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Subject: SPACE Digest V13 #478

SPACE Digest                                     Volume 13 : Issue 478

Today's Topics:
                   Re: NASP
               Re: Saturn V and the ALS
        Re: Alexander Abian wants to blow up the moon?
             Re: Saturn V vs. ALS
        Re: Alexander Abian wants to blow up the moon?
             Re: Galileo Solution
              Re: Galileo works?
             The state of Galileo

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: 28 Apr 91 06:43:51 GMT
From: swrinde!zaphod.mps.ohio-state.edu!rpi![e-mail]  (Michael V. Kent)
Subject: Re: NASP

In article <[e-mail]> [e-mail] 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.

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.

Michael Kent                                             [e-mail]

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

Date: 27 Apr 91 20:11:41 GMT
From: agate!bionet!uwm.edu!rpi!zaphod.mps.ohio-state.edu!mips!spool.mu.edu!cs.umn.edu!kksys!edgar!saylor![e-mail]  (Jim Anderson)
Subject: Re: Saturn V and the ALS

After spending an hour or so trying to catch up on news, this discussion
on the Saturn V and the ALS brings two questions to mind:

1.  Bunches of figures have been brought up regarding cost per pound to
    orbit.  What was Saturn V's cost to orbit?

2.  The talk about increasing launches by an order of magnitude or so
    with use of a 'rebuilt Saturn V/VI/ALS/whatever' brings to mind
    the discussion that keeps cropping up (that I haven't seen for
    a while though) about space debris.  Wasn't the Saturn V putting
    a bunch of garbage into orbit?  And wouldn't any serious usage
    of a heavy lift launcher produce that much more space garbage?
    Would this garbage start affecting launch successes? (If a payload
    isn't usable once it gets on station, and stays usage, I don't
    consider it a successful payload.
--
Jim Anderson            [phone]
Saylors Software First        [e-mail] or [e-mail]
6532 Edenvale Blvd        Lucifer designed MS-DOS to try men's souls.
Eden Prairie, MN 55346

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

Date: 27 Apr 91 08:40:39 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!caen!news.cs.indiana.edu!ariel.unm.edu!hydra.unm.edu![e-mail]  (Charles J. DiBella)
Subject: Re: Alexander Abian wants to blow up the moon?


--
   ========================================================================
     Charles J. DiBella                               [e-mail]
     University  of  New Mexico,  Albuquerque         Home [phone]
   ========================================================================

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

Date: 29 Apr 91 04:33:35 GMT
From: agate!lightning.Berkeley.EDU![e-mail]  (Frank Crary)
Subject: Re: Saturn V vs. ALS

Frank Crary (me):
>>However US companies CAN make long term investments. Orbital Sciences
>>Corporation has yet to make a cent on the Pegasus launcher... Is this not
>>a long term investment in space infrastructure by a US company, wh
>>thinks there is a market?
Henry Spencer:
>It is.  Now for the hard part of the assignment:  name three more such
>investments, to justify the plural in "companies".  The OSC/Hercules
>Pegasus effort is a rare exception, not the rule.

While OSC is the most succesfull example, they are not the only one:

The following small launch vehicles are being designed by US firms, without
government support.

Industrial Launch Vehicle, by American Rocket Company. This project also
   is doing technology as well as vehicle development since the ILV will
   use hybred sloid/liquid oxygen rockets.

Conestoga Launch Vehicle, by Space Services, Inc.

Astra B, by E Prime Aerospace Corp.

While these rockets have yet to fly, they are ungoing projects funded by
american inversers, rather than a major government.

OSC is also, by the way, continuing to develop upper stages (on its own hook)
including, I believe, an electronic propulsion (Ion drive) upper stage.

                       Frank Crary
                       UC Berkeley

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Date: 28 Apr 91 06:22:29 GMT
From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!mips!spool.mu.edu!uwm.edu!ux1.cso.uiuc.edu!news.iastate.edu!vaxf.iastate.edu![e-mail]
Subject: Re: Alexander Abian wants to blow up the moon?


    I've read about Dr. Abian's ideas about blowing up the moon a couple
times now in the Iowa State Daily.  One thing that REALLY makes me wonder
about the guy is this:  Does he expect the moon to simply disintegrate
cleanly in front of our eyes, provided all of us on Earth decided to blow
it up (yeah right) !?  It would seem to me that anyone who uses any kind
of common sense would happen to realize that there will be moon debris
everywhere, including bombarding the Earth, perhaps even killing off
all life on the planet via a massive impact of a relatively "small" piece.

    Perhaps I should visit Dr. Abian's office some day and ask him about
what he thinks of that.....Hmmm.....We'll see about that.  (He seems
QUITE gung-ho in his opinions.)

