Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v09_4/v9_412.txt

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Subject: SPACE Digest V9 #412

SPACE Digest                                      Volume 9 : Issue 412

Today's Topics:
          NASA Prediction Bulletins:  Space Shuttle
          NASA Prediction Bulletins:  Space Shuttle
             Re: Magellan update
        manned vs. unmanned (was: Priorities at NASA?)
           Re: Some comments on comments...
             Re: Magellan update
              Re: Smart Pebbles
        Re: Private spending for space science
             Re: Magellan update
               JPL info needed.
              Re: Voyager model
         Re: Brilliant (but old hat) Pebbles
        Re: Private spending for space science
----------------------------------------------------------------------

Date: 5 May 89 00:33:13 GMT
From: [e-mail]  (TS Kelso)
Subject: NASA Prediction Bulletins:  Space Shuttle


The most current orbital elements from the NASA Prediction Bulletins are
carried on the Celestial RCP/M, [phone], and are updated several times
weekly.  Documentation and tracking software are also available on this
system.  As a service to the satellite user community, the most current
elements for the current shuttle mission are provided below.  The Celestial
RCP/M may be accessed 24 hours/day at 300, 1200, or 2400 baud using 8 data
bits, 1 stop bit, no parity.

STS-30
1 19968U          89124.81499201  .00087149  00000-0  25599-3 0    28
2 19968  28.8878 340.6496 0006169 266.1842 346.0076 15.91174232    00
--
Dr TS Kelso                           Asst Professor of Space Operations
[e-mail]          Air Force Institute of Technology

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

Date: 5 May 89 22:39:53 GMT
From: [e-mail]  (TS Kelso)
Subject: NASA Prediction Bulletins:  Space Shuttle


The most current orbital elements from the NASA Prediction Bulletins are
carried on the Celestial RCP/M, [phone], and are updated several times
weekly.  Documentation and tracking software are also available on this
system.  As a service to the satellite user community, the most current
elements for the current shuttle mission are provided below.  The Celestial
RCP/M may be accessed 24 hours/day at 300, 1200, or 2400 baud using 8 data
bits, 1 stop bit, no parity.

STS-30
1 19968U 89 33  A 89124.95919992  .00087028  00000-0  25599-3 0    37
2 19968  28.8865 339.5883 0006210 249.6494 110.2994 15.91147694    23
--
Dr TS Kelso                           Asst Professor of Space Operations
[e-mail]          Air Force Institute of Technology

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

Date: 3 May 89 16:51:25 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Magellan update

In article <[e-mail]> [e-mail] (Jonathan Leech) writes:
>>The reason for the savings on propellant is that with the
>>later launch date the path to Venus is more direct, resulting in fewer TCMs.
>
>    So, why didn't they plan to launch as early as possible in the
>window, then leave it in orbit until the optimal time for Venus
>injection? Atmospheric drag?

Not significant over that short a period, I'd say.  But if I'm not mistaken,
the IUS has a very limited period of autonomous operation; for example, it
has no solar panels and limited battery capacity.  Magellan would probably
be reasonably happy about it, perhaps with some minor modifications, but
the IUS isn't designed to be parked in orbit for any length of time.
--
Mars in 1980s:  USSR, 2 tries, |     Henry Spencer at U of Toronto Zoology
2 failures; USA, 0 tries.      | uunet!attcan!utzoo!henry [e-mail]

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

Date: 3 May 89 18:19:17 GMT
From: umigw![e-mail]  (steve emmerson)
Subject: manned vs. unmanned (was: Priorities at NASA?)

A while back, I help start the "manned vs. unmanned" debate by opining
that the manned program often obtains funding at the expense of the
unmanned.

As I recall, Mr. Spencer disagreed.  He maintained, I believe, that unused
funds from the the unmanned program are returned to the treasury rather
than being diverted to the manned program.

He may be right.

On the other hand, I didn't think that observation very relevant as
I had in mind the congresional budgetary process rather than
program cutbacks decided upon by the NASA administration (for whatever
reason).  But, being a shy person, I didn't post a response ;-).

The referenced posting is, however, too golden an opportunity to pass up.
I interpret the testimony as supporting the proposition that the manned
and unmanned programs compete for funding.

Of course I'm wrong ;-).  Henry?
--
Steve Emmerson                     Inet: [e-mail] [128.116.10.1]
SPAN: miami::emmerson (host 3074::)      [e-mail]
UUCP: ...!ncar!umigw!steve               [e-mail]
"Computers are like God in the Old Testament: lots of rules and no mercy"

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

Date: 2 May 89 19:03:05 GMT
From: mcdchg!clyde![e-mail]  (Forrest Gehrke)
Subject: Re: Some comments on comments...

