Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v16_6/v16no648.txt

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Date: Sun, 30 May 93 04:59:59
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #648
To: Space Digest Readers
Precedence: bulk


Space Digest                Sun, 30 May 93       Volume 16 : Issue 648

Today's Topics:
Comet Shoemaker-Levy, Possible Collision With Jupiter in 1994 (4 msgs)
                        Hey sherz! (for real!
                        Launch Vehicle Permits
                Liberal President murders spaceflight?
                      Magellan Update - 05/28/93
                         Mining on the Moon?
                         Moon vs other bodies
                          non-solar planets
                            Sagan / TAPPS
                 Space Marketing would be wonderfull.
           Tom Wolfe's THE RIGHT STUFF - Truth or Fiction?
Voyager Discovers the First Direct Evidence of the Heliopause (2 msgs)
                              VOYAGER II
         What's up with Motorola's Iridium project? (2 msgs)
                   Why a far side Science station.

    Welcome to the Space Digest!!  Please send your messages to
    "[e-mail]", and (un)subscription requests of the form
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    (THENET), or [e-mail] (Internet).
----------------------------------------------------------------------

Date: 29 May 93 18:38:56 GMT
From: Pat <[e-mail]>
Subject: Comet Shoemaker-Levy, Possible Collision With Jupiter in 1994
Newsgroups: sci.space,sci.astro

Steinn remarks on the possible trajectories of S/L.

Has any one done the modeling for the comet instead  hitting
the edges of atmosphere and doing a massive aero-braking
manuever?

what would we get then?  20 more moons?

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

Date: Sat, 29 May 1993 23:16:24 GMT
From: "Phil G. Fraering" <[e-mail]>
Subject: Comet Shoemaker-Levy, Possible Collision With Jupiter in 1994
Newsgroups: sci.space,sci.astro

[e-mail] (Pat) writes:


>Steinn remarks on the possible trajectories of S/L.

>Has any one done the modeling for the comet instead  hitting
>the edges of atmosphere and doing a massive aero-braking
>manuever?

>what would we get then?  20 more moons?

Assuming it survived the first past it would then have to deal with
the second, unless pertubations caused by the galilean satellites
raised the perijove out of the atmosphere (which is rather unlikely).

Unless it passes _close_ to one of said moons, any influence by them
(although WARNING: THIS IS JUST A GUESS.  IT IS ONLY A GUESS. PLEASE
DO NOT TAKE EXTREMELY SERIOUSLY) would merely result in the line of
node of the orbit (assuming the orbit was the traditional kind and not
a 'temporary' one) being rotated.

Any questions?

--

+-----------------------+---------------------------------------+
|Phil Fraering          | "...drag them, kicking and screaming, |
|[e-mail] | into the Century of the Fruitbat."    |
+-----------------------+-Terry Pratchett, _Reaper Man_---------+

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

Date: Sat, 29 May 1993 23:05:05 GMT
From: Henry Spencer <[e-mail]>
Subject: Comet Shoemaker-Levy, Possible Collision With Jupiter in 1994
Newsgroups: sci.space,sci.astro

In article <1u8ak0$[e-mail]> [e-mail] (Pat) writes:
>Has any one done the modeling for the comet instead  hitting
>the edges of atmosphere and doing a massive aero-braking
>manuever?
>
>what would we get then?  20 more moons?

No, you get a somewhat more drawn-out, sort of episodic, Jupiter impact.
Aerobraking *alone* can't get you into a stable orbit.  The orbit always
passes through the point where it was last changed, so, in particular,
the post-aerobraking orbit always intersects the atmosphere.

