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Subject: SPACE Digest V9 #362

SPACE Digest                                      Volume 9 : Issue 362

Today's Topics:
             space news from Feb 20 AW&ST
     Re:  Success with cold fusion reported, (Really Power Grids)
             Re: DSN mission launch dates
           Re: space news from Feb 13 AW&ST
               Re: Questions and Henry
          Re: Building a fusion-based rocket
             Re: Power vs Energy
----------------------------------------------------------------------

Date: 12 Apr 89 03:01:51 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: space news from Feb 20 AW&ST

[A correction:  despite the comments in AW&ST, folks from both Fermilab
and CERN have pointed out that Fermilab currently holds the record as
the world's biggest antimatter source.  Not that that's such a massive
distinction, mind you:  if all the antiprotons produced to date were
combined with positrons to make antihydrogen, there would be roughly
enough to fill an anti-ping-pong ball at one atmosphere.  (My thanks to
a friend at CERN for this information.)]

India asks France for technological assistance in launch-vehicle
development, specifically nozzle design, cryogenic propulsion, and
clustering of liquid engines.  [Fat chance.]

First Delta 2 launch successful Feb 14.

NASA is upset about a coming personnel crisis:  70% of its senior
managers are eligible for retirement within two years, and many of
them are expected to leave.  Fletcher says the situation is "desperate".
(AW&ST's editorial this week inquires why this problem took Fletcher
et al by surprise, given that it's been obvious since the hiring freezes
in the 1970s that there would be few middle-aged managers to replace the
old ones.)  NASA is considering ideas ranging up to turning several of
the NASA centers into contractor-run facilities.  The problem is that
NASA cannot afford to pay enough to keep its managers or hire people
with equivalent experience.  There has also been an unusually high
number of resignations among newly-hired managers of late.  [To be
blunt, if NASA forgets silly ideas like privatizing some of the centers
and just tries to muddle through, this could be the best thing that's
happened to it in a long time.  NASA's supervisor:worker ratio today is
much too high, twice what it was during Apollo.  Putting some of the
relatively young and inexperienced people in positions of responsibility
might be just what's needed to get things moving again.]

Florida governor asks state legislature to set up a Spaceport Authority
to establish commercial launch facilities at the Cape (preferably using
some existing mothballed pads) and a sounding-rocket range on property
owned by Eglin AFB.  The Bush Administration supports the idea in general.
Many people doubt that there is enough long-term demand to justify such
a project, though.

Arianespace signs contracts for the production batch of 50 Ariane 4s.
The bulk buy is expected to cut costs by about 20%.

Article on preparations for the first Titan 4 launch, which will carry
an upgraded-version Defense Support Program early-warning satellite.
The infrared telescope is expected to return useful intelligence data
as well; the latest upgraded version is known to be capable of
tracking aircraft if they are using afterburners.  Among other minor
improvements, this DSP version has computer and software improvements to
manage its own systems and station-keeping if cut off from ground command.
The next one, to go up on the shuttle next year, will add a laser
communications system which will link it to other DSP satellites,
allowing "sideways" data relay to circumvent jamming.  There is a faction
which wants to continue upgrading the DSP series rather than replacing
it with the SDI-developed BSTS system.  An interesting set of photos
comparing successive generations of DSP birds, with successively more
elaborate sensors and bigger solar arrays.

Navy begins construction of four Lightsats for launch this fall, pulling
ahead of the USAF (which fought the concept for a while).  The first
three, carrying various experimental packages, will go up together on
a Scout (probably).  The fourth, carrying an experimental system to
locate sources of radio interference, is almost finished but does not
have a definite launcher yet:  Scout and Pegasus are possibilities.
[Smells like they want to use Pegasus but don't want to say so until
it flies successfully.]  These are basically R&D missions, although
they may have some operational utility if they work well.  The official
position right now is that these are "niche" spacecraft that cannot
replace the big expensive ones.  [That may change if they work well.]

NRC report says SDI beam-weapon work implicitly assumes availability
of advanced space power sources, on which little work is being done.
One significant issue, for example, is whether exhaust and vibration
from chemical systems make them unacceptable; only analytical studies
have been done on this, with inconclusive results, and the space
experiments that would settle the question are several years off and
have low priority.

USAF building special single-point suspension facility to study the
control dynamics of large lightweight space structures.

Pratt&Whitney offers various upgrades for the RL10 engine to Centaur
customers; business is booming.  Some of the upgrades are derived
from work done on the late, lamented Shuttle-Centaur program.

Study commissioned by Comsat Corp. shows satellites holding their own
against fiber-optic cables for the near future.
--
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry [e-mail]

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

Date:     Mon, 10 Apr 89 8:17:08 CST
From: Will Martin -- AMXAL-RI <[e-mail]>
To: sgi!shinobu!shinobu.sgi.com![e-mail]
Cc: [e-mail]
Subject:  Re:  Success with cold fusion reported, (Really Power Grids)

>This implies something that deserves explicit mention: there is nothing
>I know of that makes a "grid" incompatible with decentralizing energy
>production.  In at least some places, individuals with windmills sell
>their surplus power back to a utility.  If each household made enough
>power on the average, couldn't we still use the "grid" just to balance the
>load?  What if utilities stopped producing and became brokers?

