Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_3/V16NO330.TXT

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Date: Thu, 18 Mar 93 05:18:28
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #330
To: Space Digest Readers
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Space Digest                Thu, 18 Mar 93       Volume 16 : Issue 330

Today's Topics:
                           Aurora spotted ?
                         fixing Galileo's HGA
        Flight time comparison: Voyager vs. Gallileo (3 msgs)
                         Lunar ice transport
                          Mars - J.B. Welch
                           Mars - J B Welch
                          NASA and congress
                            NASA Paperwork
                          Retraining at NASA
                        SpaceStation and SSTO
    Water Simulations (Was Re: Response to various attacks on SSF)

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

Date: Wed, 17 Mar 1993 15:52:29 -0500
From: Lawrence Curcio <[e-mail]>
Subject: Aurora spotted ?
Newsgroups: sci.space

How do you know this isn't an ordinary extraterrestrial UFO ?

-Larry

P.S...... :)

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

Date: Wed, 17 Mar 1993 20:05:10 GMT
From: Jeff Bytof <[e-mail]>
Subject: fixing Galileo's HGA
Newsgroups: sci.space

Is there any way that sunlight could be focused on critical areas
of the antenna mast to heat it?  Are there reflective components, perhaps
instruments on the scan platform that could focus a beam via optical
reflection?

-rabjab

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

Date: Wed, 17 Mar 93 17:48:06 GMT
From: Hayim Hendeles <[e-mail]>
Subject: Flight time comparison: Voyager vs. Gallileo
Newsgroups: sci.space

I have a general question, I hope someone can help with.

In 1977, the Voyager spacecraft was launched towards Jupiter,
and took approximately 2-3 years to get there without any gravity
assists. Yet, the Gallileo spacecraft is taking 6 (?) years to reach
Jupiter - and that's with 3 gravity assists! Why is there such a big
difference? Is this another fiasco due to the Space Shuttle?

Another question on the same topic, concerns our inability to send a
mission to Pluto. I remember, back in the 70's, they considered sending
one of the Voyager's to Pluto via a gravity assist at Jupiter. I don't
remember the details, but I do remember the flight times were not that
excessive.  Now since the Earth, Jupiter and Pluto are in the same
relative positions every 13-14 years (approximately - if I guess
correctly), this type of mission should be quite feasible again, with a
reasonable flight time. So why isn't it a "simple" matter to launch
a Voyager-type spacecraft to Jupiter?

Thanks,
Hayim Hendeles

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

Date: 17 Mar 93 20:35:42 GMT
From: Tim Thompson <[e-mail]>
Subject: Flight time comparison: Voyager vs. Gallileo
Newsgroups: sci.space


In article 175524 (Hayim Hendeles) writes
> I have a general question, I hope someone can help with.
>
> In 1977, the Voyager spacecraft was launched towards Jupiter,
> and took approximately 2-3 years to get there without any gravity
> assists. Yet, the Gallileo spacecraft is taking 6 (?) years to reach
> Jupiter - and that's with 3 gravity assists! Why is there such a big
> difference? Is this another fiasco due to the Space Shuttle?
>
   I think the answer is yes. I don't remember what kind of booster Voyager went
up on, but whatever it was, it had a helluva lot more poop than the booster
Galileo had to ride out of the shuttle. With nowhere near enough thrust to just
get there in a reasonable time (or at all?), the VEEGA trajectory was about
the only way to get there.

> Another question on the same topic, concerns our inability to send a
> mission to Pluto. I remember, back in the 70's, they considered sending
> one of the Voyager's to Pluto via a gravity assist at Jupiter. I don't
> remember the details, but I do remember the flight times were not that
> excessive.  Now since the Earth, Jupiter and Pluto are in the same
> relative positions every 13-14 years (approximately - if I guess
> correctly), this type of mission should be quite feasible again, with a
> reasonable flight time. So why isn't it a "simple" matter to launch
> a Voyager-type spacecraft to Jupiter?
>
   For voyager, as I recall, the choice was between Titan or Pluto, there was no
trajectory that would get both. The Voyager folk pickec Titan, as the only moon
with an atmosphere, and the weird possibilities of life, of nitrogen seas, etc.
As it turned out, Titan was interesting, but I would have preferred Pluto.
   There is a Pluto mission in progress, the "Pluto Fast Flyby" I think. It is a much
smaller than Voyager type craft, to keep mission expense down. I don't think it's
shuttle launched, but since it's small, the boosters we have will do the job. At
the moment, I don't think the U.S. has anything that will launch anything of
Voyager size from earth.

