Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V13_1/V13_117.ZIP/V13_117

Internet Message Format | 1991-06-28 | 17KB

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson
Received: from hogtown.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/[e-mail] (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests)
          ID </afs/andrew.cmu.edu/usr1/ota/Mailbox/UbfuJki00WBw4Dtk4Q>;
          Wed,  6 Feb 91 01:42:58 -0500 (EST)
Message-ID: <[e-mail]>
Precedence: junk
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Wed,  6 Feb 91 01:42:52 -0500 (EST)
Subject: SPACE Digest V13 #117

SPACE Digest                                     Volume 13 : Issue 117

Today's Topics:
      Information sources for frequent space questions (1 of n)
           Re: The edge of the solar system
       Augustine recommendation for heavylift launcher
           Re: The edge of the solar system
              Re: some questions

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: 1 Feb 91 12:01:42 GMT
From: sdd.hp.com!elroy.jpl.nasa.gov!jarthur!nntp-server.caltech.edu!mustang!data.nas.nasa.gov!amelia![e-mail]  (Eugene N. Miya)
Subject: Information sources for frequent space questions (1 of n)


Many space activies center around large Government or International
Bureaucracies.  In this country that means NASA.  If you have basic
information requests: (e.g., general PR info, research grants, data,
limited tours, and ESPECIALLY SUMMER EMPLOYMENT (typically resumes
should be ready by Jan. 1), etc.), consider contacting the nearest
NASA Center to answer your questions.

EMail typically will not get you any where, computers are used by
investigators, not PR people.  The typical volume of mail per Center is
a multiple of 10,000 letters a day.  Seek the Public Information Office
at one of the below, this is their job:

NASA Headquarters (NASA HQ)
Washington DC 20546

NASA Ames Research Center (ARC)
Moffett Field, CA 94035
[Mountain View, CA, near San Francisco Bay, you know Silicon Valley 8-) ]

NASA Ames Research Center
Dryden Flight Research Facility [DFRF]
P. O. Box 273
Edwards, CA  93523

NASA Goddard Space Flight Center (GSFC)
Greenbelt, MD 20771
[Outside of Washington DC]

NASA Lewis Research Center (LeRC)
21000 Brookpark Rd.
Cleveland, OH 44135

NASA Johnson Manned Space Center (JSC)
Houston, TX 77058

NASA Kennedy Space Flight Center (KSC)
Titusville, FL 32899

NASA Marshall Space Flight Center (MSFC)
Huntsville, AL 35812

NASA Langley Research Center (LaRC)
Hampton, VA 23665
[Near Newport News, VA]

Not a NASA Center, but close enough:
Jet Propulsion Laboratory [JPL/CIT]
California Institute of Technology
4800 Oak Grove Dr.
Pasadena, CA 91109

There are other small facilities, but the above major Centers are set up
to handle public information requests.  They can send you tons of information.

Specific requests for software must go thru COSMIC at the Univ. of Georgia,
NASA's contracted software redistribution service.  You can reach them
at [e-mail].  If this gives you problems, tell me.

NOTE:  Foreign nationals requesting information must go through their
Embassies in Washington DC.  These are facilities of the US Government
and are regarded with some degree of economic sensitivity.
Centers cannot directly return information without high Center approval.
Allow at least 1 month for clearance.  This includes COSMIC.

EUROPEAN SPACE AGENCY        (O) 202/488-4158
955 L'Enfant Plaza S.W., Washington, D.C.  20024

 Arianespace Headquarters
 Boulevard de l'Europe
 B.P. 177
 91006 Evry Cedex
 France

ARIANESPACE, INC. (O) 202/728-9075
1747 Pennsylvania Avenue, NW, Suite 875, Washington, DC  20006

SPOT IMAGE CORPORATION           (FAX) 703/648-1813    (O) 703/620-2200
1857 Preston White Drive, Reston, VA 22091

National Space Development Agency (NASDA), 4-1 Hamamatsu-Cho, 2 Chome
          Minato-Ku, Tokyo 105, Japan

SOYUZKARTA
45 Vologradsij Pr., Moscow 109125, USSR

SPACE COMMERCE CORPORATION (U.S. agent for Soviet launch services)
504 Pluto Drive, Colorado Springs, CO  80906   (O) 719/578-5490
69th flr, Texas Commerce Tower, Houston, TX 77002  (O) 713/227-9000

Additionally information is frequent asked about:
Space camp:

        Alabama Space and Rocket Center
        1 Tranquility Base
        Huntsville, AL 35805
        205-837-3400

    U.S. SPACE CAMP
    6225 Vectorspace Blvd
    Titusville FL  32780
    [phone]
    (registration and mailing list are handled through Huntsville --
     both camps are described in the same brochure)

There is talk of a space camp to be located next to NASA Ames.
Watch that space.

