Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V09_3/V9_389.ZIP/V9_389

Internet Message Format | 1991-07-08 | 20KB

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson
Received: from holmes.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr1/ota/space/[e-mail] (->+dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl) (->ota+space.digests)
          ID </afs/andrew.cmu.edu/usr1/ota/Mailbox/QYINFky00UkZ4MKE4b>;
          Sun, 23 Apr 89 05:16:32 -0400 (EDT)
Message-ID: <[e-mail]>
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Sun, 23 Apr 89 05:16:24 -0400 (EDT)
Subject: SPACE Digest V9 #389

SPACE Digest                                      Volume 9 : Issue 389

Today's Topics:
        Phobos II failure analysis - hit near Phobos?
     Mobile satellite system proven in airborne test (Forwarded)
          Re: Is 'better than gravity assist' used?
    Re: URGENT -- SPACE STATION FUNDING VOTE ON TUESDAY!!
          Re: Is 'better than gravity assist' used?
         Re: US citizen - ET contact legal penalties
         Hardened chips...   Rest of message.
    Re: Soviet Launch Sites (was Re: space news from Jan 16 AW&ST)
NASA to support commercial development sounding rocket flights (Forwarded)
----------------------------------------------------------------------

Date: Sun, 23 Apr 89 02:42:59 EDT
From: Glenn Chapman <[e-mail]>
To: [e-mail], [e-mail],
        [e-mail]
Subject: Phobos II failure analysis - hit near Phobos?

    The USSR has declared the Phobos II probe dead in orbit according to
Radio Moscow (Apr. 18/19).  A commission has been set up to study the
failure, but some information is now available.  On Mar. 27th at 3:59 p.m.
Moscow Time (7:59 am EDT) the probe was ordered to turn towards the Phobos
for almost the final picture set.  Phobos II, which does not have its
antenna mounted on a separate pointing platform, was to turn back to the
Earth for signal transmission by 6:59 - 7:05 p.m. (AW&ST Apr. 17) However,
no radio source was at time on earth, though at 8:50 p.m. they regained the
signal for 13 min.  Indications are that it was not a transmitter failure
as was first thought, though this is the backup 5 Watt radio, not the
main 50 Watt one which failed in January.  Instead, in an interview with
Roald Segdeev (former director of the Institute for Cosmic Research (IKI)),
it was revealed that the probe has been found to be rotating unexpectedly.
The Russians suggest the probe probably collided with something near
Phobos, either particles in orbit near the moon, or possibly debris from
the separated main propulsion section (suggested by Jonathan McDowell at
Harvard).  Another possibility not mentioned by the Soviets was simply a
hydrazine thruster failed (either stuck on or off).  They are worried
that the probe may crash onto the Martian moon as this current orbit
is unstable, according to James Oberg (Soviet Aerospace Apr. 3).
   A latter short wave report stated that the Phobos II mission had
achieved 75% of the intended studies of Mars.  The probe
made excellent studies of the Martian magnetic field, the plasma
density around the planet and infrared observations of the surface.
However, originally it was to stay in the original orbit with a
closest approach to the planet of 800 Km. (500 mi.) for 25 days,
but only 14 days were spent before the orbit was raised to 6300 Km
(3940 mi.)  This considerably reduced the accuracy of Mars observations.
The probe did obtain pictures of Phobos from less than 100 Km (63 mi.) much
closer than the Viking orbiter did at 480 Km (300 mi.).  The Soviets
claim these are the best photos so far of the Martian moon.  There is
some uncertainty in this as Viking had better cameras, but clearly
Phobos II took more pictures.  In all the probe obviously obtained much data,
but probably it not three-quarters of the original planned mission.
Never the less, this was the most successful of the USSR's Mars
missions.
   Indications are that the Russians are considering using the ground
test vehicle as a full system and launching it for a duplicate mission
in 1992.  The next two launch windows open in Sept. 1990 and Oct. 1992.
Unfortunately, 1988 was the best launch window until 2001 (taking the
least energy).  Probably they would have to use what is called a type II
Hohmann transfer orbit, which is slower but takes less energy just to
be able to run a similar mission.  Skipping the 1990 mission probably
is necessary just to do the checkout of this craft, and to do the
programming to prevent the problems that killed the Phobos I probe
in Sept. '88.
   As Groucho Marx used to say "Close but no cigar" for this Soviet
Mars mission.

