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Date: Sun, 2 May 93 05:54:13
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V16 #511
To: Space Digest Readers
Precedence: bulk
Space Digest Sun, 2 May 93 Volume 16 : Issue 511
Today's Topics:
Gamma Ray Bursters. WHere are they.
Gamma Ray Bursters How energetic could they be?
HST Servicing Mission Scheduled for 11 Days (3 msgs)
Long term Human Missions
Long Term Space Voyanges and Effect NEwsgroup?
Mars Observer Update - 04/30/93
moon image in weather sat image
Philosophy Quest. How Boldly?
Revival of San Marco? (was Re: Commercial Space News #22)
Satellite around Pluto Mission?
Single Launch Space Station
Two-Line Orbital Element Set: Space Shuttle
Vandalizing the sky.
What planets are habitable
Welcome to the Space Digest!! Please send your messages to
"space@isu.isunet.edu", and (un)subscription requests of the form
"Subscribe Space <your name>" to one of these addresses: listserv@uga
(BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle
(THENET), or space-REQUEST@isu.isunet.edu (Internet).
----------------------------------------------------------------------
Date: Fri, 30 Apr 93 14:43:41 GMT
From: Bob Combs <bobc@sed.stel.com>
Subject: Gamma Ray Bursters. WHere are they.
Newsgroups: sci.space
Picture our universe floating like a log
in a river. As the log floats down the
river, it occasionally strikes rocks, the
bank, the bottom, other logs. When this collission
occurs, kinetic energy is translated into heat, the
log degrades, gets scraped up, and other energy
translaions occur. The distribution of damage to
the log depends on the shape of the log.
However, to a very small virus in a mite on the head of a
termite in the center of the log, the shock waves from the
collissions would appear uniformly random in direction.
This is my theory for GRB. They are evidence of our universe
interacting with other universes! Why not! Makes
just as much sense as the GRB coming from the Oort cloud!
The log theory of universes can't be ruled out!
Of course, I'm a layman in the physics world. You
physicists out there, Tell me about this !!!!
Bob Combs
Astronautical Engineer,
Stanford Telecom
------------------------------
Date: Sat, 1 May 1993 02:53:39 GMT
From: "Phil G. Fraering" <pgf@srl03.cacs.usl.edu>
Subject: Gamma Ray Bursters How energetic could they be?
Newsgroups: sci.space,sci.astro
prb@access.digex.net (Pat) writes:
>In article <1rou8gINN7s4@gap.caltech.edu> palmer@cco.caltech.edu (David M. Palmer) writes:
>|prb@access.digex.com (Pat) writes:
>|
>|>In article <1993Apr26.200406.1@vax1.mankato.msus.edu> belgarath@vax1.mankato.msus.edu writes:
>|>|energetic for close by. for the coronal model, we found around 10^43 erg/sec.
>|>|And lastly, for the cosmological model an L=10^53. That's what you'd call
>|>|moderately energetic, I'd say. Any suggestions about what could put out that
>|>|much energy in one second?
>|>> -jeremy
>|
>|>big Capacitor :-) Real Big capacitor.
>|
>|It's been suggested. (Specifically, lightning strikes between clouds
>|in the interstellar medium.)
>|
>How big of a lightning rod, would you need for protection?
>and would you need jupiter as a ground plane.
>pat
Sounds to me like you'd want a star for the ground plane.
--
Phil Fraering |"Seems like every day we find out all sorts of stuff.
pgf@srl02.cacs.usl.edu|Like how the ancient Mayans had televison." Repo Man
------------------------------
Date: Fri, 30 Apr 1993 20:41:09 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: HST Servicing Mission Scheduled for 11 Days
Newsgroups: sci.space,sci.space.shuttle,sci.astro
In article <1rrgu7$9lp@access.digex.net> prb@access.digex.net (Pat) writes:
>>No, the thing is designed to be retrievable, in a pinch. Indeed, this
>>dictated a rather odd design for the solar arrays, since they had to be
>>retractable as well as extendable...
>
>Why not design the solar arrays to be detachable. if the shuttle is going
>to retunr the HST, what bother are some arrays...
They can be detached in an emergency. But expensive hardware is not thrown
away casually (bearing in mind that nobody knew the design was defective).