I had just recently read an article on home power generation in a back
issue of "Blair & Ketchum's Country Journal" magazine -- July 1985, p. 54.
The article is on hydro power, but the issues regarding tying into the
power grid are applicable to any source.

"A generator must turn at a constant speed to produce electricity at
a constant voltage. There are two basic ways to keep that speed
constant. One is to make sure that the generator is always running under
the same load -- a full load. Since a home's electric needs change as
heating units and appliances go on and off, a switching mechanism can be
built into the power plant. The house gets whatever it needs, and the
remainder can be sold to the power company."

"There are some complications with this... One is that the equipment to
connect with the utility system isn't cheap. [A 50 kW unit's tie-in
circuitry] cost about $8000, although power sales will eventually recover
that cost. Another difficulty, an ironic one for someone with a generator
in the yard, is that when the commercial power is off you can't be running
your generator and so you won't have power either...

That's because such connected generators ... need commercial power to keep
them in step with the rest of the system, unless they have costly additional
control mechanisms. Besides that, if the power is off somewhere else in the
utility grid, the power company can't let you keep gnenerating, even if you
had those controls. ... They have crews out fixing the lines. The power is
supposed to be off in those lines. But if you're generating, and you're
connected, then there's power going into those lines that are supposed to be
dead. The lineman could get the last surprise of his life..."

[The other one of the "basic ways" mentioned above is what the subject
of the article does -- he has a quick-acting governor that controls the
flow of water into his turbine and thus varies the electricity produced
directly with the demand.]

Anyway, there can be cost and operational disadvantages from having
individual home generator units tied into the power grid. I must admit
that I like the idea of total independence from commercial power, but I
tend to think that it is still probably more feasible to stay with
central generators and existing distribution grids in built-up areas.
Where the home-fusion plant sounds good, though, is in isolated areas.
It, along with satellite communications, can give rise to more and more
isolated individual smallholdings, independent fiefdoms scattered about
in areas now too inhospitable to support them currently. Now, there are
only a few such, all based on farming, like some of the polygamists'
compounds you hear about at times on "tabloid TV". With independent power
and satellite commo, though, somebody with other skills, like
programming or writing or what-have-you, could live in such a fashion too.

Myself, I always had an idea that it would be interesting to live isolated
in the middle of a mesa big enough to have radial Beveredge antennae (these
are very good but very long short- and medium-wave wire antennae) going
off in about 8 directions... (Probably spelled wrong -- my references
aren't here.) Can't usually get much water in such a situation, though, and,
while solar power might produce enough to live on, a fusion plant would give
enough for air-conditioning and maybe some way to get water...

Regards, Will Martin

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

Date: 10 Apr 89 17:50:00 GMT
From: m.cs.uiuc.edu![e-mail]
Subject: Re: DSN mission launch dates


/* Written  2:40 pm  Apr  6, 1989 by [e-mail] in m.cs.uiuc.edu:sci.space */
/* ---------- "DSN mission launch dates" ---------- */
I just got a list of launch dates for missions supported by the DSN
through 1990.  I don't have a glossary, so if you don't know what
one of these acronyms means, don't ask me.
/* End of text from m.cs.uiuc.edu:sci.space */

BS-3a    ?

COBE        Cosmic Background Explorer
            Determine the spectral anisotropy of the
            cosmic microwave background

DFS    ?    Deutsches something-or-other, I think...

EUTELSAT    EUropean TELecommunications SATellite

FLTSATCOM    FLeeT SATellite COMmunications
            U.S. Navy communciations satellite

GALILEO            Mission to explore Jupiter and its moons

GMS    ?

GOES        Geostationary-Orbit Earth-observation Satellite
            Meteorological mission in Clarke orbit

GRO        Gamma Ray Observatory

HST        Hubble Space Telescope

MAGELLAN        Mission to map the surface of Venus

MUSES-A    ?

ROSAT        ROentgen SATellite
            NASA/West German co-operative mission for
            X-ray astronomy

TDF    ?

TDRS        Tracking and Data Relay Satellite

ULYSSES        (Formerly ISPM--International Solar Polar Mission)
            Investigate the properties of the heliosphere
            (The Sun and its environment).


