellites to provide continuous data
>communications, messaging, and position determination to customers
>worldwide.

The amateur radio satellites called PACSAT are on orbit and operating
using this technology. AMSAT, the amateur radio satellite organization,
started the craze for light satellites by demonstrating the practicallity
of small, light, spacecraft for remote communications, termed Microsats.
In this series are store and forward digital communications satellites,
a satellite with an earth observing camera, and a satellite with digitized
voice capability. All are built using the same physical and electrical
buss with stackable, interchangeable modules. This was all accomplished
with volunteer labor and private funds. They are real, on orbit, and
operating *today*. Ground terminals can be carried in a briefcase.
Unless OSC has tapped into this base of knowledge and experience,
they are re-inventing the wheel with their ORBCOMM-X program.

Gary KE4ZV

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

Date: 5 Apr 91 22:39:10 GMT
From: usc!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Nuclear Rockets

In article <[e-mail]> [e-mail] (Frank Hage) writes:
>    If a nuclear rocket develops thrust by vaporizing liquid hydrogen
>passing over (through?) the reactor core, and the hydrogen acts
>as the coolant, what keeps the reactor from melting "before ignition"
>and after the LH fuel has run out?

As with more conventional reactors, there are control rods that have a
fair bit of say in how much heat is generated.  Before startup, the rods
are in and the reactor is quiet.  At startup, they are withdrawn and
things heat up.  At shutdown, they are moved back in and things quiet
down... almost.  After the reactor has run for a while, there is some
residual heat generated by fission products that cannot be shut off,
and dissipating this heat somehow is an important design constraint.
--
"The stories one hears about putting up | Henry Spencer @ U of Toronto Zoology
SunOS 4.1.1 are all true."  -D. Harrison|  [e-mail]  utzoo!henry

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

Date: Fri, 5 Apr 91 15:28:37 MST
From: oler <@BITNET.CC.CMU.EDU:[e-mail]> (CARY OLER)
Subject: GEOMAGNETIC STORM UPDATE - STORM HAS ENDED
X-St-Vmsmail-To: st%"[e-mail]"

                       /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\

                            GEOMAGNETIC STORM UPDATE

                            Storm Alert Cancellation

                       /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\

                               22:00 UT, 05 April

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


STORM UPDATE INFORMATION:

     The geomagnetic storm has ended.  Activity has returned to generally
unsettled conditions.  The period of most intense activity occurred within
the first few hours of the interplanetary shock.  Minor storming was observed
for about six to nine hours following the SSC.  Most of the magnetic storming
was of low intensity, although higher latitudes did experience periods of
major storming.

     Auroral activity was visible as far south as about 45 degrees north
latitude.  Generally moderate activity was observed over the northerly middle
latitudes, while high latitudes experienced periods of high auroral activity.

     HF propagation conditions were not seriously affected by this minor
storm.  Higher latitudes experience the worst conditions, with significant
flutter fading and higher than normal levels of absorption and noise.
Conditions are returning to normal.

No warnings are in progress at the present time.

The following alerts remain IN PROGRESS:

   - SATELLITE PROTON EVENT ALERT


                       /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\

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

Date: 6 Apr 91 01:27:45 GMT
From: hub.ucsb.edu!ucsbuxa![e-mail]  (Charles Frank Radley)
Subject: Re: Commercial Space news (5 of 12)



Oh yes, when the ELV companies say they are not subsidized by the
US govt, ask who owns their tooling.......
   A paraphrasing of Art Dula quoted in the LA Times.
:

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

Date: 5 Apr 91 08:07:09 GMT
From: dog.ee.lbl.gov!hellgate.utah.edu!caen!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: space news from Feb 18 AW&ST

[March issue of Spaceflight mentions that astronaut William F. Fisher has
left NASA to return to medical practice.  No big surprise, on thinking
about it:  he was co-chair of the group that reported the bad news about
EVA requirements for Fred, which probably killed his chances of future
flight assignments.]

Editorial urging that SDIO get sensible about tactical-missile defence,
dumping the silliness of applying Brilliant Pebbles to every problem and
concentrating on urgent near-term availability of competent ground-based
interceptors with better coverage than Patriot.

Aerojet gets modest research contract from Army Strategic Defense to build
a 33klb rocket engine using gel propellants, in the hopes that gels will
give safer field handling than liquids while retaining stop-start and
throttling capability.

Bush signs new commercial space policy guidelines, stressing government
purchase of commercial products and services when possible.

OMB orders independent engineering review of NASA's EOS plan, reportedly
to look particularly at the wisdom of large multi-sensor platforms.

SDI estimates worldwide limited-attack protection system at $41G.  The
design target is complete destruction of a 200-warhead attack, including
coverage for US territories, allies, and military forces in the field.
Third-world tactical missiles and the possibility of accidental and
unauthorized attacks from a politically-unstable Soviet Union are the
major threats seen.  The only real technical surprise is a willingness
to consider shipboard and airborne launch platforms.

