Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V16_2/V16NO238.ZIP/V16NO238

Internet Message Format | 1993-07-13 | 32KB

Date: Mon,  1 Mar 93 05:10:08
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #238
To: Space Digest Readers
Precedence: bulk


Space Digest                Mon,  1 Mar 93       Volume 16 : Issue 238

Today's Topics:
                  Alternative Space Station designs
                   Apollo Missions (Recollections)
                       Aurora (rumors) (2 msgs)
                         Battery help needed!
                   Book Computers/AI in Shuttle-SSF
                            Fallen Angels
                Freedom refueling (Mir-Progress, long)
               Galileo Antenna: Net Brainstorm Session?
                   Human Distance Record:Apollo 13
                       Nobody cares about Fred?
                       payload return from Fred
                      SOLAR gravity assist? Yup.
                      Space IR telescope schemes
       SSF Resupply (Was Re: Nobody cares about Fred?) (2 msgs)
                          The Future of Fred
                           UN Space Agency?

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Date: Fri, 26 Feb 1993 00:51:12 GMT
From: "Phil G. Fraering" <[e-mail]>
Subject: Alternative Space Station designs
Newsgroups: sci.space

[e-mail] (Edward Dansavage Wright) writes:


>Info request to the net....

>I am interested in space station designs not based on the
>"power tower" concept as was/is Freedom.  I am interested in
>alternative designs such as inflatable structures, geodesic
>dome configurations etc.  Could someone please provide a starting
>place to look for this information?  Is there a particular NASA
>installation I should contact?

Freedom isn't based on the "power tower" but the "dual keel"
config instead (although one of the keels is missing or
something).

A geodesic configuration probably wouldn't be needed, but do a
search of the periodicals index under "Oliver Harwood" to find out about
the ideas of an engineer who was thinking of using something slightly
similar... (i.e. a geodesic framework, not a dome).


>As always,
>Ed Wright
>University of Wisconsin at Madison

Please be careful. There's another Edward Wright who posts regularly
to this group.

Hey, Gary, it's time to get scared! There's two of him!

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

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

Date: Fri, 26 Feb 1993 02:40:31 GMT
From: Dave Michelson <[e-mail]>
Subject: Apollo Missions (Recollections)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] ((Michael Gerhard  aka Elmo P. Suggins)) writes:
>
>Since I missed almost all of the 1969 TV coverage of Apollo 11, it was a
>real treat when in July of 1989, celebrating the 20th anniversary of the
>landing, that A&E cable channel rebroadcast the entire CBS(?) coverage of
>the mission...

Actually, A&E rebroadcast the *NBC* news coverage.  (NBC is one of the owners
of A&E :-)

>Anyone else with good memories?

As Dan Rather said on the 1989 CBS show "The Moon Above, The Earth Below",

   "The America of 20 years ago... they did things differently."

Interesting note:  At one point, there were plans to launch at least three
(possibly four) space stations during the late 1960's - one or two MOL's
and two or three AAP workshops.  At least they got one up by 1973!


---
Dave Michelson                             University of British Columbia
[e-mail]                                  Antenna Laboratory

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

Date: 26 Feb 93 04:42:33 GMT
From: Dean Adams <[e-mail]>
Subject: Aurora (rumors)
Newsgroups: sci.space

[e-mail] writes:
 >The plane must have been flying at an altitude of at least 10 kilometres,
 >because it was not picked up on radar.

Since when does radar stop at FL 300?  ATC radar should cover that
territory quite well.  Also, Aurora could very likely incorporate
stealth characteristics.  That is still no reason to go blaming
every strange "explosion" on Aurora.

 >Similar explosions have been reported in the US over the past year,
 >notably in the Los Angeles area, where seismologists detected acoustic
 >shock waves.

I have never heard L.A.'s skyquakes called "explosions".