> Thanks,
> Hayim Hendeles

---
ALL OPINIONS EXPRESSED ARE MINE, ALL MINE, TOTALLY MINE, I MADE THEM UP MYSELF.
------------------------------------------------------------
Timothy J. Thompson, Earth and Space Sciences Division, JPL.
Assistant Administrator, Division Science Computing Network.
Secretary, Los Angeles Astronomical Society.
Member, BOD, Mount Wilson Observatory Association.

INTERnet/BITnet:    [e-mail]
NSI/DECnet:         jplsc8::tim
SCREAMnet:          YO!! TIM!!
GPSnet:             118:10:22.85 W by 34:11:58.27 N

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

Date: Wed, 17 Mar 1993 20:11:13 GMT
From: Henry Spencer <[e-mail]>
Subject: Flight time comparison: Voyager vs. Gallileo
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Hayim Hendeles) writes:
>In 1977, the Voyager spacecraft was launched towards Jupiter,
>and took approximately 2-3 years to get there without any gravity
>assists. Yet, the Gallileo spacecraft is taking 6 (?) years to reach
>Jupiter - and that's with 3 gravity assists! Why is there such a big
>difference? Is this another fiasco due to the Space Shuttle?

No, the fundamental problem is that Galileo really could have used a
trip to the fat farm.  Galileo is much, much heavier than the Voyagers,
to the point where it can only barely fly its intended mission.  Its
weight growth during development was nothing short of spectacular.

Originally it wasn't going to need the gravity assists, but only
because it was going to use the heaviest booster combination the US
had -- Shuttle plus Centaur.  When Centaur was banned from the shuttle
after Challenger, the gravity assists became necessary.

Had Galileo stayed within earlier weight targets, the IUS that boosted
it into the gravity-assist trajectory could have sent it direct to
Jupiter, like Ulysses.

>Another question on the same topic, concerns our inability to send a
>mission to Pluto. I remember, back in the 70's, they considered sending
>one of the Voyager's to Pluto via a gravity assist at Jupiter...
>... Now since the Earth, Jupiter and Pluto are in the same
>relative positions every 13-14 years (approximately - if I guess
>correctly), this type of mission should be quite feasible again, with a
>reasonable flight time. So why isn't it a "simple" matter to launch
>a Voyager-type spacecraft to Jupiter?

It's feasible, and the Pluto people looked at it -- see their IAF paper
last summer.  It even gives you a substantially heavier spacecraft.  The
problem is that, between the wait for the launch window and the longer
trip time, it gets to Pluto considerably later than a small spacecraft
launched direct by a heavy booster.  This particular mission is somewhat
time-critical because Pluto's atmosphere will start to freeze out in
20-30 years.

One reason for the longer flight time, incidentally, is that Jupiter's
Van Allen belts require extraordinary radiation-hardening for the
electronics of any mission that's going to get really close to Jupiter.
If you've got both time and budget constraints on the spacecraft
development process, you can't get too close to Jupiter, and that
limits the benefit from gravity assist.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

Date: Wed, 17 Mar 93 20:34:03 GMT
From: Ross Borden <[e-mail]>
Subject: Lunar ice transport
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Ross  Borden) writes:
>>be buried in the regolith (an excellent insulator).  Does anyone know
>>what the mean temperature of regolith is at, say, 2 meters ?
>
>We only have a few data points, but they're all within a degree or two
>of 255K.  The variation is from site to site -- the temperature at any
>particular site is absolutely constant at that depth.

    So, if you were to preheat the pipeline by injecting superheated
steam, could you pump water at, say, 100C the entire length without reheating?
    Gary Coffman mentions using steam instead of water, but its not clear
to me why.  Is it for ease of pumping?  I would think that you would be able
to deliver more mass using liquid phase.