In any case, a fragile object like a comet (or piece of same) is most
unlikely to survive the first pass intact.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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

Date: 30 May 93 06:08:09 GMT
From: Leigh Palmer <[e-mail]>
Subject: Comet Shoemaker-Levy, Possible Collision With Jupiter in 1994
Newsgroups: sci.space,sci.astro

In article <[e-mail]> Henry Spencer,
[e-mail] writes:
>In article <1u8ak0$[e-mail]> [e-mail] (Pat)
writes:
>>Has any one done the modeling for the comet instead  hitting
>>the edges of atmosphere and doing a massive aero-braking
>>manuever?
>>
>>what would we get then?  20 more moons?
>
>No, you get a somewhat more drawn-out, sort of episodic, Jupiter impact.
>Aerobraking *alone* can't get you into a stable orbit.  The orbit always
>passes through the point where it was last changed, so, in particular,
>the post-aerobraking orbit always intersects the atmosphere.

While this is true for a two-body interaction, the orbit in question is
strongly influenced by a third body, the sun. For such marginally bound
orbits it is not yet possible to say they are "stable" in any strict
sense. It is also quite conceivable that interaction with the sun could
raise the perijove on a succeeding pass, leaving the comet in a more
strongly bound orbit after the aerobraking. Under these circumstances
the comet will not pass though the point (with respect to Jupiter) where
its orbit was last changed.

Leigh

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

Date: 28 May 93 22:50:00 GMT
From: Kevin Bauer <[e-mail]>
Subject: Hey sherz! (for real!
Newsgroups: sci.space

-=> Quoting Matthew Deluca to All <=-

MD> .@SUBJECT:Re: Hey Sherz! (For real!) Cost of LEO
MD> N .@FROM   :[e-mail]
MD> N .@MSGID  :<[e-mail]>
MD> N From: [e-mail] (Matthew DeLuca)
MD> Newsgroups: sci.space
MD> Subject: Re: Hey Sherz! (For real!) Cost of LEO
MD> Date: 25 May 1993 10:30:28 -0400
MD> Organization: The Dorsai Grey Captains
MD> Message-ID: <[e-mail]>

MD> In article <[e-mail]> [e-mail] (Henry
MD> Spencer) writes:
>Why do you assume these things require the shuttle?  The most elaborate
>in-space repair/salvage operations yet done -- Salyut 7 and Skylab --
>did not use the shuttle.

MD> For shame.  Docking with a controlled space station with autonomous
MD> life  support capabilities and tinkering with it is in no way
MD> comparable to working on a free-flying satellite that is in no way
MD> cooperating with you.  99.99% of the hardware up there that we could
MD> conceivably want to service can be done far more easily and effectively
MD> from the shuttle.
MD> (And before anyone points out that it is far cheaper in most cases to
MD> launch  a replacement than to fund a shuttle flight to fix it: yes, but
MD> that's not the point here.  We're talking about what can be done
MD> *assuming* you are going to fix the thing in the first place.)
MD> --
MD> Matthew DeLuca
MD> Georgia Institute of Technology, Atlanta Georgia, 30332
MD> uucp:        ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!matthew
MD> Internet: [e-mail]

For Shame. The following are excerpts of an interview with former astronaut
Pete Conrad from the June/93 issue of Final Frontier.

"FF: What did you think of your chances when your first got up there?"
(To Skylab)

"Conrad: No idea. And things kept getting worse. The more we ran the
electrical equipment, the more it overloaded the electrical capability of
batteries and the ATM [Apollo Telescope Mount] solar panels. For the first
four or five days I wasn't sure we were going to make it."

"FF: You and Paul Weitz deployed the sunshield, which took care of the
heating problem. Then, on Mission Day 14, you and Joseph Kerwin went
after the electrical problem. Is that when you deployed the solar wing?"

"Conrad: The solar wing weighed around a ton, so it had a hydraulic snubber
that would slow it down so that it would lock nice and gently. But the
snubber wasn't heated. It didn't need any heat because it was supposed to
work right after it went into orbit. By this time we knew it would be
frozen and that we would have to break it.
We had a rope hooked up to pull the array free but, at the beginning,
we weren't getting anywhere very fast. Finally, we got it anchored on the
ATM structure. I went out on the wing and figured if Kerwin could get it
as absolutely tight as possible-while I stood out there about the hinge
line and pushed the rope up-I could break the array free. What I didn't
realize was that I was making myself like a bow and arrow, and when the
panel broke free I went flying out."