 >(end of article)
 >This Aurora seems really dangerous for people (near-collisions),

Are you kidding??  There has been ONE report of a near miss.
That makes it "really dangerous"?  Come on!  Get real...

 >buildings and environment (shock waves).

WHERE has Aurora been "really dangerous" to buildings or the environment?

 >Also, it has a strange habit of shouting "Hi folks, I'm coming to
 >spy on you !".

NO, it has an occasional habit of shouting "Hi, i'm back from spying".
At *OPERATIONAL* speeds and altitudes, there would not likely be any
noise detectable from the ground...

 >The best would be to stick it on the ground.

And exactly why do you say that?   Too much competition with "UFOs"?  :->

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

Date: 25 Feb 1993 23:41:56 GMT
From: steve hix <[e-mail]>
Subject: Aurora (rumors)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>
>This Aurora seems really dangerous for people (near-collisions),

Fly around long enough in civil airspace without filing flight plans...

>buildings and environment (shock waves). Also, it has a strange
>habit of shouting "Hi folks, I'm coming to spy on you !".

More on the order of "Bye, I have just left the neighborhood."
(By the time you hear the sound, the aircraft is gone.)

>The best would be to stick it on the ground.

I would certainly hope not.  It would be nice to de-classify
it sometime, though.





--
-------------------------------------------------------
| Some things are too important not to give away      |
| to everybody else and have none left for yourself.  |
|------------------------ Dieter the car salesman-----|

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

Date: 26 Feb 93 05:00:45 GMT
From: "kevin.w.mckiou" <[e-mail]>
Subject: Battery help needed!
Newsgroups: sci.space,sci.electronics,sci.aeronautics,sci.chem,sci.engr

In article <[e-mail]> [e-mail] (Benjamin John McCall) writes:
>Does anyone have any information on alternative battery technologies, or
>even suggestions about who I might get in touch with (by phone or by email)?
>

You might look into Ni-Cads.  100 lbs of Sanyo high-capacity cells
KR-2800CE could deliver ~163 amp-hours at 12 volts.  That's just
19% short of your goal.  I would try contacting Sanyo directly to
get some idea of what else might be available.

Good Luck!

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

Date: 25 Feb 1993 22:17:12 -0500
From: Pat <[e-mail]>
Subject: Book Computers/AI in Shuttle-SSF
Newsgroups: sci.space

In article <[e-mail]| [e-mail] (Henry Spencer) writes:
|In article <[e-mail]> [e-mail] (Gary Coffman) writes:
|
|>Might work inside the
|>Shuttle until someone drifted in front of the sensor...
|
|Actually, I believe the Shuttle program is already using infrared
|technology for the communications headsets worn inside.


I thought the SUits already had a qualified IR system.
Is the IR system only for the crew area?

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

Date: 26 Feb 93 02:31:46 GMT
From: James Thomas Green <[e-mail]>
Subject: Fallen Angels
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (FRANK NEY) writes:
>
>In the SF book 'Fallen Angels' by Larry Niven & others, a launch
>vehicle named PHOENIX was described.  In the afterward, it was claimed
>that such a launch vehicle (SSTO/VTOL) could be build for $50M-200M.
>
>Anyone have information on the design of this critter?
>

See all the posts about DCX/Y/1/etc and SSTO . . .

POHENIX = SSTO


/~~~(-: James T. Green :-)~~~~(-: [e-mail] :-)~~~\
|I didn't do it! Nobody saw me do it! You can't prove anything!    |
|                                   <Bart Simpson>         |

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

Date: Thu, 25 Feb 1993 19:59:46 GMT
From: Dennis Newkirk <[e-mail]>
Subject: Freedom refueling (Mir-Progress, long)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Josh Hopkins) writes:
>Allen, could you (or perhaps Dennis Newkirk) post a description of just how the
>Russians refuel Mir?  It's not imediately obvious to me that they do an EVA to
>refuel.  I'm not saying they don't, I'd just like someone to actually explain
>what they do before we all take it for granted.