Kevin Kenny               UUCP: {uunet,pur-ee,convex}!uiucdcs!kenny
Illini Space Development Society   ARPA Internet or CSNet: [e-mail]
P.O. Box 2255, Station A
Champaign, Illinois, 61825       Voice: [phone]

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

Date: 11 Apr 89 02:13:01 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: space news from Feb 13 AW&ST

In article <[e-mail]> [e-mail] (Jonathan Leech) writes:
>>... They really should have launched three of them.]
>
>    Perhaps the effort would better be spent putting more reliable
>hardware on board the spacecraft, and better trained personnel on the
>ground. Of what use would *three* failed Mars probes be? :-)

Of what use would one successful one be?  Note that they didn't lose
P2 to P1's problem.  They probably wouldn't have lost the hypothetical
P3 to P2's problem -- and P2 was pretty close to the key part of the
mission.  One more might have been enough to push the next mistake past
the Phobos encounter.  The way you find out about these things is to try
them.  The major factor in how quickly you learn is how often you try.
--
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry [e-mail]

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

Date: 11 Apr 89 02:32:17 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Questions and Henry

In article <[e-mail]> [e-mail] (Mike Kirby (co-op)) writes:
>1)  Henry, do you have anything positive to say about the U.S. space program?
>    I mean do we do anything right anymore?

Oh, once in a while.  Why, you did something right as recently as 1965. :-)

More seriously, I am quite excited about both Magellan and Galileo.  They
are basically the last big things out of the Apollo-era pipeline, with
very little left in the pipe behind them... but they're nifty all the same.

Much more significantly, the US is possibly the only country that can
really open the skies to mankind.  And despite recent setbacks, it still
has a fair chance of doing it.  The key is to look at private industry,
not government; the US government will never accomplish it, but the US
is nearly unique in being a place where private industry can have a
try at it without having to sell their souls to the government first.

>2)  What is the pegasus?

Pegasus is one of the brightest spots in the picture right now:  a small
air-launched space launcher, being built as a joint project by Orbital
Sciences and Hercules.  Although I'm rooting for them all the way, their
biggest accomplishment will be secure if they launch once and then go
broke:  they've built Pegasus in about two years for about $60M [I may
have that number slightly wrong, but that's the right area].  Even if
they go under after their first launch, they'll have proved that you
don't have to do things the NASA way, spending billions and taking decades.
Private investors can't afford to sink billions of dollars in space
projects and wait decades for possible return... and NASA, from its
entrenched position as The Experts on the matter, naturally assures
them that there is no other way.  Two years and $60M is a very different
story.  If OSC/Hercules get one bird into orbit, others will follow.
--
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry [e-mail]

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

Date: 10 Apr 89 21:04:46 GMT
From: psivax!quad1!ttidca![e-mail]  ( Avatar)
Subject: Re: Building a fusion-based rocket

In article <[e-mail]> [e-mail] (Sandy Michael) writes:
>
>What technology do you see the Earth having by the year 3000?
>Michael Sandy


 Given the actual mission progress since 1945, the current technology, the
extreme attitudes of American management, the inertia-bound political process
that technology must beg it's funds under...plus a few fudge factors...I'd
guess that by the year 3000, if there is no total planetary war to wipe out
the Race..figure maybe we'll have come back up to having SATURN 5's and be
looking at building a real Lunar Colony!

 No :-)'s here! The space effort is being ruined by the big-EGO managers of
NASA, and their "Good-Ole-Boys-Network". Most of these clowns have swell,
college degrees in Mech. Eng. or whatever, but they've never turned a wrench,
cut a part, or designed their way out of an airline barf-bag!! They've all
gone to management "Charm School", and "know" how to motivate! Big !@#$%^ deal!

 I openly challenge anyone with the balls to respond, to explain the huge gap
between NASA management salaries and those of the NASA Engineering staffers.

 They can also explain the nepotism, the wasted paper-chase-studies, the whole
series of bad decisions that lead to the Challenger mess..and then, if it's
not too much trouble, they can explain how, (in light of all this) useful
this 'profession' named management is.

 Scientists and Engineers do not need 5 layers of useless dross between
themselves and the Congress, it only makes the work more expensive and
slower, when is this going to change? By the year 3000? I hope so...
--
-Avatar-> (aka: Erik K. Sorgatz) KB6LUY           +-------------------------+
Citicorp(+)TTI                          *----------> panic trap; type = N+1 *
3100 Ocean Park Blvd.   [phone], ext. 2973 +-------------------------+
Santa Monica, CA  90405 {csun,philabs,randvax,trwrb}!ttidca!ttidcb!sorgatz **

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

Date: 11 Apr 89 02:09:20 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Power vs Energy

In article <[e-mail]> [e-mail] (Jim Meritt) writes:
>Concur that power is an issue in general in space flight, but it should
>not be near the issue that ENERGY is.

It depends on what kind of propulsion we are talking about.  With current
systems, yes, energy is the big problem.  Rocket engines actually handle
rather a lot of power -- an SSME is 5-7 gigawatts, as I recall -- but they
cope by keeping it at arm's length, pushing waste heat back into the fuel
as fast as it (the heat) leaks out.  Trouble is, when you hike the exhaust
velocity (and hence the thrust per kilo of fuel) a few orders of magnitude,
this approach stops working so well.  Will cold fusion get us to that point?
Good question -- wait and see.  Hot fusion probably would; if you look at
artists' conceptions of things like inertial-confinement fusion rockets,
you'll see big radiator fins up forward.
--
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry [e-mail]

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

End of SPACE Digest V9 #362
*******************