-------------------------------------------------------------------------------
|  I shot a man just to watch him die;    |     Ross Borden                   |
|  I'm going to Disneyland!               |     [e-mail]            |
-------------------------------------------------------------------------------

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

Date: 17 Mar 1993 15:32:02 -0600
From: [e-mail]
Subject: Mars - J.B. Welch
Newsgroups: sci.space

You're on the wrong group.

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

Date: 17 Mar 1993 14:29:37 -0600
From: [e-mail]
Subject: Mars - J B Welch
Newsgroups: sci.space

I disagree. JB can handle the design and project management aspects
of the project. His record from the late '70's shows that he
can handle the load.
His projections show no severe cost overruns and it appears that he
is on schedule for a mid 1994 launch.

f.e.d.s.o.y.u.

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

Date: Wed, 17 Mar 1993 19:33:59 GMT
From: Brian Donnell <[e-mail]>
Subject: NASA and congress
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Tom) wrote:
>
> I'm curious to know what it is you think I've been mislead on.  If you
> belive I'm misinformed about real problems existing at NASA, then you've
> been highly insulated.  Some of us that make up 'the public' do care, and
> have learned of such problems.  My assertation is that the worst problems
> are inherent in NASA's nature, and that correcting those problem means
> destroying NASA.  Maybe replacing it, maybe balkanizing it.
>

I did not intend to imply that your conception of problems within NASA
was incorrect. What I was referring to was the fact that most of the
public does not have a true scope of the enormous breadth and difficulty
of NASA's programs.  NASA is designing systems to operate in an environment
where there is very little past experience. While there have been and will
continue to be failures, there have also been many successes.
I do believe that space will have to be commercialized before it is widely
accessible, but the tasks to be surmounted are so large right now that only
the government has the financial resources to do it.

> Flubs I can deal with.  We're all human here; mistakes get made.  But
> some mistakes are systemic.  And here you are, saying PR isn't good
> enough.  The problem is not the public learning of NASA's flaws.  The
> problem is NASA's flaws being ignored.  Better PR will only exacerbate
> the problem.
>

This is not true. The Augustine report had major impact on NASA operations
and philosophies. It is a learning experience, I assure you.  I think NASA
should be held accountable for its mistakes and the public (i.e., the
customer) should be kept aware. However, to be fair (and this was my
original point), the PR should include the successes as well as the
failures.
The media has always harped on the bad (like they do in everything).  I
feel
until recently NASA has done a pathetic job in showing off its successes.
There is a great annual publication which comes out called NASA Spinoffs.
However, it is almost impossible to get a copy.  Something like this should
be mass marketed and at every library in the country.

> I have are those that result from NASA's nature as a gov. agency.
> Slowness to respond to circumstances.  Projects being directed by
> political, not design and cost concerns.  This is why the classic
> 'congresses fault' defense is bogus.  Since much of NASA's history
> and funding has come from congress-directed goals (Shuttle, Apollo,
> Fred), problems with congress are problems at NASA's heart.  You
> can't work around them, but the people at NASA could get out from
> under them.
>

I actually somewhat agree with this. But private industry does not have
the financial muster to develop all the core technology to utilize
space.  Rather than destroy the one entity that does, I think Congress
should be educated and forced by the voters to remove these barriers
to national research and technology development.

> >collection of private consortiums could have done *any*
> >better with the given resources.  I know this is a
>
> With the given resources, I disagree.  With their own resources, I think
> they could still do it, or at least some of it.  But this is an untestable
> hypothesis, as NASA has created a record of monopoly action;  doing their
> best to ruin competition, with gov. subsidy advantages.  People won't
> keep putting their fortunes on the line to see them destroyed by a
> monopoly with political, not creative, motivations.  This, I think, is

I would like to remind you that the vast majority of actual work on
NASA programs is done by private industry (Rockwell, McDonnell Douglas,
IBM,
etc.) under the direction of NASA.  NASA has one of the most ambitious
programs for giving work to small minority-owned and disadvantaged
businesses.
I personally have seen (and recommended) many small-business innovation
research programs (SBIRs) funded by NASA for commercial launch vehicles.
One major component of NASA's charter that has taken on more emphasis now
than ever before is technology transfer into the private sector.  The goal
has always been to develop the core technologies to a point where the
proven methods of capitalist investments can take over.