In article <[e-mail]>, [e-mail] (Henry Spencer) writes:
> The Soviets have had schedule slips.  However, while the US program is
> pretty nearly all talk and no action, the Soviet one is mostly talk but
> some action.  They have, after all, launched two more Mars missions this
> decade than the US has.
> --
> Mars in 1980s:  USSR, 2 tries, |     Henry Spencer at U of Toronto Zoology
> 2 failures; USA, 0 tries.      | uunet!attcan!utzoo!henry [e-mail]

Aside from all of the above, I read somewhere (source unremembered)
that the Russians lost one of their Phobos probes due to an
inadvertant steering of the probe's antenna away from earth
by a ground controller.  The same article mentioned that the
Magellan has an automatic sequence for the antenna dish to
seek earth in such an event.  Can anyone vouch for this
report?

Seems like such an obvious measure; I wonder why the Russians
failed to take it into account?

   Forrest Gehrke

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

Date: 3 May 89 14:49:10 GMT
From: att!cbnewsl![e-mail]  (Stuart Warmink)
Subject: Re: Magellan update

In article <[e-mail]>, [e-mail] (Jonathan Leech) writes:
> [later Magellan launch windows are more fuel efficient]
>     So, why didn't they plan to launch as early as possible in the
> window, then leave it in orbit until the optimal time for Venus
> injection? Atmospheric drag?

The batteries of the IUS and Magellan would run out of juice - Magellan's
solar panels won't be deployed until after the IUS burns.
--
------------------------------------------------------------------------------
"Captain, I see no reason to stand here  |  Stuart Warmink, Whippany, NJ, USA
 and be insulted" - Spock                | [e-mail] (att!cbnewsl!sw)
-------------------------> My opinions are just that <------------------------

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

Date: 3 May 89 16:48:52 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Smart Pebbles

In article <[e-mail]> [e-mail] (Neal Woodall) writes:
>>Yeah, it looked really neat.  Just one question: What's the difference
>>between the smart pebble concept and placing smart interceptor
>>missiles in orbit?
>
>Not much, as far as I can discern...

The "brilliant pebble" idea is to build *lots* of seriously small (mass
measured in *grams*, not kilograms) interceptors which are very highly
intelligent.  Many of the trickier problems of SDI arise from interceptors
being expensive and in short supply.  If they are cheap and abundant, you
don't *need* 100%-reliable discrimination of warheads from decoys, and you
don't *need* one-shot kills, and you don't *need* 100% performance from
the hardware in general.  Making them largely autonomous eliminates a lot
of the coordination problems; it means there will be overlap and redundancy
and some will be wasted, but if they're cheap and abundant, who cares?
Things like the "arm" and "disarm" decisions can still be centralized.

Now, how practical this is... is a good question.  Lowell Wood says that
something like 30 grams is enough to kill an ICBM.  Nobody, not even him,
expects to get the things anywhere near that small any time soon, but it
should be possible to do much better than the many-kilogram designs for
orthodox kinetic-energy weapons.  There are big questions about sensors,
software, and production costs yet to be dealt with, but the basic concept
does look better than conventional space-based interceptors.
--
Mars in 1980s:  USSR, 2 tries, |     Henry Spencer at U of Toronto Zoology
2 failures; USA, 0 tries.      | uunet!attcan!utzoo!henry [e-mail]

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

Date: 3 May 89 20:51:17 GMT
From: phoenix![e-mail]  (Keith P. Mancus)
Subject: Re: Private spending for space science

In article <[e-mail]> [e-mail] (Henry Spencer) writes:

<Why assume that *industry* has to do it?  What about the National Geographic
<Society?  Or a university consortium?  Useful probes could be brought in at
<a pricetag, even including launch at current prices, that a major fundraising
<drive by such institutions could cover.  The hardware that Amsat uses for
<Clarke-orbit amateur comsats would do for a lunar orbiter (the propulsion
<requirements, in particular, are almost exactly the same for Clarke orbit
<and lunar orbit), and inner-solar-system planetary missions are not all that
<much more difficult.  Jupiter is a bit trickier but not impossible.
<
<It *would* help a lot if the launch costs came down, though.
<
<But there are few plausible scenarios for such things as long as it looks
<easier to convince Congress to pick the taxpayers' pockets to pay for it.

    I think this is especially true if you consider that NASA has never
made any real effort to make money off of the very real demand for
color photos of various objects in the solar system.  Presumably the NGS
would not overlook this chance to get some of the money back.  Perhaps
when NASA's budget falls low enough...

--
-Keith Mancus <[e-mail]>
              <[e-mail]>  <- preferred
-------------------------------------------------------------------
"We're going to space if we have to walk."   -Jerry Pournelle, 1983

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

Date: 4 May 89 03:46:44 GMT
From: [e-mail]  (Peter G. Ford)
Subject: Re: Magellan update

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Jonathan Leech) writes:
>>    So, why didn't they plan to launch as early as possible in the
>>window, then leave it in orbit until the optimal time for Venus
>>injection? Atmospheric drag?
>
>Not significant over that short a period, I'd say.  But if I'm not mistaken,
>the IUS has a very limited period of autonomous operation; for example, it
>has no solar panels and limited battery capacity.  Magellan would probably
>be reasonably happy about it, perhaps with some minor modifications, but
>the IUS isn't designed to be parked in orbit for any length of time.