"FF: Tumbling into space?"

"Conrad: Oh, yeah. I let go of the rope and wound up at the end of my
umbilical line out in the middle of nowhere."

I'm sorry Mr. DeLuca but I think compared to Skylab's problems Intelsat
was a much less risky mission. Not easy but, definitely not as difficult.
I'm sorry I don't have an Internet address for you to respond to but I
don't really know how to use this e-mail system real well just yet.
Sincerely,
Kevin Bauer


... NewsFlash: Energizer Bunny goes beserk, charged with battery.
--- Blue Wave/QWK v2.10

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

Date: Sat, 29 May 1993 23:29:50 GMT
From: Henry Spencer <[e-mail]>
Subject: Launch Vehicle Permits
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (SNYDER GARY EDWIN JR) writes:
>Looking through "Space Mission analysis and Design" I saw that OCST is
>the single point contact for all commercial expendable vehicles. My
>question is what about non-expendable. My hp rocket was really
>expensive, not to mention the GPS,hamradio,packet, and cpu payload.
>This thing is not expendable

If it still looks a lot like an expendable rocket, you're going to have
a hard time convincing OCST that they *don't* have jurisdiction.  The
intent was that they have jurisdiction over all non-government space
launches.  I'm not sure the word "expendable" actually appears in the
enabling legislation, for that matter.

>    ... How about a
>really high flying sailplane with pressure suit and long burning, boost
>motor?

Well now, that's an interesting case.  OCST does *not* have jurisdiction
over aircraft.  Even rocket-powered aircraft.  Even very-high-performance
rocket-powered aircraft.  And the FAA rules for experimental aircraft are
not cumbersome; Gary Hudson's comment (at Making Orbit) was, roughly, "you
need more paperwork to build a house than to build an experimental aircraft".

Now mind you, to convince everyone that your bird is an aircraft, it'll
have to resemble one.  That means wings.  It also, almost certainly, means
an on-board pilot.  It certainly means a long, systematic test program
"expanding the envelope" before you try for orbit.

Bear in mind that there are still some complications along the way.  Like,
for example, you need special high-level FAA approval to fly supersonic
over US territory.

>    How do you get around the bureaucracy?

You can't, really.  What you *can* do is pick the part of the bureaucracy
that you prefer dealing with -- say, the FAA -- and set up your project so
it's in their territory.  Then *they* will fend off the folks you don't
want involved, with luck.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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

Date: Sat, 29 May 1993 13:34:40 GMT
From: "Phil G. Fraering" <[e-mail]>
Subject: Liberal President murders spaceflight?
Newsgroups: sci.space

[e-mail] (Greg Mccrory)  writes:


>On 27 May 1993 22:36:59 [e-mail] (Phil G. Fraering) wrote:
>> 1. If they're not economically viable, then _WHY_ did they need
>> to be outlawed (fuel reprocessing)?

>Because they generate too much hazardous waste, making the risks
>far outweigh the benefits.

I was talking about fuel reprocessing, not breeders.

Reprocessing takes the more hazardous materials out of fuel rods,
greatly _reducing_ the amount of material that needs to be treated
as high-level radioactive waste.

By banning reprocessing, the amount of waste is increaced. And it's
not in rad waste storage areas. It's on abandoned railroad track probably
very close to your house.

>> 2. Banning fuel reprocessing while at the same time more stringent
>> waste disposal requirements are being made is a de-facto limitation
>> to the point of banning nuclear power........................

>What would you have us do, dump it all over the place and
>contaminate everything for thousands of years?!  It's a good
>thing we had those restrictions or we'd be in the same sorry
>shape as Russia today!