See below.

>>>|> Maybe we don't need tankage. Maybe we use fuel from the OMS.

On some STS flights they dump OMS propellant to get the center of mass
desired for reentry (usually they burn opposing thrusters) so there is
left over propellant sometimes. The Russian Progress M system has a way
around this waste, read below.


Salyut/Mir Space Station Refuelling and Resupply
Copyright (C) 1993, by Dennis Newkirk

For those who don't know, Salyut 6-7 and Mir use a pressure fed storable
propellant propulsion module at the rear of the station designated OUD.
The system includes 2 main engines (1 on Mir), 4 blocks of attitude
control thrusters and 6 propellant tanks positioned around the rear
docking port. The main engines are rarely used since spacecraft are
usually docked at the port (and not really trusted after many years of
disuse). When this is so, the docked spacecraft are used to boost the
stations orbit whenever propellant supplies allow.

Progress Description

The Progress was a highly modified version of the Soyuz, used to auto-
matically deliver cargo to the space stations. The Soyuz design was altered
by replacing the capsule with a tankage section.  The Progress spacecraft
usually weighed about 7,020 kg. at launch depending on the amount of cargo.
Payload capacity was 2300 kg. of which about 1000 kg. was maximum weight of
propellants, and 1300 kg. maximum orbital module cargo.  It was 7.94 meters
long and 2.7 meters diameter at the base.  Internal volume of the cargo module
was 6.6 cubic meters.  The docking collar of the Progress includes propellant
line connectors in addition to the standard electrical and communication
connections. The Progress docked only at the aft port of Salyut 6 and 7
stations because it was the only port with propellant line connections. Mir
forward and aft (and Kvant) ports are equipped with the connections.  The
Progress service module used a modified version of the OUD pressure feed
engine system. The Progress was also used to test the new engine system before
the beginning the Soyuz T flights, which used the same system.

The pressurized instrument section of the service module was lengthened and
equipment for automatic docking was apparently installed in this additional
space.  The Progress carried twice as much instrumentation for rendezvous
and docking as the Soyuz.  In the cargo section, pressure was maintained at
760 mm. but temperature varied from 3 to 30 C during flight.  Special
equipment carrying racks were installed depending on the cargo to be carried.
The hatch, with the docking probe, could be opened automatically or manually.
Another feature of the docking hatch and probe was the ability to remove the
entire hatch from its mounting, to facilitate movement of cargo.  The probe
is stored in the space station and installed or stowed in the Progress before
undocking.

The Progress could carry enough cargo to supply a Salyut with two or three
cosmonauts for three to six weeks.  One figure quoted by the soviets was
30 kg. supplies per-person per-day.  A typical cargo consisted of 200 kg.
of water, 600 kg. of propellant, 250 kg. of food, 450 kg. of air,
experiments, mail, replacement parts, materials samples, fresh food, video
taped movies, concerts and cartoons, clothes, books and music and nature
sound cassettes.

Propellant was transferred from the Progress to the station by closing off
the stations tanks and using a pump to lower the pressure of the tanks
from an operational pressure of 220 Atmospheres, to about 3 Atmospheres
by extracting nitrogen from the tanks flexible bellows. This took several
hours because the pumping consumed a quarter of the Salyut station's
electrical power (one kilowatt) and the Salyut's batteries had to be
recharged periodically during the process.  The Progress tanks were
pressurized to 8 Atmospheres using its own nitrogen supply.  When the
valves were opened, most of the propellant flowed to the stations tanks
which were then closed off refilled.  The same process was used for both
fuel and oxidizer tanks.  The lines in the docking collar were then purged
with nitrogen after refueling, to prevent the volatile fuel and oxidizer
residue from spilling out onto the station after undocking. It was not
uncommon for fuel and oxidizer transfers to be done days apart, and never at
the same time probably due to power constraints and safety concerns.
All refuelling operations can be done remotely from mission control, and
usually cosmonauts only observe.