If the deployment crew had found some nasty flaw -- the lid failing to open,
for example -- it would have been a bit embarrassing to have to throw the
solar arrays away to get the thing back in the payload bay.
--
SVR4 resembles a high-speed collision | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS. - Dick Dunn | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: 30 Apr 1993 22:17:25 GMT
From: "David M. Palmer" <palmer@cco.caltech.edu>
Subject: HST Servicing Mission Scheduled for 11 Days
Newsgroups: sci.space,sci.space.shuttle,sci.astro
prb@access.digex.net (Pat) writes:
>In article <C6A2At.E9z@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>>
>>No, the thing is designed to be retrievable, in a pinch. Indeed, this
>>dictated a rather odd design for the solar arrays, since they had to be
>>retractable as well as extendable, and may thus have indirectly contributed
>>to the array-flapping problems.
>Why not design the solar arrays to be detachable. if the shuttle is going
>to retunr the HST, what bother are some arrays. just fit them with a quick
> release. one space walk, or use the second canadarm to remove the arrays.
You may want to put Hubble back in the payload bay for a reboost,
and you don't want to clip off the panels each time.
For the Gamma-Ray Observatory, one of the design requirements was that
there be no stored-energy mecahnisms (springs, explosive squibs, gas shocks,
etc.) used for deployment. This was partially so that everything could
be reeled back in to put it back in the payload bay, and partially for
safety considerations. (I've heard that the wings on a cruise missile
would cut you in half if you were standing in their swath when they opened.)
Back when the shuttle would be going up every other day with a cost to
orbit of $3.95 per pound :-), everybody designed things for easy servicing.
--
David M. Palmer palmer@alumni.caltech.edu
palmer@tgrs.gsfc.nasa.gov
------------------------------
Date: 30 Apr 1993 15:57:18 -0400
From: Pat <prb@access.digex.net>
Subject: HST Servicing Mission Scheduled for 11 Days
Newsgroups: sci.space,sci.space.shuttle,sci.astro
In article <1993Apr30.145450.1@stsci.edu> hathaway@stsci.edu writes:
>..
>>
>> After all the space walking, they are going to re-boost the HST's
>> orbit. I think right now it's sitting at 180 miles up,
>> they would like 220. I don't know the exact orbit numbers.
^^^^^^^^^^^^^^^^^^^^^^
>
>As Ben says - this re-boost idea is all news to us here. Do you know
>something we don't? Please supply a source - it would be nice for
>the schedulers of observations to know where the thing is going to
>be. These altitude numbers are also way off.
>
>My best source has:
>"Minimum ST ALTITUDE in the PMDB is: 573 Kilometers"
>"Maximum ST ALTITUDE in the PMDB is: 603 Kilometers"
>"Delta ST ALTITUDE in the PMDB is: 3 Kilometers"
>
>(PMDB is Proposal Management Data Base - used to schedule observations.)
>..
>
I am sure your numbers are far better then mine. As i said above,
i don't have exact numbers.
>> In order to perform the re-boost of the HST, the OMS engines
>> will be fired for a long period. Now the shuttle is a heavy
>> thing. THe HST isn't light either. THe amount of OMS fuel
>> needed to fly both up is substantial. a small booster
>> carried up and used to boost HST on it's own will weigh significantly
>> less then the OMS fuel required to Boost both HST and SHUttle,
>> for a given orbital change.
>>
>
>Could you supply some calculations? You might check some recent
>postings that explained that 'a small booster' as suggested does
>not now exist, so comparing the mass of something that doesn't
>exist to the mass of the OMS fuel seems impossible. The contamination
>threat also remains.
>
How different would the contamination threat of a small manuevering tug
be from that of the Shuttle and it's OMS engines??????
I know that no small manuevering tug exists, but maybe one could
soup up a Bus 1. Does anyone out there have the de-clasified
specs on hte BUS 1? would it be able to provide enough control
force to balance the HST, and still have the rocket thrust
to hurl her into a decent high orbit?
>..
>>
>> or the HST could even get placed into some sort of medium orbit.
>> The reason they want a high orbit, is less antenna pointing,
>> and longer drag life.
>>
> Longer drag life I can understand, but could you explain the
>antenna pointing?
Sorry, that should be intrument pointing.
