Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_5/V11_588.TXT

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Subject: SPACE Digest V11 #588

SPACE Digest                                     Volume 11 : Issue 588

Today's Topics:
         Receiving Hubble Photos - directly?
         Re: Phobos survey in the New Yorker
              Galileo Update - 06/27/90
              Re: Saturn Rockets
       Re: NASA Headline News for 06/26/90 (Forwarded)
        Re: More on NASA 91 Appropriation Vote
        Aim For The Moon Rocket Contest --> email list
              Slung into Space!
        Re: More on NASA 91 Appropriation Vote
Re: NASA announces next steps in Space Exploration Outreach Program (F

Administrivia:

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

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

Date: 28 Jun 90 16:48:42 GMT
From: [e-mail]  (Allen J. Baum)
Subject: Receiving Hubble Photos - directly?

[]

This may be completely pointless now, but...
A friend of mine would like to recieve pictures from the Hubble Space Telescope
directly from the downlink, much as one can currently do with weather satellite
pictures.

He needs information on frequencies, formats, and satellite positions. Where
can this information be obtained? Does anyone have pointers to this
information?

--
          [e-mail]        [phone]
{decwrl,hplabs}!amdahl!apple!baum

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

Date: 27 Jun 90 17:28:55 GMT
From: att!tsdiag![e-mail]  (Dave Tiller N2KAU)
Subject: Re: Phobos survey in the New Yorker

In article <[e-mail]> [e-mail] () writes:
>
>    I was waiting for my physical therapist to become free today ...

I've got a feeling you'll have a long wait. I've never seen a doctor _lower_
his rates!!!  Oh, maybe I misread this.  Is she having a divorce? That's it..
--
David E. Tiller         [e-mail]  | Concurrent Computer Corp.
FAX:  [phone]      Ph: [phone] (w) | 2 Crescent Place, M/S 117
UUCP: ucbvax!rutgers!petsd!tsdiag!davet        | Oceanport NJ, 07757
ICBM: 40 16' 52" N      73 59' 00" W           | N2KAU @ NN2Z

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

Date: 28 Jun 90 19:09:35 GMT
From: swrinde!zaphod.mps.ohio-state.edu!sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update - 06/27/90


                     GALILEO MISSION STATUS
                          June 27, 1990

     The Galileo spacecraft is now 92.8 million miles from Earth,
with the distance declining at about 300,000 miles per day.  The
round-trip light time is 16 minutes, 38 seconds.  The spacecraft
orbital speed is just over 54,000 mph, declining gradually as it
moves away from the Sun.

     At JPL, the Galileo navigation and orbiter engineering teams
have begin designing the third trajectory correction maneuver
since the Venus flyby last February.  This will continue the
process of precisely shaping the flight path for the December
1990 gravity-assist flyby of Earth. The finished maneuver
parameters will be transmitted to the spacecraft and executed in
mid-July.

     At the spacecraft, the activity level is very quiet, with
continued scientific measurements of the interplanetary
environment, periodic memory readouts of the data, and occasional
calibrations, Sun-point maneuvers and other engineering
housekeeping routines.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 28 Jun 90 17:01:56 GMT
From: pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Saturn Rockets

In article <[e-mail]> [e-mail] (Nick Watkins) writes:
>>     Basically, the IB took over its major missions.  In hindsight,
>>     the I was a dead end that probably shouldn't have been pursued.
>It was designed when there were no operational US LH2/LOX boosters, well
>before the RL10 engines first flew, on a Centaur, and when multiple
>flight tests were the norm. "All up" testing had to be sold against the
>misgivings of many at MSFC. Do you really think they could have started
>with the Saturn IB, and does anyone else share your opinion?

The comment comes from "Stages to Saturn", the NASA History book on the
Saturn development.  I don't see that starting with the IB would have
caused any extra problems.  It would have reduced the workload a bit by
eliminating a useless booster from the development cycle.  Since the RL-10
first flew on Centaur, the Saturn I was in no way crucial to LH2/LOX
development.  Since no Saturn other than the I used the RL-10, it was in
any case irrelevant to the Saturns except as a technology pathfinder for
the J-2.  And I don't see the relationship to "all up" testing at all.
You're going to have to explain more precisely just what role the I played
before I'll buy it.
--
"Either NFS must be scrapped or NFS    | Henry Spencer at U of Toronto Zoology
must be changed."      -John Osterhout |  [e-mail]   utzoo!henry

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

Date: 28 Jun 90 16:19:19 GMT
From: hplabsb![e-mail]  (David Smith)
Subject: Re: NASA Headline News for 06/26/90 (Forwarded)

In article <[e-mail]> [e-mail] (Chris Jones) writes:
>>orbiter Endeavor currently under construction
>
>Yoiks!  Weren't we all supposed to remember that as the Endeavour with a 'u'?
>Can't NASA remember these things?

Maybe they just came to their senses and translated the name into
American.