                                                Glenn Chapman
                                                MIT Lincoln Lab

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

Date: 21 Apr 89 16:40:36 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Mobile satellite system proven in airborne test (Forwarded)

Paula Cleggett-Haleim
Headquarters, Washington, D.C.                     April 20, 1989

Franklin O'Donnell
Jet Propulsion Laboratory, Pasadena, Calif.


RELEASE:  89-56

MOBILE SATELLITE SYSTEM PROVEN IN AIRBORNE TEST


     A two-way digital voice terminal for land, aeronautical or
maritime mobile communications has been demonstrated in the field
for the first time by researchers from NASA's Jet Propulsion
Laboratory, Pasadena, Calif.

     The trial, which took place in late March 1989, is believed
to be the first-ever field test of a state-of-the-art, low-bit-
rate voice coder over an on-orbit satellite in a commercial
application.

     During the tests, researchers used a voice terminal on a
Boeing 727 to communicate with a ground station in Southbury,
Conn.  The jet, based out of Atlantic City, N.J., was airborne
over the eastern U.S. seaboard during the tests.  Signals were
relayed between the plane and ground by an orbiting satellite
operated by the International Maritime Satellite (Inmarsat)
organization.

     "The system we demonstrated is a type that would be
beneficial for planes in transit over the Atlantic Ocean," said
Dr. William Rafferty, manager of JPL's Communications Section,
which conducts the Mobile Satellite Experiment (MSAT-X) program
for NASA.

     Planes flying over the Atlantic currently must relay
communications at times through other planes on the ocean
route.  A mobile satellite communication system would link each
plane to ground stations via satellite.

     The terminal system demonstrated during the test uses a 4.8-
kilobit-per-second digital voice system developed at JPL.
Advanced digital modulation and coding techniques are used to
achieve a highly efficient channel bandwidth of 5 kilohertz.

     Under the MSAT-X program, JPL has been developing
technologies that would be useful in mobile satellite systems.
Areas of research include mechanically and electronically steered
vehicle antennas, modulation encoding and networking methods.

     A fully developed mobile system would use satellites to
extend mobile telephone services to remote ground users and to
users in the air and on the sea who cannot be served by cellular
telephone systems.

     In addition to planes and ships, such a system also could
serve such users as private drivers, cross-country trucks,
forestry personnel and law-enforcement agents.

     JPL's role is strictly to develop new technologies required
for a mobile satellite system.  NASA plans to seek cooperative
agreements with the commercial operator of a first-generation
satellite system whereby the space agency will launch the first
satellite.  In exchange, NASA would be able to conduct technology
validation experiments using a small percentage of the
satellite's capacity for the first 2 years of operation.

     Rafferty said plans call for an MSAT-X land mobile
experiment in Australia during July 1989.  The location of that
test will make use of a favorably situated on-orbit satellite.

     The March test was made possible through the cooperation of
the Federal Aviation Administration, which operates the Boeing
727 research jet used in the experiment.  Inmarsat and its U.S.
signatory, Comsat Inc., provided ground facilities.

     MSAT-X is funded by the Communications and Information
Systems Division of NASA's Office of Space Science and
Applications.

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

Date: 20 Apr 89 19:03:52 GMT
From: jarthur![e-mail]  (John H. Kim)
Subject: Re: Is 'better than gravity assist' used?

In article <[e-mail]> [e-mail] (Kristian Wedberg) writes:
>Gravity assist has been used many times, by the Voyager-probes for instance.
>The way I understand it, however, is that if you use a part of your fuel
>just when you swing by the moon/planet/sun, you can reach a higher
>velocity than if you use it all up when you start the voyage.
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Don't you mean "than if you didn't use any of your fuel"?

You can achieve velocities higher than possible with your fuel with
simple gravity assist.

I don't think this would be used even if it is possible (I think it is).
Planetary scientists seem to be very patient (how many years has it been
since the voyagers were launched?) so I don't think they'd mind waiting
a few more months to save a little fuel.  Remember, you have all the
time in the world (or at least all the time in the radioactive power
source) but only so much fuel.  The only reasons I could see for this
are:

1) Your flyby of a planet and its moons requires you to use your fuel
   in order to get to the next planet.  The goal of this would be more
   for adjusting your trajectory than trying to increase velocity.