>
>> Whatever it is, the problem in the tilt array is a big constraint
>> on HST ops.
>
>Tell me about it. Although the arrays can be (and are) moved perfectly
>well utilizing the second electronics box. Getting them both working
>is much desireable so as to reclaim redundancy.
Plus, if the second box gets fritzy, you could be in shitter ville
real fast.
>
>I don't mean to jump on you - helpful suggestions are always welcome
>and we all know the more ideas the better, but I do want the true
>situation to be described clearly and correctly, lest some get
>confused.
>
>Regards,
>Wm. Hathaway
The problem is no-one seems to have the exact numbers. When the mission
was planned originally at 3 spacewalks, and 3 astronauts, there was
enormous concern over the mass margins for the flight. THey
have now planned for 5 EVA's, an 11 day mission and have 2 reserve
EVA's and an emergency EVA. Obviously that is coming from somewhere.
My guess is the OMS burn fuel, or re-boost margin.
I just figured, if GOldin wants to really, prove out faster, cheaper
better, have some of the whiz kids slap together an expendable
space manuevering tug out of a BUs1, and use that for the re-boost.
it has to be better then using the Discovery as a tow truck.
pat
------------------------------
Date: Fri, 30 Apr 1993 19:35:07 GMT
From: "Don M. Gibson" <dong@oakhill.sps.mot.com>
Subject: Long term Human Missions
Newsgroups: sci.space,sci.space.shuttle,sci.astro
In article 290493130832@128.249.27.63, jgladu@bcm.tmc.edu (grungy) writes:
>ward@pashosh.wisdom.weizmann.ac.il (Ward Paul) wrote:
>> >1. Calculators
>> >2. Teflon (So your eggs don't stick in the pan)
>> >3. Pacemakers (Kept my grandfather alive from 1976 until 1988)
>>
>I think we *should* tell them about the things that they are using now that
>are spinoffs of the space program. That is the only way you can *prove*
>its worth to *them* - and they vote and pay taxes too. The continued
>existence of the space program relies upon that money.
>
>just my $.02
>
>BTW: don't forget Velcro...
at least be honest. velcro (tm) dates from the 40's. i have doubts
about everything listed above. just because it was developed in the
space age, doesn't mean it was a space spin-off.
BTW: don't forget Tang...:)
-DonG
------------------------------
Date: 30 Apr 1993 17:52:24 -0700
From: Ken Hayashida <khayash@hsc.usc.edu>
Subject: Long Term Space Voyanges and Effect NEwsgroup?
Newsgroups: sci.space
tstroup@force.ssd.lmsc.lockheed.com writes in response to my original post:
>First you need to do the literature search. There is a lot of information
>out there. Maybe we should just pick a specific area of long term habitation.
>This could be useful, especially if we make it available on the net. Then
>we can look at methods of analyzing the technologies.
>>Such a detailed literature search would be of interest to
>>ourselves as space advocates
>>and clearly important to existing space programs.
>>In essence, we would be dividing the space life science issues into
>>various technical problems which could be solved with various technologies.
>>This database of acceptable solutions to various problems could form the
>>basis of detailed discussions involving people from the bionet, isunet,
>>and any other source!
>Unless there is an unbelievable outpouring of interest on this on the net,
>I think we should develop a detailed data base of the literature search
>first. Then if we accomplish that we can go on to real analysis. The data
>base itself could be useful for future engineers.
>That's my response Ken, what do you think?
>Tim
Well, I agree. I hope others chime in with suggestions on specific
technologies which could be applied towards the maintenance of an
Earth like atmosphere on a long-duration spacecraft.
Tim et al:
I think we should try looking at atmosphere first.
This seems to be the single most fundamental issue in keeping anyone alive.
We're all taught that when supporting a patient
you look for maintaining airway. So, in keeping with my trauma training
(and keeping my emergency medicine professor happy), I suggest that
we look at the issues surrounding a regenerable atmospheric circuit.
Howz that Tim?