--
"Some fear that Newtonian physics    | David R. Smith, HP Labs
governs superpower relations:        | [e-mail]
What goes up must come down."        | [phone]
    Time Magazine, interviewing Gorbachev, June 4, 1990

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

Date: 28 Jun 90 21:03:06 GMT
From: agate!agate![e-mail]  (William Baxter)
Subject: Re: More on NASA 91 Appropriation Vote


In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:

>                                    the core
>SEI funding was to look for and analyze alternatives. The only thing the
>90 day study did was to convince the administration that NASA cannot be
>trusted to do this alone.

Yes, and the Space Station has been studied to death, too.  It is still
a project out of control.  I have seen nothing to indicate that the SEI
studies will be any different.  The conclusions of all the studies will
probably resemble the 90 day report far too closely.  Traxler and
company have nipped this problem in the bud.

--
William Baxter

ARPA: web@{garnet,brahms,math}.Berkeley.EDU
UUCP: {sun,dual,decwrl,decvax,hplabs,...}!ucbvax!garnet!web

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

Date: 29 Jun 90 04:29:16 GMT
From: sam.cs.cmu.edu![e-mail]  (Vincent Cate)
Subject: Aim For The Moon Rocket Contest --> email list


The idea of using small rockets to launch a very small payload into
space has generated enough interest that we have started a mailing list
just for this topic.  The list is "[e-mail]".  The purpose
of this list is to get together people who are interested in turning
this idea into reality.  All of the issues will be discussed (designs,
engines, safety, cost, transmitters, materials, balloons, funding,
legal issues, insurance, ...).  There are enough people on
rec.models.rockets that are only interested in the kind of rockets that
fit the legal definition of "model" that we really should move the
discussion from there to this new list.


If you are interested in this discussion please send your name and
email address to:

     [e-mail]


This name is used because Marc Ringuette already had the list sitting
around unused.  I will just be maintaining the list while Marc is out
of town.

Thanks Marc!!!!

    -- Vince

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

Date: 27 Jun 90 05:11:02 GMT
From: fernwood!portal!cup.portal.com![e-mail]  (H Keith Henson)
Subject: Slung into Space!


I hate to post a half-baked idea, but raising money for an email privacy
lawsuit has wiped out my time to bake it.  (Though I did get a patent
application filed.)

If you drop a 200-ton aircraft from 16 km (say 50,000 feet) to 6 km
(about 20,000 feet) the potential energy available is enough to raise a
one-ton payload to 2,000 km or to accelerate it to about 6.5 km/sec,
neglecting losses, of course.  The reason I choose 6.5 km/sec is that it
permits landing at the low end of a tether in a two-hour orbit without a
rocket stage.  It may turn out that it is better to use rockets for about
half the boost; a boost of 3 km/sec can be done with a very modest mass
ratio.

Using a cable and a sling maneuver to transfer energy from plane to
payload leads to an endpoint where the payload is going 6.5 km/sec in a
nearly circular path.  (At that point, you cut the cable at the payload
end with an explosive bolt).  Assuming firewalled engines develop 1/2 g,
the available force (weight plus engines) to keep the payload in a
circular path is about 300 tons.  A little high-school physics tells us
that a massless cable needs to be almost 15 km long to balance the
forces, and of course, the payload is undergoing about 300 gees of
acceleration.  While this is a little rough for people :-), a lot of
payloads, and all bulk materials would take it fine. (The ham sandwiches
might be a little mashed . . . )

Real tapered cables for this application seem to be marginally within
the state of the art; available materials give a section area at the
payload end of perhaps 6 square cm and an effective (accelerated) mass
perhaps twice that of the payload (implying three times as much aircraft
or one third of a ton payload).  The cable frontal area of about 300
square meters for a simple cylinder is too high, but presumably it can be
streamlined in section.  A 20-to-one reduction in effective area would
bring the frontal area down to 15 square meters.  The highest velocity
occurs when the cable is almost vertical.  This considerably reduces drag
effects (the payload and fastest section of the cable should be about 20
km high at release.)

The sling process starts by reeling a payload out from the aircraft (not
necessarily to the end of the cable) and entering a series of banking turns
to get the payload pendulumed out from the aircraft path.  Drop tanks on
the payload might be needed to increase the inertial/drag ratio in the
early part of this maneuver.  This would be followed by an involute
spiral turn with the bank turning into a roll before most of the altitude
loss.  The majority of the energy would be fed into the payload as the
plane followed an increasingly steep upside-down dive.  Forward
acceleration on the payload would average 20-30 gees over 30 seconds,
while the plane lost 10 km of altitude.  This is a bit toward the edge of
what you want to do with a big subsonic aircraft, but well within what
could be done with a specialized supersonic one.  The payload path would
be bent through approximately 3/4 of a circle in the horizontal plane and
a quarter circle in the vertical.

This is as far as I have time to take it at the moment.  Obviously it
need to be modeled.  Does anyone know of a program which can model a
sling?  Anyone have pointers to airfoil section data over the range of
velocities involved?  How about roll, etc. performance data on C5's and
747's?  Anybody have an opinion about hard points on these aircraft as to
where you anchor the rope?  Know anybody interested in funding some
studies or bootlegging them and co-authoring a paper?