> the most damaging aspect of NASA.  What good is the practical knowledge
> gained by NASA, if it doesn't get used to better our lives?
>

You really should try to get a copy of NASA Spinoffs that I mentioned.
Contact the Public Affairs Office at Johnson Space Center:
713-483-5111

> Given the same resources, what special skill/quality does NASA posess
> that would make it more effective than a private group?
>

The money and the freedom to draw on a pool of national collective
resources.
The task to be done are too mounmental still to be attempted by multiple
companies duplicating efforts in competition. We need all American
resources
to contribute a different part.

> What's wrong with breaking NASA into it's component pieces, and allowing
> them to get funding based on thier results.  Then, the Shuttle ops,
> a monopolized, inefficient transportations system, would no longer be
> supported by a public that likes what JPL does.  I bet we'd have a
> CRAF, if it had been done that way.

I don't oppose this at all. The only thing that is critical is that some
power be maintained in integrating all efforts into a common set of goals.
This, btw, *is* NASA's biggest internal weakness.  There has been way too
little effort devoted to central integration issues of all the various
programs devoted to a project (case and point - Space Station).

>
> >Most (if not all) of the frustrating shortcomings in Shuttle
> >and Station are due to inadequate, unrealistic and
> >fickle funding.  The technological know-how within NASA
> >is there.  The bureaucracy of government procurement
> >forced on NASA is another stumbling block.  If Congress
> >could find the wherewithal to commit to a multi-year
> >project, we might have had Station years ago.
>

> BTW, we did have a station years ago :-)  It died because of actions
> of NASA & Congress.
>

Skylab did not have the capability to be a permanently manned station.
However, I do agree that we as a nation have dragged our feet way too long.

> There are goals in space that would be better met by private free
> enterprise.  Yet NASA has consistently blocked these efforts, trying
> to protect the Shuttle, for example, from competition in launching
> services.  Do you defend this as well?
>

No, I would not defend it - if it were true. Can you enlighten me?
Everything I have seen from NASA Headquarters has encouraged
commercialization
of space.

Brian Donnell
NASA/JSC

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

Date: Wed, 17 Mar 1993 20:24:52 GMT
From: Henry Spencer <[e-mail]>
Subject: NASA Paperwork
Newsgroups: sci.space

In article <[e-mail]> [e-mail] ("F.Baube[tm]") writes:
>Was this mallet whack noted in the paperwork ?
>
>If so .. Who signed off on it ?  Wasn't there a procedure to
>require an assessment of the possible effect of a mallet whack ?
>Or did some assembly tech just do it and not have to tell anyone ?

Typically several people signed off on it.  The problem is not that it
wasn't properly authorized, but that the engineers who came up with it
didn't examine the implications properly before starting the paperwork
to authorize it.

Freeman Dyson (I think it was) noted a while ago that most big high-tech
projects that are conspicuously successful have a chief engineer, or
someone along those lines, who knows *everything* about the project,
stays with it from start to finish, and bets his career and reputation
on it working.  That's the sort of person who notices design botches
before they turn into failures.  Revolving-door paperwork pushers don't.

The other side of this is that just because several people sign off
on it, doesn't mean it was done right.  You may recall an incident a
few years ago where a work-platform support beam was left in the
engine compartment of one of the shuttle orbiters, undiscovered until
it went CLUNK as the orbiter was being hoisted into a vertical position
for stacking.  There were three signatures saying it had been removed.

>In either case, what then is the point of all the paperwork,
>if it can't stop simple mechanical problems caused during
>spacecraft assembly ?

There isn't much point to it, actually.  The theory behind paperwork
is that it eliminates the need to hire and retain competent people.
Attractive to bureaucrats, but it doesn't work.

While *some* record-keeping is necessary, well-run projects need much
less of it.  The SR-71's paperwork lets Lockheed trace every part to
the piece of titanium it was made from... and there is *still* far
less paperwork for the Blackbirds than for a typical USAF fighter.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

Date: Wed, 17 Mar 1993 20:09:14 GMT
From: Brian Donnell <[e-mail]>
Subject: Retraining at NASA
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Nick Szabo)
wrote:
[...various foam-at-the-mouth drivel deleted...]