    Many people theorize that an asteroid struck the earth millions of
years ago, causing mass extinction.  Most asteroids are quite tiny compared
to the moon, and when you consider that such a seemingly small piece of
rock can do so much damage to a planet, it really makes you think.
(Especially since the Earth very recently almost had a date with an astroid
that was about 17th magnitude, and just over 100,000 miles away from us
(half the distance from here to the moon) )

    I can see that I'm starting to ramble so I'll quit while I
am ahead (?).

                        Tony A. Landin ([e-mail])

                        -- Iowa State student

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

Date: 28 Apr 91 23:30:54 GMT
From: rochester![e-mail]  (Paul Dietz)
Subject: Re: Galileo Solution

In article <[e-mail]> [e-mail] (Matthew DeLuca) writes:

>I dunno about this one.  Getting a look at the atmospheric composition
>of Jupiter from the 'top' of the atmosphere on down to where the probe
>stops transmitting would seem (to me) to be worth a *lot* more than
>a few extra asteroid encounters, especially considering that the original
>encounters can still be done.  Not to mention, the extra detail (as compared
>to Voyager) we can get on the moons of Jupiter is worth a lot, especially
>for Io and Europa.  Dropping all this for a few measly asteroids seems to
>be a waste.

I was not clear.  This change in plans assumes the relay doesn't get
built, so that most of the science at Jupiter (all of it?) can't get
done.  I was assuming the relay would not be built for reasons of
budget and time pressure.

Question: would Galileo have used the main antenna to receive signals
from the atmospheric probe and, if so, would the relay spacecraft be
supposed to replace Galileo in this function?  If not, could the
atmospheric probe's data be returned even if the orbiter is not
captured into orbit about Jupiter, but instead flys by Jupiter on
a path that would return it to the inner solar system?

    Paul F. Dietz
    [e-mail]

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

Date: 28 Apr 91 17:41:14 GMT
From: swrinde!sdd.hp.com!samsung!transfer!lectroid!sw.stratus.com![e-mail]  (Tarl Neustaedter)
Subject: Re: Galileo works?

In article <[e-mail]>, [e-mail] (Fraering Philip) writes:
> I heard from a friend over here (who I guess heard it on the news)
> that the moment of inertia for the Galileo probe is totally in
> agreement with a correctly-performed antenna deployment. In short, the
> antenna deployed, but the sensor doesn't know (sound familiar to
> anyone?).

Uh, no. According to av week (apr 25 p 25), the antenna is less than
half deployed. I believe I'm allowed to quote a few paragraphs from
av week without violating copyright. The comment about rate of spin is
at the end.

 Deployment normally takes under 3 min. before microswitches
 on the ballscrew mechanism shut off the dual driver motors.
 But on Apr.11 the motors were shut off after 8 min. by a software
 timer, and motor current telemetry indicates they ran normally for
 about the first 17 sec., or 7 deg. of rib rotation [out of 68 deg.],
 then slowed until they stalled at about 50 sec. [1 sentence deleted].

 One of the ribs partially obscured a Sun sensor behind the antenna,
 indicating it was between 34 and 40 deg. of deployment. By integrating
 the motor current to determine the ring position, engineers estimated
 the HGA had a lopsided deployment, with the opposite ribs at about
 17 deg. and the ring bending the ballscrew.

 The degree of HGA opening matches the change in spin rate seen in
 Galileo.

HGA is "high gain antenna". Please correct your friend. You may want to
get the current (apr 25) issue of aviation week for a more detailed
explanation.
-----------------------------------------------------------
         Tarl Neustaedter    [e-mail]
         Marlboro, Mass.    Stratus Computer
Disclaimer: My employer is not responsible for my opinions.

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

Date: 29 Apr 91 05:12:32 GMT
From: agate!bionet!uwm.edu!zaphod.mps.ohio-state.edu!mips!ptimtc!nntp-server.caltech.edu![e-mail]  (David Palmer)
Subject: The state of Galileo

According to the information I have (from someone with an instrument
on the probe) they have not tried anything at all to deploy the
antenna, beyond the nominal command.

When they discovered that the antenna had not deployed properly, the
first thing they did was decide whether it would hurt the antenna
to just leave it the way it was for a while.  Once that was decided,
they set up a tiger team to analyze the situation.  The tiger team
does not report back until May 10.

There are a lot of things they can try.  For instance, there are
two motors on the antenna deployment mechanism, but only one is
normally used.  Using both motors may force it open.  They may
pulse the motors, to try to shake it open.  They may shake the
spacecraft other ways as well.  These are just my uninformed
guesses as to possible solutions.

It is far too early to decide that there is no hope for the current
antenna.

--
        David Palmer
        [e-mail]
        ...rutgers!cit-vax!gap.cco.caltech.edu!palmer
    "Operator, get me the number for 911"  --Homer Simpson

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End of SPACE Digest V13 #478
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