Ken
------------------------------
Date: 30 Apr 1993 20:58 UT
From: Ron Baalke <baalke@kelvin.jpl.nasa.gov>
Subject: Mars Observer Update - 04/30/93
Newsgroups: sci.space,sci.astro,alt.sci.planetary
Forwarded from the Mars Observer Project
MARS OBSERVER STATUS REPORT
April 30, 1993
11:30 AM PDT
DSS-65 (Madrid 34 meter antenna) did not acquire the expected Mars Observer
Spacecraft signal at the scheduled beginning of track yesterday morning (4/29)
at approximately 6:00 AM. Indications were that the spacecraft had entered a
Fault Protection mode sometime between that time and receipt of normal
telemetry at the end of the previous station pass (DSS-15 - Goldstone 34
meter antenna) at approximately 8:00 PM the evening before. Entry into
Contingency Mode was verified when signal was reacquired and telemetry
indicated that the spacecraft was sun coning. After subsystem engineers
reported all systems performing nominally, fault protection telemetry modes
were reconfigured and memory readouts of command system Audit Queue and
AACS (Attitude and Articulation Control Subsystem) Starex performed. These
readouts verified that Contingency Mode entry occurred shortly after 1:30 AM
yesterday, 4/29/93. Preliminary indications are that a Sun Ephemeris Check
failure triggered fault protection. However, the Flight Team will be
determining the precise cause over the next few days.
As of last evening, the spacecraft had been commanded back to Inertial
Reference and was stable in that mode. The Flight Team is planning to
command the spacecraft back to Array Normal Spin state today.
Magnetometer Calibration activities had completed prior to Contingency
Mode entry. MAG Calibration data has been recorded on Digital Tape
Recorders 2 and 3. Playback of DTRs 2 and 3, scheduled to be completed
yesterday, was postponed when Contingency Mode entry halted Flight
Sequence C9 execution. The Flight Team is developing a strategy to restart
C9 to complete data playback. Present planning is to perform playbacks
between as soon as Wednesday, or as late as Friday of next week (5/5-
5/7), dependent on Contingency Mode recovery activity. DTR playback will
be performed via the High Gain Antenna at 42,667 bits per second. Upon
verification of successful DTR playbacks, downlink will be maintained at
the 4K S & E rate.
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | The aweto from New Zealand
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | is part caterpillar and
|_____|/ |_|/ |_____|/ | part vegetable.
------------------------------
Date: Sat, 1 May 1993 01:32:58 GMT
From: "William E. O'Shaughnessy" <billosh@netcom.com>
Subject: moon image in weather sat image
Newsgroups: sci.astro,sci.space,sci.geo.meteorology,sci.geo.geology
If you brighten up the dark part of CV043015.GIF with your viewer you
will see two other objects near the upper left part of the moon.
One is actually between the weather satellite and the moon.
Bill O'Shaughnessy
------------------------------
Date: 30 Apr 93 16:43:26 CDT
From: Bob Kierski <bobo@thejester.cray.com>
Subject: Philosophy Quest. How Boldly?
Newsgroups: sci.space
In article <C6Assy.Ao9@fs7.ece.cmu.edu>, loss@fs7.ECE.CMU.EDU (Doug Loss) writes:
> Analog SF magazine did an article on a similar subject quite a few
> years ago. The question was, if an alien spacecraft landed in
> Washington, D.C., what was the proper organization to deal with it: The
> State Department (alien ambassadors), the Defense Department (alien
> invaders), the Immigration and Naturalization Service (illegal aliens),
> the Department of the Interior (new non-human species), etc. It was
> very much a question of our perception of the aliens, not of anything
> intrinsic in their nature. The bibliography for the article cited a
> philosophical paper (the name and author of which I sadly forget; I
> believe the author was Italian) on what constitutes a legal and/or moral
> person, i.e., a being entitled to the rights normally accorded to a
> person. The paper was quite interesting, as I recall.
This is a whole different situation. If aliens were able to get here prior
to us being able to get there, one might conclude that they would be more advanced
and therefore "more intelegent" that we are. However if we get somewhere where there
is life, chances are we wont be able to communicate with them. So we will have
no clue as to weather they are "intelegent" or not.
> I think you'd have to be very careful here if the answer is yes. The
> human track record on helping those poor underpriveleged cultures (does
> underpriveleged mean not having enough priveleges?) is terrible. The
> usual result is the destruction or radical reorganization of the
> culture. This may not always be wrong, but that's the way to bet.
That's a good point, I hadn't thought of it that way. My question however was
more along the lines of... Every year the US spends millions of tax dollars
and giving tax breaks to individuals and companies who feed the poor of foreign
countries while thousands of our own people sleep on the streets at night.