[Eek! I just showed that Phil is one of those evil nasty polluters
who wants to mutate everyone...]

It's disingenuous to pass laws that say that

1. Waste can't be recycled and reduced in volume

2. Something must be done with it.

while

3. Every proposed storage site needs 50 years of bureaucratic review
before startup.

With a ban on recycling, and a virtual ban on safe disposal, and a final
ban on plants that *don't* recycle or dispose, is a defacto ban on
nuclear power without any of the political fallout of a ban on nuclear
power.

Finally: have you thought that your limitations on recycling are going
to cause some nasty accidents in the U.S. someday? It's creating a situation
similar to the one that caused the accident in the Urals that some think
was as bad as Chernobyl.

>> .................................... And it worked: noone's started
>> construction on a new plant in years and years.

>Thank God!

E-mail me when you're interested in really talking about it instead
of creating the straw man that Phil wants to destroy the Earth.

Until then, you're in my kill file. I would advise everyone else to do
the same.

(And you know, you accomplished quite a feat in achieving this since
I found some decaf that tastes just as good!)

>/=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-\
>| Greg McCrory  *  Metairie, LA  *  [e-mail] |
>\=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-/

>* JABBER v1.2 *

>----
>The Ozone Hole BBS * SKYDIVE New Orleans! * [phone] * V.32bis/HST
--

+-----------------------+---------------------------------------+
|Phil Fraering          | "...drag them, kicking and screaming, |
|[e-mail] | into the Century of the Fruitbat."    |
+-----------------------+-Terry Pratchett, _Reaper Man_---------+

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

Date: 29 May 93 18:34:40 GMT
From: Pat <[e-mail]>
Subject: Magellan Update - 05/28/93
Newsgroups: sci.space,sci.astro,alt.sci.planetary

One big round of applause for all the success so far!!!


So what was the data coding error that caused magellan to go through
2? passes with the wrong attitude?

What exactly happened?  and I thought the system was designed
to check all data before sending?  is the TEX, so different that
all attitude commands are "Out of SPec"  for the checking system?

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

Date: Sat, 29 May 1993 23:16:19 GMT
From: Henry Spencer <[e-mail]>
Subject: Mining on the Moon?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>Has anyone read Heinlen's "The moon is a harse Mistress"

Lots of us.

>... catapult is used to sling large loads of ore surrounded by
>a metal jacket with braking thrusters to Earth. Is this a practical option -
>can it be done and if so would it be to expensive?

Feasibility of that *exact* scheme is doubtful.  Heinlein's catapult was
a linear induction motor, which was why the projectile just needed a metal
jacket.  Unfortunately, induction motors do not scale up well.  A large
catapult would almost certainly be a linear synchronous motor, which needs
coils on the projectile (although the coils can be separated from the
payload and decelerated again, yielding O'Neill's mass driver).

More generally, there is no doubt that you could build a lunar catapult
capable of launching large masses into an Earth-impact trajectory.  Slowing
them down at the Earth end will not be quite as easy as Heinlein suggested,
mind you.

The major question is whether it's worth the bother.  There is nothing
known to be abundant on the Moon that is so scarce on Earth as to be worth
the expense of setting up such a system.  Rational lunar mining will be
aimed at customers on the lunar surface and in space, and even the in-space
market will be quite vulnerable to reductions in Earth launch costs and
appearance of alternate suppliers exploiting asteroids etc.

>- what are the type and extent of the mineral resources on the moon?

Essentially nothing is known about this.  Ore deposits are, almost by
definition, rare events -- the results of extreme conditions.  We have
a sketchy knowledge of the Moon's average geology (quite sketchy -- every
Apollo mission found new minerals), but essentially no data on extremes.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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

Date: Sun, 30 May 1993 00:29:36 GMT
From: Henry Spencer <[e-mail]>
Subject: Moon vs other bodies
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Tom) writes:
>>>>Commercial justification for a return to the Moon is slim, but for
>>>anything else -- Mars, asteroids, etc. -- it's nil.
>>>... this seems a little premature...
>>Certainly.  But we're talking about justifications *now*, not ones that
>>might perhaps possibly come into existence *after* considerable further
>>exploration.
>
>...Wouldn't potential investors like to learn of the other possibilities,
>relatively cheaply, before committing big bucks to operations? ...