    "It's not a message.  I think it's a warning." -- Ripley

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

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail
Date: 31 Jan 91 18:55:36 GMT
From: van-bc!rsoft!mindlink![e-mail]  (Nick Janow)
Organization: MIND LINK! - British Columbia, Canada
Subject: Re: The edge of the solar system
Sender: [e-mail]
To: [e-mail]


That's a misleading subject line.  It gives the impression that there is a
clearly defined "edge" to the solar system, while in fact any boundaries are
probably very vague.

What defines the "edge"?  Some level of gravity?  Some density of mass?  Some
definitions may have our "edge" overlapping that of several nearby stars.  Who
decides what the definition is?  :)

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

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail
Date: Fri, 1 Feb 91 21:18:25 EST
From: John Roberts <[e-mail]>
Organization: National Institute of Standards and Technology
    formerly National Bureau of Standards
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
To: [e-mail]
Subject: Augustine recommendation for heavylift launcher


>Date: Mon, 21 Jan 91 09:42:30 -0500
>From: "Allen W. Sherzer" <[e-mail]>
>Subject: One Small Step for a Space Activist... (vol 2 no 1)

>                  One Small Step for a Space Activist...
>                                      by
>                            Allen Sherzer & Tim Kyger

>...
>1. New heavy Lift Vehicle (HLV). The Augustine committee advocated reduced
>reliance on the Shuttle and the construction of a new HLV. This could reduce
>costs and free up money for other projects. The current favorite (gets the
>most hype and has strong Senate support) is Shuttle-C or some variant. Shuttle
>C would work but may not be the best choice: other alternatives (Heavy Lift
>Delta and Titan V) may cost less than half as much to develop and operate.
>Activists will need to monitor this to insure that the design meets space
>development goals and not Congressional political goals. Whatever design is
>selected, we also need to insure that the resulting launcher is man rated
>(which is supported by the committee).

>Allen Sherzer: [phone] (work) [phone] (home) [e-mail] (net)
>Tim Kyger: [phone] (work) [phone] (home)

I saw the Augustine Committee's testimony before the US House of
Representatives on C-SPAN:

The Committee laid forth a set of requirements for an expendable launcher
suitable for use in major undertakings such as space station assembly,
Moon/Mars missions, launch of large satellites, etc. Part of its function
would be to take over much or possibly eventually all of the functions
of the current Shuttle. Among the desirable features are lowered cost
per pound, higher reliability, greater ability to launch on schedule,
adaptability to several forms with different abilities, and ability to
be man-rated. It seemed to be understood that the government would help
to finance development, and that the developed boosters would be
manufactured commercially. Because of the importance of expediting
development, these costs would be fairly high, so at least at first
there wouldn't be much saving over continued use of the Shuttle, though
that could change later.  Though the Committee did not specify a
particular design, the two approaches that seemed to receive the most
attention were some variant of ALS or Shuttle-C. The arguments given were
roughly as follows:

Shuttle-C - Many components of the current Shuttle (STS) are used to make
an unmanned vehicle with payload greater than(?) the manned Shuttle.
Because of the heavy use of current technology, development time could be
fairly short - possibly only 4 or 5 years. The Shuttle-C concept can be
expanded somewhat, but not so far as to specify all the goals listed by
the Augustine Committee (i.e. man-rating). There is mention of gradually
phasing in new components, once it's operating, but it is not clear that this
can be done to any great extent.

Advanced Launch System (ALS) - In order to get past the "missile design"
mentality that was the basis for current ELVs, ALS uses a large amount of
new design, with the goal of producing an inexpensive, reliable heavy
launcher. Very wide safety margins and tolerances are used, which reduces
performance slightly compared to a high-performance system such as the
Shuttle, but the reduced need for exhaustive testing, extreme care, etc.
should more than make up for the cost of the additional fuel expended.
With this and a rigid methodology governing payload attachment and launch
techniques, it is hoped that there will eventually be large reductions in
launch costs and in time to prepare and launch. A wide range of configurations
should be available, and human-rating is an eventual possibility.
Estimated time to full implementation and commercial manufacture is
around 8-10 years.

In addition to the Augustine Committee testimony, I heard presentations at
the NIST-hosted conference on reducing the cost of space infrastructure
a year or so back. (That was a good conference - among other things many
launch techniques were discussed, including a good presentation on laser
launchers by Jordin Kare. :-)  For the two launchers in question, the
following additional points were brought up:

  - Shuttle-C is not expected to bring about any per-pound cost savings over
    continued use of the Shuttle, either in the near-term or the far-term -
    the whole intent of the program is to get an increased total national
    payload capacity soon. By contrast, a goal of ALS is to get costs
    down to about $500 per pound of payload to orbit, or about a tenth of
    typical current costs. (Many proposed launchers offer varying savings,
    but this one actually sounds almost plausible, given that such savings
    would not appear right away due to relatively high design costs.)

  - There is some advantage in having a variety of designs in use so that
    the discovery of one flaw does not ground the entire fleet. A problem
    grounding the Shuttle fleet could also ground the Shuttle-C launchers
    because of the many components they have in common.