The cosmonauts usually observe the docking of the Progress from 10 km.
distance and could boost the station away from a malfunctioning ship.  The
cosmonauts could orient the station manually during the docking or let the
stations automatic systems point the station.

The Progress' were unloaded and refilled with waste, used equipment and air
regenerators.  Special tools for unfastening the equipment in Progress were
carried on Salyut stations including a recoilless hammer, a lock-on
screwdriver, pliers, and a power screwdriver.  Many items like air
regeneration tanks, clothes and human wastes were disposed of using Progress
ships that burn up on re-entry.  When a Progress was not available, the
cosmonauts put the small trash in bags and put it out through the scientific
airlocks.  These bags quickly fell into the atmosphere and reentered due to
atmospheric drag after about a month. This is used rarely on Mir.

Progress M Description

Revised Progress design using a Soyuz TM service module, Kurs (enabling
docking at the forward Mir port which does not have Igla), and solar panels.
The propellant section was connected to the propulsion section so propellant
can be shared and unused orbital maneuvering propellant transfered to the
station.  The cargo compartment (orbital module) was slightly lengthened
adding 1 cubic meter to the volume, and payload capacity was increased by
200 kg. (2700 kg. total).  Capable of indepandent flight for up to 30 days.
Docked lifetime is 108 days.

The orbital module also can be equipped with a NPO Energia return capsule
capable of carrying 100-150 kg..  The capusle is carried in the orbital
module and is used to replace the docking probe after filling the Progress
with trash, and the old probe.  The capsule is 60 cm. in diameter.
After retrofire the capsule seperates and pressure sensors trigger parachutes
after reentry.

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

Date: 26 Feb 93 03:14:28 GMT
From: Keith Johnston <[e-mail]>
Subject: Galileo Antenna: Net Brainstorm Session?
Newsgroups: sci.space

Dear netters:

This is the first time I have posted to this group, but I
have always found the net to be full of great ideas from
people around the world.

I was wondering if those who are more knowledgable than I might
enlighten the rest of the net with the problem of Galileo's
antenna to see if someone out there might come up with a way
of getting it unstuck!

This may have already been done, but if it hasn't, why not?

                    Keith Johnston

--
JOHNSTON,KEITH BARKER
Georgia Institute of Technology, Atlanta Georgia, 30332
uucp:      ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!gt1057a
Internet: [e-mail]

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

Date: 25 Feb 93 14:24:36 GMT
From: Jonathan McDowell <[e-mail]>
Subject: Human Distance Record:Apollo 13
Newsgroups: sci.space

From article <[e-mail]>, by [e-mail] (Dillon Pyron):
>
> Okay, now for a toughie (I don't know the answer, I'm really looking for it).
>
> Who was the loneliest man in the Universe?  In other words, which of the Apollo
> "third men" got furthest from his teammates, and was, hence furtherest from any
> living human?  That we know of  :-)


Wow, that's a toughie!

Ken ("T.K.") Mattingly holds the record for the most *time* spent
alone on the lunar farside, in the longest US solo spaceflight
aboard CSM-113 Casper (the Apollo 16 CSM), 81 h 29 min, of
which some fraction (anybody know how much) was spent out of
contact with all other humans, with the body of the Moon between
him and everyone else. In my book, this makes more loneliness
that simple distance.

But *distance* is trickier. I tried looking at the post-undocking lunar
orbits of the CSMs, and the one with the highest apoapsis was CSM-114
America (Apollo 17 CSM), with 130 km altitude. But they're all pretty
similar, the lowest being 118 km, and the errors introduced by time
variation of the orbit induced by mascons and by uncertainty in the
distance to the LM due to the non spherical shape of the Moon are
probably larger than the differences bweteen the orbits for different
missions. It's even possible that the dominant uncertainty is
tracking errors - errors in our knowledge of the position of the
CSM for the early missions not carrying a radar altimeter - and
so the answer may not even be derivable from archival tracking records
if they still exist.