Nick -
  I am sorry you harbor some personal bitterness against NASA. I fail to
understand why you think a personal attack on a public forum such as this
would command any respect whatsoever. Constructive criticism is a valuable
thing.  Many of the comments put forth by you and others are clearly
informed. However, you destroy any credibility you might have had with
dissertations such as your last. I frankly hesitated to even grace it
with a response. Is it your wish to truly motivate change for what you
perceive as incorrect, or to merely throw tantrums for all to see?
(Cross-posting to alt.flame was particularly silly, Nick.)

I apologize for taking so long to reply.  I was busy spending your
tax dollars on something more constructive. I think the use of
my time to offset the nay-sayers like you in the public eye is NASA money
well spent.

Now onto Allen's comments...

In article <[e-mail]>, [e-mail] (Allen W. Sherzer)
wrote:
>
> Talk to SDIO. Their support infrastructure for SSRT represents less then
> 1/60 of the program cost. Yet they are doing more to support cheap routine
> access to space than NASA has ever done.
>

Allen -

Good stuff, I agree. But SDIO's efforts are narrower in scope than the
overall goals of NASA, e.g., permanent manned presence, thorough
exploration
of the solar system (manned and unmanned), etc.
BTW - I disagree with the previous estimate of infrastructure costs being
50% of NASA's overall costs.  Before we quibble about this - why don't
you list what you consider to be infrastructure (civil service, maintenance
of existing programs, etc.).

> Agreed that is a problem. Yet other parts of government deal with the
> same problems all the time.
>

Other govt agencies due not have to deal with unknown and volatile domains
to the extent that NASA does.

> Clementine, Delta Clipper, Timberwind...  I'll stack SDIO's record for
> promoting space against NASA any day. Better, cheaper, faster is new
> to NASA but it was always SOP at SDIO.
>

For their focused domain, these are good. But I will bring us back to the
big-picture point again that NASA has to keep in mind.

Brian Donnell
NASA/JSC

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

Date: 17 Mar 93 19:25:51 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: SpaceStation and SSTO
Newsgroups: sci.space

Organization: Evil Geniuses for a Better Tomorrow
Lines: 27
Sender: [e-mail]
Source-Info:  Sender is really [e-mail]

In article <[e-mail]> [e-mail] (Scott A Koester) writes:

>With SSTO coming around, and
>quite possibly having this transfrom into the DC-Y program, has any

Note that only a suborbital prototype is coming around. Without pressure
form us there won't be an orbital SSTO built. Have you written Gore yet?

>consideration been done, on maybe having these craft dock with the SSFII?

A Delta Clipper could indeed dock with SSF (or whatever is built; if anything
is built). In fact, 30 years of logistics would cost about $8 billion
using DC (this includes the total development cost of DC).

This compares to about $80 billion if you use Shuttle.

Note that DC is not being built with this in mind but it IS a posibility.
If NASA would open station logistics to the lowest bidder we would likely
have several SSTO's to choose from by 1998.

   Allen

--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
|  [e-mail]     |  nothing undone"                                       |
+----------------------91 DAYS TO FIRST FLIGHT OF DCX-----------------------+

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

Date: Wed, 17 Mar 1993 19:54:58 GMT
From: Henry Spencer <[e-mail]>
Subject: Water Simulations (Was Re: Response to various attacks on SSF)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>... I think water tanks and practicing on them is
>a great idea. However, to assume that we can corelate actions in the tank
>to the actions needed to assemble a large space structure (like Freedom)
>in free fall is foolish.

As a minor case in point, something that got mentioned at Making Orbit...

There are two things really wrong with the water-tank simulation of free
fall.  One is that you are lying in your suit rather than floating in it.
The other is the more obvious issue:  the water has viscosity.

When exiting the shuttle airlock, you reach out and grab a handrail
above the door, and then push off outward.  Apparently, *everyone* who
tries this for the first time in free fall after water-tank practice
bonks his helmet against the outside of the airlock, by pushing off
too hard and helplessly pivoting too far around the handrail.  Even
if he's been warned about the problem.

Not very significant in itself, but an indication of what you can run
into.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

End of Space Digest Volume 16 : Issue 330
------------------------------