You're assuming that they're planning to commit to operations.  The answer
from potential investors on *all* these projects is "forget it until you
can show us some committed customers".

The Moon has some real advantages:  the outlines of its geology are
known, it's close enough for teleoperation, transit times are short and
communication is easy, and it has enough gravity that you don't have
to reinvent all the technology.  Only the first of these can be removed
by exploration of other bodies, and only with quite heavy investment.
(Flybys are easy, but they don't tell you important things like "how
firm is the regolith?".  Acquiring Apollo-level knowledge of other
bodies will not be quick or cheap, especially if manned missions are
impractical -- which they are at the moment.)
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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

Date: Sun, 30 May 1993 00:16:49 GMT
From: Henry Spencer <[e-mail]>
Subject: non-solar planets
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Victor Laking) writes:
>With all this recent discussion about planets around other stars, I
>wouldn't mind it if someone could give some info about what HAS been
>discovered instead of just methods to do so.

IRAS found dust disks around a number of nearby stars, including Vega
and Beta Pictoris.  The one around Beta Pictoris has been imaged.  These
disks are pretty big, and there *might* be planets closer in.  Recent
work studying the exact infrared spectrum of the disks has found some
evidence for this.  (The closer you get to the star, the warmer the
dust gets.  If the overall spectrum seems to be missing the emissions
that would be expected from the dust at one particular distance, the
obvious cause is that there's something big at that distance which has
swept up the nearby dust.)

The classical technique for detecting extra-solar planets -- very precise
measurements of the position of the star over many years, to find the
slight deviation from straight-line motion caused by a planet -- is
fraught with problems and nobody has achieved undisputed positive
results that way.

A modern variation on this is ultra-high-accuracy spectrometry, looking
for the changing Doppler shifts caused by those motions.  This has yielded
a number of tentative hits, but observation over a decade or two is going
to be needed to confirm them.  (Such techniques find only the biggest
planets, e.g. Jupiter-sized, and their orbital periods are typically
at least several years because they can't form too close to the star.
You need to track the motion over at least one orbital period and
preferably more before it really looks convincing.)

The only extra-solar planets whose existence is beyond dispute are one
or two around pulsars, where the Doppler shifts can be measured very
accurately and the orbital periods are short.  They're very far away
and there is no prospect of direct observation.  They're also, last
I heard, somewhat puzzling -- the supernova that produces the pulsar
should blow them away.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

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

Date: Sat, 29 May 93 14:11:02 EET
From: [e-mail] (F.Baube[tm])
Subject: Sagan / TAPPS

From: "John F. Woods" <[e-mail]>
> Subject: Why is everyone picking on Carl Sagan?
>
> this, then, was used to trumpet the fact that nuclear war is bad
> (OK, folks, hands up -- how many in the audience here were saying
> to themselves, "Gee, I thought nuclear war was a splendid idea
> until TAPPS proved their nuclear winter idea!").

Well, don't forget that there were psychopathic
statements from the Pentagon brass like
"In the event of nuclear war, just lay a door over
a hole in the ground and shovel some dirt over it."
I believe this was said in testimony to Congress.

    Duck and Cover !