- Jonathan McDowell

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

Date: Fri, 26 Feb 1993 00:44:58 GMT
From: tomas o munoz 283-4072 <[e-mail]>
Subject: Nobody cares about Fred?
Newsgroups: sci.space

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

|> The biggest thing which needs to be brought down only weighs a few thousand
|> pounds. We could build a logistics module with a kick motor and heat
|> shield and return the few things we need that way.

I don't know what you mean by "need to be brought down" or
"few thousand pounds".  From SSF resupply/return studies,
approximately 90 - 95 percent of everything that is planned
for delivery to the SSF will need to be returned; This number
does not include the crew or the orbiter, just logistics items
and logistics carriers.  That's 90-95% of delivered mass in
the ~150k-200k lbm range.  Maybe that is a few thousand pounds.
If you start saying lets get rid of trash [food garbage, etc...]
then you could drop down to approximately 85%.  You will then
need to develop a trash disposal system.

You can't just send stuff to orbit and leave it there.  That's
MSFC's booster mentality.


--
Tom Munoz
==================================================================
Thought for the day: "One million microfiche = one fish"
 ___________      ___     ____    ____
/_________ /|   /___/ \  /__ /\  /___/|
|___   ___|/  /  _  \ /| |   \ \/   | |
    |  | |   |  | |  | | |    \/    | |
    |  | |   |  | |  | | |  |\  /|  | |
    |  | |   |  |_|  |/  |  | \/ |  | |
    |__|/     \_____/    |__|/   |__|/ [e-mail]
==================================================================

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

Date: Fri, 26 Feb 1993 04:30:36 GMT
From: Henry Spencer <[e-mail]>
Subject: payload return from Fred
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (tomas o munoz 283-4072) writes:
>|> The biggest thing which needs to be brought down only weighs a few thousand
>|> pounds. We could build a logistics module with a kick motor and heat
>|> shield and return the few things we need that way.
>
>I don't know what you mean by "need to be brought down" or
>"few thousand pounds".  From SSF resupply/return studies,
>approximately 90 - 95 percent of everything that is planned
>for delivery to the SSF will need to be returned...

True, but that's not what he said.  What he said was that the (single!)
biggest thing that needs to come down in *one* *piece* only weighs a few
thousand pounds.  You don't need to bring trash down in twenty-ton lots.
We can return few-thousand-pound objects using off-the-shelf reentry
technology.  For trash, omit the heatshield.

>You can't just send stuff to orbit and leave it there...

Why not?  Most of it will be more useful up there than down here.  And
a heavier station is *better*, because it reduces the frequency with
which reboost is needed; even trash is more useful as station ballast
than as return cargo.
--
C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology
effect since OS/360.                    |  [e-mail]  utzoo!henry

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

Date: Fri, 26 Feb 1993 04:32:07 GMT
From: Henry Spencer <[e-mail]>
Subject: SOLAR gravity assist? Yup.
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Paul Dietz) writes:
>Bill Higgins asks about a "solar gravity assist".
>
>This is *not* the same as the more well-known Jupiter gravity assist.

Paul, go back and read Bill's posting much more carefully.  He really
is talking about a Jupiter-style gravity assist, not an Oberth gravity-
well maneuver.  And no, he has not lost his marbles.  Read his posting.
--
C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology
effect since OS/360.                    |  [e-mail]  utzoo!henry

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

Date: 25 Feb 93 12:57:21 GMT
From: [e-mail]
Subject: Space IR telescope schemes
Newsgroups: sci.space,sci.astro