2) You're going to pass the last planet and you want to set a new speed
   record for a manmade object in contact with the earth :-)  Or you
   just might want the higher velocity to study something.

3) You have an emergency which requires all this velocity.

Hmm, I suppose number (1) would be okay if you felt using your fuel was
worth getting there a little earlier.

btw, how did this message get from Sweden to California in one day?
--
John H. Kim                 | (This space to be filled when I
[e-mail] | think of something very clever
uunet!muddcs!jarthur!jokim  | to use as a disclaimer)

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

Date: 22 Apr 89 00:13:24 GMT
From: umigw![e-mail]  (steve emmerson)
Subject: Re: URGENT -- SPACE STATION FUNDING VOTE ON TUESDAY!!

In article <[e-mail]> [e-mail]
(John McKernan) writes:
>So we're pretty much stuck with that [refering to the government's and
NASA'S] efficiency.

Agreed.  Our efforts to influence the space program by trying to influence
congress make me think of *indirect* Brownian motion --- if such a thing
exists :-).
--
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: 21 Apr 89 20:24:00 GMT
From: sco![e-mail]  (The little bug on your shoulder)
Subject: Re: Is 'better than gravity assist' used?

In article <[e-mail]> [e-mail] (Kristian Wedberg) writes:
>Gravity assist has been used many times, by the Voyager-probes for instance.
>The way I understand it, however, is that if you use a part of your fuel
>just when you swing by the moon/planet/sun, you can reach a higher
>velocity than if you use it all up when you start the voyage.
>
>Is this so and has it been used, or did I break something in the energy-laws?
>
>
>    -kitte


    Well, I'm not exactly sure about using a burst of fuel while
moving thru the gravity well, but I do know that the vehicle is tapping
the gravitational potential energy of the planet (oh, I can just here the
ecologists now - "just think of the irreparable harm of draining a planet's
energy"). Think of it like a basketball that rolls along the rim of a basket,
and emerges with more momentum than it hit the basket with (another image
of ecologists attempting to get basketball banned because of what its doing
to the planet ;)).

    I remember once seeing a plan in which a starship would potential energy
of a binary system, where one of the stars is a white dwarf. Kinda neat,
and accelerates you by 1/30th the speed of light (zoom!).


Joe DiLellio <"Can I color in the whites of your eyes & staple your lips shut?">
...!uunet!sco!joed         New    E-mail   Old       ...!ucbvax!ucscf!oprjcd
[e-mail]          <--Paths  Addresses  Paths-->    [e-mail]
...!spl1!sco!joed [My opinions. Mine mine mine, hahahaha!]  [e-mail]

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

Date: 20 Apr 89 17:39:32 GMT
From: portal!atari!daisy![e-mail]  (Mike Wooding)
Subject: Re: US citizen - ET contact legal penalties

In article <[e-mail]>, [e-mail] (Larry Lippman) writes:
>     I find it somewhat difficult to believe, however, that the cited
> CFR section "can impose an indefinite quarantine which cannot be broken,
> even by court order."  Any law is subject to judicial review, and it is
> clearly unconstitutional to create a law which could not be subject to
> judicial review or otherwise mitigated by "court order".  In general,
> any detention pursuant to law of a living person (under the circumstances
> I have to add this "qualifier") can be subject to judicial review through
> a special proceeding of habeas corpus (or possibly mandamus, depending upon
> the circumstances).

 I hate to obfuscate these legal issues, but the premise that "Any law is
 subject to judicial review" is not at all clear (at least to me). E.g see
 Article III, section 2, 3rd paragraph: [Supreme Court has jurisdiction]
 "with such Exceptions, and under such Regulations as the Congress shall
 make." My reading of this is that the Constitution itself explicitly
 provides Congress with the power to exclude the jurisdiction of the
 courts. So, if you cavort with ETs ... :-)

 m wooding

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

X-Delivery-Notice:  SMTP MAIL FROM does not correspond to sender.
Date:     Fri, 21 Apr 89 17:18:07 -0900
Reply-To: <[e-mail]>
Sender: <[e-mail]>
From: ROBERT J HALE                    <[e-mail]>
Subject:  Hardened chips...   Rest of message.