Patriot succeeds as tactical missile interceptor in the Gulf, with a
100% interception rate for Scuds engaged over Saudi Arabia in the first
three weeks of Desert Storm.  (Some Scuds were not engaged because they
were headed for water or open desert.)

Study indicates that Navstar is not suitable for use by itself as a
precision approach system for aircraft blind landings, although it could
be very useful in combination with the new ground-based Microwave Landing
System [which is somewhat controversial due to conversion costs from the
older ILS now in use].  Various improved forms of Navstar, e.g. differential
systems and phase-tracking receivers, could achieve "Category 1" accuracy,
or nearly, but not "Category 3" [the really heavy-weather blind-landing
standard].  The fundamental problem is that Cat 3 requires a maximum 2s
delay between a system failure and a warning to aircraft on final approach,
and even an extensive ground-receiver network with a new data link to the
aircraft would have trouble meeting this.  A further complication is that
a satellite failure that kills Cat 3 capability at one airport will affect
other airports in the area too.  Finally, the non-military part of
Navstar is not really accurate enough for Cat 3 even with differential
methods, due to substantial altitude errors.  It could, however, give
much better accuracy than MLS for the early phases of landings, plus
better coverage of possible abort trajectories in case of trouble,
while leaving MLS (which gets more accurate as range closes) to handle
final approach.

Soviets reveal details of their N1 booster, meant as their Saturn V
equivalent for manned lunar missions.  The N1 used massive clustering
of engines, and reliability problems in the 30 (!) first-stage engines
were its Achilles' Heel.  Early reports suggesting that the N1 would
carry up the lunar spacecraft and rocket stages while a Soyuz launch
carried the crew up appear to have been incorrect; it now appears that
a single N1 launch would do the whole job.  The first three stages
would put a Soyuz, a lander, and three more rocket stages into Earth
orbit.  The fourth stage would boost the rest toward the Moon.  The
fifth would brake the rest into lunar orbit, and then do most of the
deceleration of the lander, being jettisoned shortly before landing
to crash on the Moon.  [This "lunar crasher" approach was seriously
considered for Apollo for a while.]  The lander engine would then
complete the landing, and later be used to boost back to lunar orbit.
Finally, the sixth stage would boost the Soyuz back toward Earth.
The total crew would be two, with only one descending to the lunar
surface, and crew transfer between Soyuz and lander would be by EVA.
[Actually, various elements of this resemble rejected alternatives
in the US program; similar problems, similar solutions.]
--
"The stories one hears about putting up | Henry Spencer @ U of Toronto Zoology
SunOS 4.1.1 are all true."  -D. Harrison|  [e-mail]  utzoo!henry

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

Date: 5 Apr 91 20:15:54 GMT
From: snorkelwacker.mit.edu!spool.mu.edu!cs.umn.edu!ariel.unm.edu!triton.unm.edu![e-mail]  (John Prentice)
Subject: Re: Underground Nuclear Test in Nevada

In article <[e-mail]> [e-mail] (MURTY  Hema Sandhyarani) writes:
>
>    Yesterday there was another underground nuclear test in
>    Nevada.  Why are we allowing this to continue?
>
>    I am sure that if all the readers of sci.space got
>    together and denounces such tests by countries of
>    the world, they would have to stop.
>

Are you serious?  Somehow I don't think the readers of sci.space have
that kind of political clout!

>
>    And, yes, I would like to hear arguments that any
>    might have in favor of these tests.  What do they
>    accomplish in terms of science?  They seem more
>    like muscle-flexing to me.
>

Why should they have ANY scientific value?  The issue is not science,
it is military.  There are lots of reasons for testing weapons, not
the least of which is verifying that the stockpile is still working.
I am not advocating nuclear testing or denouncing it here, but your
comment suggests that there is no plausible reason to do it
and that is nonsense.  That the U.S. and Soviets might be able to
cease and not destabilize their deterrents, perhaps so.  But the very
fact that they are worried about this possiblity suggests that there
are very real military concerns which nuclear testing addresses.

I will say this.  The arguments against nuclear weapons and weapons
testing do not move me a great deal.  I would be more impressed by
attempts to eliminate world strife and the root causes of conflict
than attempts to control the means by which nations wage war.  I
am also struck by the fact that for all the noise made over this
issue in recent years, the really terrifying weapons are conventional,
not nuclear.  The chances of a nuclear war between the superpowers
is almost nil and the consequences of a third world nation using a nuclear
weapon, while serious, are not going to be affected in the least by
what the superpowers do to limit or control their arsenals.  On the
other hand, the chances of conventional war in the world are obviously
rather high.  If one wants to make a difference in arms control, you would
do better to address conventional weapons rather than getting
wrapped up over exotic and unlikely ones.

John
--
John K. Prentice    [e-mail] (Internet)
Dept. of Physics and Astronomy, University of New Mexico, Albuquerque, NM, USA
Computational Physics Group, Amparo Corporation, Albuquerque, NM, USA

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

End of SPACE Digest V13 #368
*******************