In article <[e-mail]>, [e-mail] writes:
> I wrote:
>> |> To continue to the next logical step, we need to build and launch SIRTF.
>> |> The IRTF (Infra-Red Telescope Facility) on Mauna Kea will always be
>> |> stymied by that same atmosphere.  Using what we've learned from HST we
>> |> can build a high quality IR telescope for space observations.
>
> and Dave Rickel replied:
>> There was a proposal in SPACEFLIGHT a couple months back to build a large
>> passively cooled IR telescope.  I seem to remember that they proposed sticking
>> it in the L-2 spot (presumably the sun-earth L-2 spot).  Is this SIRTF, or
>> something else?
>
> Not the SIRTF I know of, but the planning for SIRTF is so nebulous right
> now that it well may be a suggested modification.
>

The proposed instrument is not a redesign of SIRTF but a new proposal,
initially from Harley Thronson and Tim Hawarden, called EDISON. It would have a
passivly cooled mirror and support structure with actuvely cooled detectors,
probably using closed-cycle cryogenic fridges. This allows a large refelctor,
eg. similar in size to the HST mirror (perhaps a use for the spare???), which
would cool down to about 50K over a long period. In contrast SIRTF and ISO use
cooled primary mirrors, at 4K, but then have to have very small mirrors (0,5 m
or under) and have limited lifespan.

I may be able to forward an article by Amanda Baker on EDISON written for the
UKSEDS magazine if anyone is interested.

Dave

--
================================================================================
Dave Clements, Oxford University Astrophysics Department
================================================================================
clements @ uk.ac.ox.vax            |  Umberto Eco is the *real* Comte de
dlc      @ uk.ac.ox.astro        |           Saint Germain...
================================================================================

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

Date: Thu, 25 Feb 1993 23:51:01 GMT
From: tomas o munoz 283-4072 <[e-mail]>
Subject: SSF Resupply (Was Re: Nobody cares about Fred?)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Frank Crary) writes:

|> >...You would still have
|> >to completely redesign the system for on orbit refueling.
|>
|> Perhaps that should have been done from the start.

Actually, this was done from the start with the original O2/H2
propulsion system which would use water from the orbiter fuel
cells.  It was scrapped for the cheaper [upfront $] present design.

|> Last time I checked, 200 not 270 nm was the operational altitude of
|> Freedom. Also, as I recall, Mir reboosts every month or so as a
|> general rule. Freedom would require replacement of its station keeping
|> motors after 180 days of normal operations. However, there are

Last time I delivered altitudes to the SSF program they ranged
between ~180 nmi and ~270+ nmi depending on solar cycle.  There
is not defined operational altitudes right now and they certainly
will not be constant altitudes.  However, there is a regime
which defines where the SSF will fly.

|> things that can be done, in extreme emergency, to increase this:
|> Using all available fuel to boot to a high orbit, and putting
|> the solar arrays into a minimum drag cross section pointing would
|> extend the station's life to a year or two without resupply. However,
|> that would have very serious consequences: A roughly fifty percent
|> reduction in power (is that even enough to keep life support and
|> housekeeping running?) and the station would be inaccessable to
|> the Shuttle until it's orbit had decayed (I'm not a ACRV could
|> make an emergency crew return from such a higher orbit, either.)

This reboost will not send SSF out of Shuttle's altitude capability.

--
Tom Munoz
==================================================================
Thought for the day: "One million microfiche = one fish"
 ___________      ___     ____    ____
/_________ /|   /___/ \  /__ /\  /___/|
|___   ___|/  /  _  \ /| |   \ \/   | |
    |  | |   |  | |  | | |    \/    | |
    |  | |   |  | |  | | |  |\  /|  | |
    |  | |   |  |_|  |/  |  | \/ |  | |
    |__|/     \_____/    |__|/   |__|/ [e-mail]
==================================================================

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

Date: Fri, 26 Feb 1993 00:11:32 GMT
From: tomas o munoz 283-4072 <[e-mail]>
Subject: SSF Resupply (Was Re: Nobody cares about Fred?)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Frank Crary) writes:

|> A Titan IV should be able to deliver an extra ACRV. I also don't
|> see why you couldn't put a few people in that extra ACRV, and
|> thereby both deliver and retrieve humans.