Would we give to the economicly dissadvantaged on another planet if we hadn't resolved
these issues on our own?
But... Your comment brings up another good question. Over the years we have decided
that certain cultures need improvements. The native americans is a good example. Prior
to our attempt to civilize them, the native american culture had very little crime, no
homelessnes, no poverty. Then the europeans came along and now they have those and
more. If we encounter life elsewhere, do we tell them they have to live in houses, farm
the land and go to church on sunday?
--
Have a day,
@ @
( ) bobo
------------------------------
Date: 30 Apr 93 18:27:41 -0600
From: Bill Higgins-- Beam Jockey <higgins@fnalf.fnal.gov>
Subject: Revival of San Marco? (was Re: Commercial Space News #22)
Newsgroups: sci.space
In article <324417a1@ofa123.fidonet.org>, Wales.Larrison@ofa123.fidonet.org writes:
> COMMERCIAL SPACE NEWS/SPACE TECHNOLOGY INVESTOR NUMBER 22
[...]
> This might point out some key discriminators in judging the
> feasibility of a commercial launch site. These include:
> - Is there an identified key customer to provide core usage
> sufficient to recover setup costs?
> - Is there a market advantage of using the site?
> - Can existing infrastructure be used or modified at the site?
> - Can financing be found at low enough cost to support the
> investment?
> Other commercial launch site ventures -- including those at
> Woomera, Poker Flat, Cape York, White Sands, Alabama Off-Shore
> Platform, Hawaii, and Vandenberg have to also be judged against
> these criteria. In my opinion, some of these ventures are flying
> on hope and speculation, and not on sound financial grounds.]
This reminds me... my fuzzy brain recalls that somebody was thinking
of reviving the San Marco launch platform off the coast of Kenya,
where the Copernicus satellite was launched around 1972. Is this
true, or am I imagining it? Possibly it's connected with one of the
Italian programs to revive the Scout in a new version.
That old platform must be getting pretty rusty, and there ain't a lot
of infrastructure to go with it...
Bill Higgins, Beam Jockey | "We'll see you
Fermi National Accelerator Laboratory | at White Sands in June.
Bitnet: HIGGINS@FNAL.BITNET | You bring your view-graphs,
Internet: HIGGINS@FNAL.FNAL.GOV | and I'll bring my rocketship."
SPAN/Hepnet: 43011::HIGGINS | --Col. Pete Worden on the DC-X
------------------------------
Date: 30 Apr 1993 21:17 UT
From: Ron Baalke <baalke@kelvin.jpl.nasa.gov>
Subject: Satellite around Pluto Mission?
Newsgroups: sci.space
In article <1993Apr30.004311.1@aurora.alaska.edu>, nsmca@aurora.alaska.edu writes...
>
>Is there a plan to put a satellite around each planet in the solar system to
>keep watch? I help it better to ask questions before I spout an opinion.
We've been progressing towards that goal for 30 years now. We precede
any orbiting mission with flyby missions. Of course, it gets harder to
do as we work our way farther away from Earth. We're just starting to
work out to the outer planets: Galileo will orbit Jupiter, and Cassini around
Saturn.
>How about a mission (unmanned) to Pluto to stay in orbit and record things
>around and near and on Pluto..
Well first things first. We'll do a flyby mission first since it is
much easier and faster to do. If the Fast Pluto Flyby mission is approved then
we'll launch a Pluto mission before the end of the decade. A Pluto orbiter
however requires a larger spacecraft and a longer cruise period. Orbit
insertion requires more fuel has to be carried along and restricts the
trajectory to a slower approach velocity to Pluto.
I'd imagine though that we would be doing a Neptune orbiting
mission before a Pluto orbiting mission, unless the Pluto flyby turns
up something really interesting.
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | The aweto from New Zealand
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | is part caterpillar and
|_____|/ |_|/ |_____|/ | part vegetable.