--
* Fred Baube (tm)    * "Government had broken down.
* [e-mail]  *  I found the experience invigorating."
* 60 28' N  22 18' E *  -- Maurice Grimaud, Paris prefect of
* #include <disclaimer.h>                 police in May 1968

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

Date: Sun, 30 May 1993 00:31:14 GMT
From: bill nelson <[e-mail]>
Subject: Space Marketing would be wonderfull.
Newsgroups: sci.environment,misc.consumers,sci.astro,talk.environment,talk.politics.space,sci.space

[e-mail] (Gary Coffman) writes:
: In article <[e-mail]> [e-mail] (bill nelson) writes:
: >
: >Unfortunately, the only place highway billboards have gone away is where
: >they have been legislated out of existance. Even then, the advertisers
: >try to find ways around the bans.
:
: I miss the Burma Shave signs. They broke the monotony of long trips
: between interminable boring stretches of featureless pine forests.
: No more counting the "See Rock City" signs, no more "Visit the Jungle"
: signs. The highways are now bland and boring affairs crawling along
: under artificially reduced speed limits. Now we are reduced to playing
: trolling for tailights with our radar detector testers to stay alert.
:

Yeah - I miss the Burma Shave signs, also. They were small and discrete,
not large monsterous pictures.

Bill

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

Date: Sat, 29 May 1993 19:30:46 GMT
From: Roger Lustig <[e-mail]>
Subject: Tom Wolfe's THE RIGHT STUFF - Truth or Fiction?
Newsgroups: sci.space,sci.space.shuttle,rec.arts.books

In article <[e-mail]> [e-mail] (Richard Ottolini) writes:
>This book/movie evokes memories of the "Golden Age" of science and
>exploration.  It hasn't really ended, but since the late 1960's much
>of the public has been skeptical and ignorant about science.

Most of the public has *always* been ignorant about science.

As for when the enthusiasm wore off, try 1918.

>The last time I felt this public enthusiasm was when I lived in
>China some years ago.  They still believe in science and technology there.

They did in the SU, too.  Hmmm...

Roger

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

Date: 28 May 93 18:18:08 GMT
From: the Smooge <[e-mail]>
Subject: Voyager Discovers the First Direct Evidence of the Heliopause
Newsgroups: sci.space,sci.astro,alt.sci.planetary

What is the mechanism for the generation of the 2-3 kilohertz
frequency. It isnt blackbody radiation, nor would it seem to be
bremstralung. Any help would be appreciated, as I am quite interested
in the subject.

--
Stephen John Smoogen                    | PseudoAstrophysicist
[e-mail]                     | Computer Scientist
-- The clouds are always darkest before the Storm. --   | System Administrator

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

Date: 30 May 1993 01:57:09 GMT
From: "David M. Palmer" <[e-mail]>
Subject: Voyager Discovers the First Direct Evidence of the Heliopause
Newsgroups: sci.space,sci.astro,alt.sci.planetary

[e-mail] (Ron Baalke) writes:

>     In May and June 1992, the sun experienced a period of intense
              ^^^^
>solar activity which emitted a cloud of rapidly moving charged
>particles.  When this cloud of plasma arrived at the heliopause,
>the particles interacted violently with the interstellar plasma
>and produced the radio emissions, according to Gurnett.

A brief correction, the solar activity was in May and June 1991.

Also, the 21 May 1993 issue of Science has a paper on a different
measurement which comes to about the same conclusion re the distance to
the heliosphere.  This measurement uses absorption lines in the spectra
of nearby stars to estimate the Sun's speed relative to the Local
Interstellar Cloud (LIC), and measurements of the speeds and densities
of comonents of the LIC which have passed through the heliopause and
into the solar system to be measured by various space probes.

The LIC is a cloud of gas within the local bubble, which in turn is
region of low density gas density in space, thought to have been swept
out by recent nearby supernovae.  At our current speed, which turns out
to be 26 km/s, the Sun has been in the LIC for 200,000 years, and will
be for 100,000 more.

Measurements within our solar system shows that the LIC Hydrogen is
slowed down by 6 km/s, while the Helium zips through at its original
speed.  Blah assume blah, this gives a distance to the solar wind
shock of ~100 AU.