  - The estimate for launch costs on Shuttle-C not being particularly higher
    than on the Shuttle is based partly on the presumption that the SSMEs
    used (and discarded) on each Shuttle-C flight will be old retired
    engines from Shuttles. (As Henry has said, the SSME is just too expensive
    to burn up brand new ones on expendable launchers.) The result of this
    requirement is that for Shuttle-C to remain "competitive", the regular
    Shuttle must keep flying, and in fact there must be many Shuttle launches
    for each Shuttle-C launch.

  - To allow for various ALS payload requirements, boosters (with diameter
    close to the diameter of the ALS body can be strapped on. Allowed
    configurations include 4 boosters, or 2, or 1 (!) (A vertical rocket
    with a booster on just one side looks very strange - presumably the
    nozzles have to swivel to balance the thrust.)

Congress is going to be debating whether to fund Shuttle-C, ALS, both,
or neither. Funding both may turn out to be too expensive, so it may be
necessary to make a choice. ALS appears to have much greater potential
for the future, but will take a while to get ready. Shuttle-C would be
ready sooner, but it was designed largely with rapid deployment of SDI
hardware in mind, and doesn't offer much beyond an increase in total
national payload capacity, and increased maximum single payload. The
question then seems to be whether getting a new launcher sooner is worth
giving up other possible future benefits.

I would offer the speculation that:
 - SDIO doesn't seem to be planning to launch large quantities of anything
   anytime soon.
 - New projects are unlikely to commit to a new launcher until it has actually
   been built and demonstrated to work. In particular, for a space station
   timetable, waiting around for development of Shuttle-C or ALS would add
   another large delay before the start of construction. It will probably be
   quicker to build a station using existing launchers (Shuttle or expendable)
   or ones which are already far along in development. For tending the
   station after assembly, and for possible expansion, whatever new launchers
   have been developed by that time can be used.

Disclaimers:
 - I haven't said much about the proposed new Delta and Titan launchers
   because I don't know much about them - Allen can provide a lot more
   information. I don't see why several types of launcher couldn't be
   developed and used together - especially if some of them are developed
   either partially or completely with private funding. There are many
   possible market niches for different sizes and types of launchers.

 - My machine may have dropped the automatic Official Disclaimer. Of course
   it applies to all of my messages, whether it is included or not.
     John Roberts
     [e-mail]

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

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail
Date: 1 Feb 91 18:20:50 GMT
From: sdd.hp.com!samsung!rex!rouge![e-mail]  (Fraering Philip)
Organization: Univ. of Southwestern LA, Lafayette
Subject: Re: The edge of the solar system
References: <[e-mail]>
Sender: [e-mail]
To: [e-mail]

In article <[e-mail]> [e-mail] (Paul Blase) writes:

JC>         This is also noted in John Brandt's article on comets
JC>  in "The New Solar System" (228) who discusses Jan Oort's
JC>  conclusion that the "overwhelming majority of comets reside in
JC>  an essentially spherical cloud around the Sun with a radius of
JC>  perhaps 20,000 to 100,000 AU. (By comparison, the nearest srs
JC>  to the solar system, the Alphaha Centauri System, are some
JC>  275,000 AU distant.)"

According to Wednesday's lecture by Dr. Matese, the dominant
characteristic of the Oort cloud is that it is heavily influenced
by the galaxy's tidal pull and the passing of nearby stars.

Comets in the Oort cloud are definately _not_ stable over the lifetime
of the solar system. It is thought that most comets reside in a belt
closer to Neptune called the Kuiper belt.

I don't think Dr. van Oort made the assertion that most comets resided
in the Oort cloud. It is just the major source of short-period comets,
due to the fact that they are easily disturbed from their orbits and
sent down into the inner solar system (or into the outer solar system,
where they come under the gravitational influence of Jupiter or Saturn,
which modifies their trajectory even more...)

Phil Fraering
[e-mail]

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

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail
Date: 30 Jan 91 19:06:20 GMT
From: sdd.hp.com!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!pitt!nss![e-mail]  (Paul Blase)
Organization: The NSS BBS, Pittsburgh PA [phone]
Subject: Re: some questions
Sender: [e-mail]
To: [e-mail]

>> 3) Which are the Pioneers/Voyagers that have left the Solar
>> Syatem?

 CC> The ones that passed the "Last Chance Saloon", just beyond
 CC> Pluto!

 CC> Seriously, how do you define "the Solar System".  There is a
 CC> plausible basis for saying that when you cross the heliopause,
 CC> you have "left the Solar System", but I don't believe any have
 CC> done so yet. --

the edge of the solar system is more-or less defined as the outermost
planet (currently Neptune, I believe).  One of the things that the
Voyager probes are looking for now is the heliopause.

--- via Silver Xpress V2.26 [NR]
--
Paul Blase - via FidoNet node 1:129/104
UUCP: ...!pitt!nss!Paul.Blase
INTERNET: [e-mail]

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

End of SPACE Digest V13 #117
*******************