Sorry about that.  The mailer decided to send the message and I can't kill
it once it has hit the net.   I would like to know if there is a generic
way one hardens the chips.  Can I harden my own chips, (not likly).  Where
can I buy hardened chips.   What is the percentage cost increase (percentage)
for a chip hardened over not hardened.   Thanks.

                                    Robert J. Hale III
                                    FNRJH@ALASKA
                                    ISECCo  Director.

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

Date: 21 Apr 89 12:18:41 GMT
From: mcvax!kth!sunic!ericom!kk36.ericsson.se![e-mail]  (Bj|rn Fahller TT/MLG)
Subject: Re: Soviet Launch Sites (was Re: space news from Jan 16 AW&ST)

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Glen Overby) writes:
>>If I recall correctly what was said in James Oberg's _Red Star in Orbit_,
>>the city of Baikonur doesn't even exist!  It was a cover-up...
>>
>>Now my question: where is the true place that the Soviet shuttle (and other
>>space shots) is launched from?
>
>The Baikonur Cosmodrome.  That is its official name.  The name is indeed
>a relic of a deception attempt, since the town of Baikonur -- which does
>exist -- is far away and has nothing to do with the Cosmodrome.
>
>>I seem to recall hearing one time about two locations.
>
>The other major Soviet launch site is Plesetsk; the traffic is split
>about 50-50.  Plesetsk is primarily military and has been very highly
>secret until quite recently.

Secret until how recently? In northern Sweden, where I come from, Rocket
launces from the Pletetsk base (Not more than 300kms from the Swedish border),
have been seen at night time for quite a few years now.


---------------------------------------------------------------\_
SNAIL: Bjoern Fahller           Vox humana:  (+46) 8 - 719 62 52 \_
       ERICSSON TELECOM         Fax machina: (+46) 8 - 740 28 34_/
       Dept. KK/ETX/TT/MLG    ,--------------------------------/
       S-126 25 STOCKHOLM   ,/        "The more you know,
       SWEDEN             ,/           the better you realize
-------------------------/             how little you know"
Please DO comment on my language.

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

Date: 21 Apr 89 16:42:37 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA to support commercial development sounding rocket flights (Forwarded)

Jim Ball
Headquarters, Washington, D.C.                   April 21, 1989

RELEASE:  89-58

NASA TO SUPPORT COMMERCIAL DEVELOPMENT SOUNDING ROCKET FLIGHTS


     The National Aeronautics and Space Administration (NASA)
announced today support for a series of commercial sounding
rocket flights that will provide opportunities for the
exploration of industrial space applications by NASA-sponsored
Centers for Commercial Development of Space (CCDS).

     Following the successful flight of Consort 1, a package of
materials science investigations launched March 29 atop a
commercially-provided rocket at White Sands Missile Range, N.M.,
NASA's Office of Commercial Programs has decided to extend
funding support for a series of similar flights.

     NASA will provide funds to help support the costs of payload
development and launch services for two additional sounding
rocket flights in FY 1990 and is planning to support from two to
four flights annually thereafter depending on requirements.

     The Consort 1 mission was conceived and managed by the
Consortium for Materials Development in Space at the University
of Alabama-Huntsville (UAH).  The mission represented a pilot
project in which $1.4 million in NASA grant monies, provided to
the UAH Center for Commercial Development, financed the purchase
of commercial launch services and payload integration.

     "This experiment in private sector space operations worked
marvelously," said James T. Rose, NASA assistant administrator
for commercial programs.  "The launch was a first for the U.S.
commercial space transportation industry, proving that a private
provider can efficiently serve the requirements of a commercial
user with a minimum of government involvement."

     Follow-on, sounding rocket flights will be procured and
managed by the UAH CCDS, who also will integrate and prepare for
flight the payload investigations conceived and developed by
participating CCDS and their industry partners.

     NASA's Office of Commercial Programs, Washington, D.C.,
created in 1984 to provide a focus for efforts to encourage
greater private sector involvement and investment in the nation's
civil space program, is responsible for the establishment and
management of the 16 CCDS.

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

End of SPACE Digest V9 #389
*******************