------------------------------
Date: 30 Apr 1993 20:09:17 GMT
From: Andy Cohen <Cohen@ssdgwy.mdc.com>
Subject: Single Launch Space Station
Newsgroups: sci.space
In article <C69qA6.J4w.1@cs.cmu.edu>, 0004244402@mcimail.com (Karl Dishaw)
wrote:
>
> Andy Cohen <Cohen@ssdgwy.mdc.com> writes:
> >the Single Launch Core Station concept. A Shuttle external tank and solid
> >rocket boosters would be used to launch the station into orbit. Shuttle
> >main engines would be mounted to the tail of the station module for launch
> >and jettisoned after ET separation.
>
> Why jettison the SSMEs? Why not hold on to them and have a shuttle
> bring them down to use as spares?
Good question....I asked that myself....However, since this option is as
expensive as the Freedom derivative, the issue will likely be moot.
------------------------------
Date: Fri, 30 Apr 1993 21:39:44 GMT
From: TS Kelso <tkelso@afit.af.mil>
Subject: Two-Line Orbital Element Set: Space Shuttle
Newsgroups: sci.space
The most current orbital elements from the NORAD two-line element sets are
carried on the Celestial BBS, (513) 427-0674, and are updated daily (when
possible). Documentation and tracking software are also available on this
system. As a service to the satellite user community, the most current
elements for the current shuttle mission are provided below. The Celestial
BBS may be accessed 24 hours/day at 300, 1200, 2400, 4800, or 9600 bps using
8 data bits, 1 stop bit, no parity.
Element sets (also updated daily), shuttle elements, and some documentation
and software are also available via anonymous ftp from archive.afit.af.mil
(129.92.1.66) in the directory pub/space.
STS 55
1 22640U 93 27 A 93120.24999999 .00044939 00000-0 12819-3 0 129
2 22640 28.4643 241.8868 0011265 284.7181 109.3644 15.91616537 580
--
Dr TS Kelso Assistant Professor of Space Operations
tkelso@afit.af.mil Air Force Institute of Technology
------------------------------
Date: Fri, 30 Apr 1993 20:42:23 GMT
From: Josh Hopkins <jbh55289@uxa.cso.uiuc.edu>
Subject: Vandalizing the sky.
Newsgroups: sci.astro,sci.space
rbunge@access.digex.net (Robert Bunge) writes:
>In article <C69AGI.MJu@news.cso.uiuc.edu> jbh55289@uxa.cso.uiuc.edu (Josh Hopkins) writes:
>>I'm wondering if "vandalize" is the proper word to use in this situation. My
>>dictionary defines "vandalism" as "the willful or malicious destructuion of
>>public or private property, especially of anything beautiful or artisitc." I
>>would agree the sky is beautiful, but not that it is public or private property.
>It's public because it belongs to everybody.
No, the sky does not, at this time, belong to anyone. Ownership is necessary
to the definition because someone has to have the authority to decide if the
action was good or bad. If neither you or I own a brick wall, then I can't
unilaterally declare that spraypainting my name on it is right, and you don't
have the authority to declare that it is wrong. The owner may find it artistic
or she may be call the police.
(this applies to the argument on bright satellites more than street lights)
It's vandalism because many people -- power companies -- do maliciously waste light.
"maliciously" implies evil intent. The lighting companies aren't going out
of their way to spoil the sky. They just don't care.
>If they can sell you
>or your city or your state an unshielded light that wastes 30 to 50 percent
>of its light, they make more _money_. Never mind that your money is wasted.
It is the responsibility of the customer to choose the most efficient hardware.
If that's what your city will buy, that's what the lighting company will sell.
Write a letter to city hall.
Please note that I'm not defending light pollution. The orignial focus of
this thread was space based light sources.
--
Josh Hopkins jbh55289@uxa.cso.uiuc.edu
"Find a way or make one."
-attributed to Hannibal
------------------------------
Date: Fri, 30 Apr 1993 20:33:30 GMT
From: Dillon Pyron <pyron@skndiv.dseg.ti.com>
Subject: What planets are habitable
Newsgroups: sci.space
In article <C6Az8z.pD@zoo.toronto.edu>, henry@zoo.toronto.edu (Henry Spencer) writes:
>In article <1rpt1v$q5h@hsc.usc.edu> khayash@hsc.usc.edu (Ken Hayashida) writes:
>>As for human tolerances, the best example of human endurance in terms
>>of altitude (i.e. low atmospheric pressure and lower oxygen partial pressure)
>>is in my opinion to the scaling of Mt. Everest without oxygen assistance...