The Magellan spacecraft would be quite happy to stay parked. In fact,
it deploys its solar panels before the IUS first stage is fired --
sounds stupid, but the STAR-48 Venus injection motor produces much
higher g-forces.  Anyway, better to deploy the panels than to risk
contaminating them with IUS exhaust.

Peter G. Ford <[e-mail]>
MIT and Magellan Project

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

Date: 2 May 89 21:18:53 GMT
From: att!mtuxo!mtgzz!drutx!druhi![e-mail]  (Sue Hendrix)
Subject: JPL info needed.


I have a friend who needs some info on JPL doings.

Specifically, what probes are out there now that JPL is keeping
an eye on, and getting telemetry from?

(This is to be used in a GURPS based role-playing game--a present
day espionage-type game set at JPL.  So if any of you JPL types
out there have any other ideas for the game, feel free to contribute.
Please mark it as spoiler if you do, as I will be playing, and don't
want to know more than is good for me.)

Thanks.
--
                                      Sue Hendrix, net.goddess
                                      att!drutx!druhi!suelh

It's a beautiful day, let's go boating.

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

Date: 4 May 89 01:19:18 GMT
From: crdgw1!ge-dab!sunny![e-mail]  (Gregory Harrison)
Subject: Re: Voyager model

>The "Voyager" on display here is a model made out of cardboard, plastic,
>wood, occasionally metal.  I believe the third craft is in the Smithsonian.

There is another.  As president of DeVry Institute of Technology L5 Society,
the chapter made a ~1/2 scale 95% accurate model of Voyager.  We had JPL plans
and photos, and the model is suspended in the Library in the Columbus OH
DeVry Institute of Technology.  I think it came out beautifully.

Greg Harrison
The expressed opinions are mine, and are not meant to reflect those of GE.

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

Date: 4 May 89 06:28:01 GMT
From: vsi1!daver!lynx![e-mail]  (Neal Woodall)
Subject: Re: Brilliant (but old hat) Pebbles

In article <[e-mail]> [e-mail] (Timothy Roberts) writes:

>    The Dragon uses 36(?) one shot solid fuel motors set
>    around its waist like rows of tiny funnels.

This sounds very much like the FLAG-E (Flexible Lightweight Agile Guided
Experiment) that was tested as part of a hyper-velocity atmospheric ICBM
interceptor experiment a few years ago (during the hey-day of the SCI
funding under the Reagan administration).

>    So what?  I am glad you asked.  Put the sight on the missle and
>    you don't need a wire.  Put the IR source on a missle plume and
>    you've got Brilliant pebbles.  This thing is circa Viet Nam War
>    and I have toted them all over Hawaii, Okinawa, and Thailand
>    during my days in the Marine Corps.

You make it sound so easy....but remember: the distance between "concept"
and "working prototype" in "project space" is often quite deceiving.
Putting the real-time inertial control onboard and having the rockets
fire controlled bursts (look at the video...the motors look like
liquid fueled to me) is probably more expensive than you think.

>    I like big science.  I detest weapons based in space.  The
>    Peace Shield will make a lot of engineers rich and destabilize
>    the current nuclear standoff.

I agree with you about the "big science" and "space based weapons", but if
you think any "engineers" will get rich off of this, you are mistaken. Maybe
some big conglomerates will reap tremendous profits, but the guys who do
the actual work will still get their regular salaries, and I know from
experience, this is no way to get rich!


Neal

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

Date: 4 May 89 18:28:06 GMT
From: mentor.cc.purdue.edu!l.cc.purdue.edu![e-mail]  (Herman Rubin)
Subject: Re: Private spending for space science

In article <[e-mail]>, [e-mail] (John Roberts) writes:
>
> >From: agate![e-mail]  (William Baxter)
> >In article <[e-mail]>, jmckerna@polyslo (John McKernan) writes
> >>                               Why don't you
> >>speculate on just how much of their $500 million profits they'll voluntarily
> >>spend on planetary probes and manned space R&D and such.

>            ......................

> Can you think of a plausible scenario by which private industry would
> undertake to send sophisticated probes to Venus or Jupiter at its own
> expense in the next 20 years? (I can, but there are some undesirable
> side effects.)

We have millions of people who believe in funding space research.  What I
have been proposing all along is that these people be allowed to set up
corporations, profit and non-profit, for this purpose.  More than one will
be needed, because we have the manned vs unmanned dispute.

These corporations could act in concert with governments and industrial
firms.  But the US government must allow these corporations to act without
governmental approval.

Let the people who believe in space fund it.  But do not ask them to fund it
under the control of the government.
--
Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907
Phone: [phone]
[e-mail] (Internet, bitnet, UUCP)

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

End of SPACE Digest V9 #412
*******************