Line forms over there for pilots who want to volunteer.

H. Keith Henson ([e-mail])

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

Date: 27 Jun 90 12:38:18 GMT
From: usc!samsung!umich!umeecs!itivax!vax3.iti.org![e-mail]  (Allen W. Sherzer)
Subject: Re: More on NASA 91 Appropriation Vote

[e-mail] (William Baxter) writes:
>>>We can all write to Bob Traxler and thank him for not allowing NASA to
>>>begin another large, ill-defined project

>>Before posting statements like this perhaps you should read what the
>>spending was requested for.

>I did.  That's why I said it.  Read the 90 day report again, Allen.

It is clear you did not read either the markup or the original request.
You seem to think that the SEI money requested was to work on one of the
architectures specified by the NASA 90 day study. Nothing could be more
incorrect. It is true that NASA (in typical style) has bundled a lot of
stuff (like ALS) into SEI that have nothing to do with it, but the core
SEI funding was to look for and analyze alternatives. The only thing the
90 day study did was to convince the administration that NASA cannot be
trusted to do this alone.

You also seem to think the SEI money was startup money. This dispite the
fact that the administration said several times that this is study money and
not startup money. The only exception to this was a $5M (out of 380M total
SEI request) startup request for Lunar Polar Orbiter (which was zeroed out).

>>studies are to be evaluated by people outside NASA including groups like SSI
>>and individuals like Dr. Andy Cutler (famous NASA cheerleader :-) ).

>Andy agrees with me.

Then why did he ask people to participate in the NASA ourtreach program in
his NSS campaign literature? Why is he wasting his time working on the
outreach program when he thinks the whole thing is a waste? Why did he
tell me in a phone conversation (roughly): "At least they are doing it
[SEI] right this time and taking a few years to study it and not just
jump in".?

>Traxler did the right thing.

You don't even know what he did.

   Allen


-----------------------------------------------------------------------------
| Allen W. Sherzer         |          Death to all extremists!              |
|   [e-mail]            |                                                |
-----------------------------------------------------------------------------

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

Date: 28 Jun 90 04:05:34 GMT
From: zaphod.mps.ohio-state.edu!samsung!emory!emcard!wa4mei!ke4zv![e-mail]  (Gary Coffman)
Subject: Re: NASA announces next steps in Space Exploration Outreach Program (F

In article <[e-mail]> [e-mail] (*Greg*) writes:
>Getting idea's from proper scientwits is the best way to obtain lowcost
>conception.  Corporations, Schools, Groups of Professionals all want to
>achieve space as a reality.  And if *we* get involved, (we = Corporations,
>Private Business, Scientists, (the little guy), *we* will provide answers
>where as other countries are dealing in a certain group.  Plus, think of
>Private Funding!  After all, wasnt the trip that the Mayflower took to reach
>America a *Private* escape?
>
>Was government involved in this?  (Only to stop them).  And when America was
>thriving, England tried to bust up the colonies.  If you remember history
>corectly, we became a nation and are still surviving.  ALL because of 3
>ships which contributed to the making of America.  If you just leave out
>Business and the little guy, you will stifle exploration.  Hinder fundings
>for research  and  allow other governments which are trying to get to the
>moon.. to beat us in inovation.
>

If I remember history correctly, the missions of exploration that gave
Europeans knowledge of the Americas were government funded. Do the
names Columbus and Queen Isobella ring a bell? Before the age of exploration,
Europeans thought that one would fall off the edge of the earth if one
sailed too far westward. We are still early in the age of exploration as
far as space is concerned. The cost of space travel is many orders of
magnitude greater than the cost of three modest sailing ships. No
rational corporation would make an investment of this magnitude without
some assurance of profit. Only after the government funded Lewis and
Clark expedition mapped the interior of this continent did private
settlers risk their lives and fortunes to populate the interior. The
only tools they needed to survive the interior were two strong legs
and an axe. To settle space an entire ecosystem must be carried along
and maintained perfectly. Without solid assurance that a reasonable
opportunity for profit exists in space, there is essentially no chance
that the sums of money needed to mount a real effort in space will be
raised by private sources.

>[Just think a moment]
>What if Russia or Japan or Europe gets a Colony on
>the moon first?  What kind of {sensibilities} will they bring with them?
>What "idealologies" will they include in their view of life?  What kind of
>freedoms?  What kind of beliefs?
>
>The choice is clear.  It cuts into our being.  We must make an effort for
>the Cosmos that captured the hearts of mankind from our beginning.  To
>insure that our future will never forget our ventures.  And make our mark in
>history for the future.
>
>Never leave out the common man.  And the freedom and ideals that are the
>heart of America.  Paid for in blood.
>

The government has the resources to wave the flag and may have the will
to do so. Don't expect private funded efforts to be based on flag waving.
Expect instead that private efforts will be mounted only when profit is
assured.

Gary

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

End of SPACE Digest V11 #588
*******************