I'd like to hea the astronaut office express their views on
putting crew on top of a Titan IV in a vehicle with no
manual control capability.

|> >How do you perform the actual payload transfer from the expendable
|> >to the SSF if the SSF is unmanned? - You really need IVA for this
|> >operation.
|>
|> Which sort of unmanned: After MTC, you just need to get people to
|> the station, and there are only a few launches (low risk) before
|> MTC.

No, after MTC you still 11 assembly flights and 8 utilization
flights.  I don't quite understand your definition of low risk.

|> >This is true at almost any place along SSF assembly.  In the PMC
|> >phase, you have the ability to fully feather the PV arrays and have
|> >orbital lifetime ranging up to ~1.5 years.
|>
|> At the price of almost complete (complete? What exactly do you
|> mean by "fully" feather?) loss of power.

Yes, at the price of very little power generation.  However,
you can go to a minimum power configuration and remove the
crew to achieve this.  Fully feathered means the edge of the
solar arrays to the "wind" in an LVLH orientation.  Fully
feathered does not mean zero power, because at times in the
orbit [orbital noon], fully feathered arrays point directly
to the sun and generating full power capability.

--
Tom Munoz
==================================================================
Thought for the day: "One million microfiche = one fish"
 ___________      ___     ____    ____
/_________ /|   /___/ \  /__ /\  /___/|
|___   ___|/  /  _  \ /| |   \ \/   | |
    |  | |   |  | |  | | |    \/    | |
    |  | |   |  | |  | | |  |\  /|  | |
    |  | |   |  |_|  |/  |  | \/ |  | |
    |__|/     \_____/    |__|/   |__|/ [e-mail]
==================================================================

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

Date: 26 Feb 93 03:00:39 GMT
From: Michael Pereckas <[e-mail]>
Subject: The Future of Fred
Newsgroups: sci.space

[e-mail] writes:

>PS just to make sure you know, the batteries are in building 4487 room
>C101. This is the Skylab battery room and is still in use. Too many on

>here forget things like the battle for the power system that pitted
>the DC power system against a 20 khz AC system. This battle was won and
>is one of the unknown things done to build a good station.

This is the kind of thing I like to hear about.  Can you fill us in?
I remember hearing something about 20 kHz power a few years ago, but
nothing since.




--
Michael Pereckas    [e-mail]
"The more I stab myself in the foot, the less I want to kick my head off."

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

Date: Fri, 26 Feb 1993 00:47:01 GMT
From: "Phil G. Fraering" <[e-mail]>
Subject: UN Space Agency?
Newsgroups: sci.space

phoenix.Princeton.EDU!carlosn (Carlos G. Niederstrasser) writes:

>In article <[e-mail]> [e-mail] writes:
>> Is there a UN Space Agency and if there is can someone post info here and
>> forward the info to me here: [e-mail]

>They have the Committee for the Peaceful Uses of Outer Space (COPOUS)

>Chair is a Mr. Jasentuliyana (Sp?)

If this is COPOUS as in COPOUS treaty, then it's probably a bunch of
third-world jerks (and assorted liberals from everywhere else) whose
countries can't keep up a satellite for more than 2 weeks whining
about how space is used by the West to oppress the South... (and
they ain't talking about Dixie, if you know what I mean).

>---
>---------------------------------------------------------------------
>| Carlos G. Niederstrasser        |   It is difficult to say what   |
>| Princeton Planetary Society     | is impossible; for the dream of |
>|                                 | yesterday, is the hope of today |
>|                                 |   and the reality of tomorrow   |
>| [e-mail]   |---------------------------------|
>| [e-mail]     |    Ad Astra per Ardua Nostra    |
>---------------------------------------------------------------------
                                   Perhaps: Ad Astra pre la Cosa Nostra?


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

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End of Space Digest Volume 16 : Issue 238
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