--
        David M. Palmer        [e-mail]
                    [e-mail]

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

Date: 29 May 93 14:40:57 EST
From: [e-mail]
Subject: VOYAGER II
Newsgroups: sci.space

Does anyone out there( I mean on the net, not in space!) know the current
status of the VOYAGER II? I thought I had heard something about it recently
and I wanted to do some follow up reading.
                                   -Jason

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

Date: Sat, 29 May 1993 21:27:11 GMT
From: Michael Fennell <[e-mail]>
Subject: What's up with Motorola's Iridium project?
Newsgroups: sci.space

    Several years ago Motorola announced an ambitious program to orbit 77
satellites in low earth orbit to form a global communications network.  Any
person with the proper equipment anywhere on the face of the earth, from Antartica to the Sahara desert to New York City can communicate with the rest
of the world via this satellite network.  There are several major hurdles
the had to overcome to do this:
  1. Financing - this is a multi billion dollar project and Motorola
     can not go it alone financially
  2. Regulations -  they have to get U.S. approval and the approval of
     international communications organizations.  In addition some
     form of approval may be necessary from countries who are afraid
     of loosing control over communications within and with other
     countries.
  3. Launch vehicles - they need an economically feasible means of placing
     these satellites in orbit.
  4. Satellites - they have to design and build satellites
  5. Infrastructure - some nontrivial hardware has to be built or bought
     and assembled for managing the network.

    What is the current status of the program.  Here are some things that I think are true.  Any comments or additions of the list would be welcome.

  1.  The number of satellites has been changed from 77 to 66.  However,
    the project name has not been changed from Iridium (element 77)
    to Dysprosium (element 66).  I guess Dysprosium does not have
    as nice a ring to it!  Questions:  Will coverage be decreased?
    Is the fact that both these numbers are a multiple of 11
significant?

.  I remember reading that Motorola got some U.S. and international
approval last year, but I don't know what or how much.

3.  Motorola says it has financing, but I don't remember the names
of the investors.  Any word on the financing?

4.  Lockheed is involved in the launching and design of the satellites.
What launch vehicles are they planning to use?  What is the
status of the satellite development?

5.  Other competitors have announced smaller and less ambitious
projects.  What is their status.

I think this might be an interesting topic for discussion.  As far as
I know, this is the largest single private industrial space venture in ]
history.  What do all of you know about it?

Thanks-
    -mike fennell
n
--
Michael D. Fennell                                         [e-mail]
San Francisco, CA

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

Date: Sat, 29 May 1993 23:21:53 GMT
From: "Phil G. Fraering" <[e-mail]>
Subject: What's up with Motorola's Iridium project?
Newsgroups: sci.space

Mike, a couple days ago Wales Larrison posted on sci.space
his most recent Commercial Space Report, with some information
on Motorola's Iridium (oops, Dysopropium?) satellite network.
He also wrote about some "competing" ventures, like Orbcomm.

I'm not sure that Iridium is the largest commercial space venture
so far, but launch costs aren't as much of a problem here as
satellite cost, _and_ a large venture isn't necessarily the one
most likely to succeed (see Mr. Larrison's comments on Orbcomm).

(That's all I remember that I really had problems with in your
original post, but please correct me if I'm wrong.)

If you really need it, and it's really expired on your system,
(and remember, I have friends using netcom, so I can check ;-)
I'll mail the last report to you.

--

+-----------------------+---------------------------------------+
|Phil Fraering          | "...drag them, kicking and screaming, |
|[e-mail] | into the Century of the Fruitbat."    |
+-----------------------+-Terry Pratchett, _Reaper Man_---------+

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Date: 29 May 1993 14:43:43 -0400
From: Pat <[e-mail]>
Subject: Why a far side Science station.
Newsgroups: sci.space

Simple solution..  Just put the science station on the near side
and  spin the moon up with gyros, so that the stastion is on the
far side:-)

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End of Space Digest Volume 16 : Issue 648
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