>>... This is quite a feat of physiological endurance...
>
>Indeed so; it's at the extreme limit of what is humanly possible. It is
>possible only because Mount Everest is at a fairly low latitude: there
>is a slight equatorial bulge in the atmosphere -- beyond what is induced
>by the Earth's rotation -- thanks to the overall circulation pattern of
>the atmosphere (air cools at poles and descends, flowing back to equator
>where it is warmed and rises), and this helps just enough to make Everest-
>without-oxygen feasible. Only just feasible, mind you: the guys who did
>it reported hallucinations and other indications of oxygen starvation,
>and probably incurred some permanent brain damage.
Climbers regard 8000 metres and up as "The Death Zone". Even on 100% Oxygen,
you are slowly dying. At 8848m (Everest), most climbers spend only a short
period of time before descending. I've been above 8000 once. Descending as
little as 300m feels like walking into a jungle, the air is so thick. Everest
in winter without oxygen, no support party (Alpine style). That is the
"ultimate challenge" (or is it solo?)
--
Dillon Pyron | The opinions expressed are those of the
TI/DSEG Lewisville VAX Support | sender unless otherwise stated.
(214)462-3556 (when I'm here) |
(214)492-4656 (when I'm home) |Texans: Vote NO on Robin Hood. We need
pyron@skndiv.dseg.ti.com |solutions, not gestures.
PADI DM-54909 |
------------------------------
From: Andy Cohen <Cohen@ssdgwy.mdc.com>
Newsgroups: sci.space
Subject: Re: Space Station Redesign, JSC Alternative #4
Followup-To: sci.space
Date: 30 Apr 1993 20:12:36 GMT
Organization: MDA-W
Lines: 42
Distribution: world
Message-Id: <Cohen-300493131452@q5022531.mdc.com>
References: <1993Apr23.184732.1105@aio.jsc.nasa.gov> <23APR199317452695@tm0006.lerc.nasa.gov> <1ralibINNc0f@cbl.umd.edu> <1993Apr27.092444.27199@ee.ubc.ca>
Nntp-Posting-Host: q5022531.mdc.com
Sender: news@CRABAPPLE.SRV.CS.CMU.EDU
Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU
In article <1993Apr27.092444.27199@ee.ubc.ca>, davem@ee.ubc.ca (Dave
Michelson) wrote:
>
> In article <1ralibINNc0f@cbl.umd.edu> mike@starburst.umd.edu (Michael F. Santangelo) writes:
> >dbm0000@tm0006.lerc.nasa.gov (David B. Mckissock) writes:
> >
> >...text of options "A" and "B" deleted...
> >
> >>Option C - Single Core Launch Station.
> >>This is the JSC lead option. Basically, you take a 23 ft diameter
> >>cylinder that's 92 ft long, slap 3 Space Shuttle Main Engines on
> >>the backside, put a nose cone on the top, attached it to a
> >>regular shuttle external tank and a regular set of solid rocket
> >>motors, and launch the can. Some key features are:
> >> - Complete end-to-end ground integration and checkout
> >> - 4 tangentially mounted fixed solar panels
> >> - body mounted radiators (which adds protection against
> >> micrometeroid & orbital debris)
> >> - 2 centerline docking ports (one on each end)
> >> - 7 berthing ports
> >> - a single pressurized volume, approximately 26,000 cubic feet
> >> (twice the volume of skylab).
> >> - 7 floors, center passageway between floors
> >> - 10 kW of housekeeping power
> >
> >Somehow I have a strange attraction for this idea (living in
> >a modular home maybe has altered my mind). The only thing
> >that scares me is the part about simply strapping 3 SSME's and
> >a nosecone on it and "just launching it." I have this vision
> >of something going terribly wrong with the launch resulting in the
> >complete loss of the new modular space station (not just a peice of
> >it as would be the case with staged in-orbit construction).
>
> I certainly like this "Option C"... It's much more like the original
> Phase B studies from the early 1970's. Good stuff!
This is actually more like the stuff from Phase A and MOL....Phase B ended
with a "Power Tower" approach....
It's also VERY expensive in terms of upfront development costs....so all
you get is a redistribution of costs from the shuttle flights to the
contractors who build it.
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End of Space Digest Volume 16 : Issue 511
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