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Date: Sun, 28 Feb 93 05:02:28
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V16 #232
To: Space Digest Readers
Precedence: bulk
Space Digest Sun, 28 Feb 93 Volume 16 : Issue 232
Today's Topics:
Apollo Moon Missions ?
Beamed power transmission on Mars? (2 msgs)
Blimps, Hindenburg, Mars, Beamed power.
Canadian SSF effort ??
E-MAIL PENPAL LIST
Elements -> AZ,ELEV
extreme responses to Challenger transcript
Fallen Angels
Freedom refueling
Getting people into Space Program!
How to power the LEO-moon space bus : ) (2 msgs)
Nobody cares about Fred?
Spaceflight for under $1,000? (3 msgs)
Spy Sats (Was: Are Landsat Satellites receivable?)
Welcome to the Space Digest!! Please send your messages to
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----------------------------------------------------------------------
Date: 25 Feb 1993 05:21 UT
From: Ron Baalke <baalke@kelvin.jpl.nasa.gov>
Subject: Apollo Moon Missions ?
Newsgroups: sci.space
In article <1mh72oINNdu8@elroy.jpl.nasa.gov>, tjt@Jpl.Nasa.Gov writes...
> I am ignorant, I admit it. My memory has failed. Can someone refresh my
>tired brain cells, and tell me (us) which Apollo mission to the Moon was the
>last one? There couldn't have been too many.
YO!! TIM!!
It was Apollo 17 in 1972.
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | If you don't stand for
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | something, you'll fall
|_____|/ |_|/ |_____|/ | for anything.
------------------------------
Date: Thu, 25 Feb 1993 09:51:39 GMT
From: Dave Garnett <dg@cam-orl.co.uk>
Subject: Beamed power transmission on Mars?
Newsgroups: sci.space
>> suggestion for use of beamed microwave power ...
Why not just beam down sunlight, and do all the conversion etc
(or even heating your balloon) locally ? Increase the local
'sunlight' by ten times, you get ten times more power out of
your solar cells ! You would have to be a little careful to
avoid concentrating power too much, but the same is true for
microwaves etc.
The advantage is a very simple system in space - just a guided
mirror, and ground systems which you would probably need anyway.
The only real question is how much dust storms would obscure
the beam - are there any measurements on this ?
Dave Garnett
------------------------------
Date: 25 Feb 93 13:14:08 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Beamed power transmission on Mars?
Newsgroups: sci.space
In article <rabjab.39.730491211@golem.ucsd.edu> rabjab@golem.ucsd.edu (Jeff Bytof) writes:
>I was wondering if it would be worth considering a power source
>for future human exploration of Mars that used a solar radiation
>collector in Mars orbit and beamed microwaves or lasers to receivers
>on the surface. Perhaps the laser option would work best as the
>size of the receiving antenna would be smaller and perhaps highly
>portable. That way, much longer traverses away from the central
>base might be possible, decreasing the amount of fuel the rovers would
>have to carry along.
Converting radient energy, microwaves or laser beams, back into
useful propulsive power for a small mobile vehicle is the bane
of any such plan. Microwave rectennas are up to the task, but
the required focusing from orbit is incredibly difficult for a
portable ground array. Lasers make a tight enough beam, but there's
no really compact or efficient way to convert the light to electricity.
On board nuclear power is much better for this purpose and completely
sidesteps issues of line of sight scheduling and complex systems in
orbit with single point failure modes that can disable an entire ground
fleet of vehicles and habitations.
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244 | |
------------------------------
Date: 25 Feb 93 06:11:43 GMT
From: nsmca@acad3.alaska.edu
Subject: Blimps, Hindenburg, Mars, Beamed power.
Newsgroups: sci.space
In article <1993Feb25.024619.22024@ucsu.Colorado.EDU>, fcrary@ucsu.Colorado.EDU (Frank Crary) writes:
> In article <d2gC02Lb37wk01@JUTS.ccc.amdahl.com> haw30@macaw.ccc.amdahl.com (Henry A Worth) writes:
>> You could even vary flux to match activity. Transmitting at a higher
>>flux when personnel are in shielded vehicles and on the move (just when
>>you have highest demand! -- hey, microwave heated, hot gas blimps!, is the
>>Martian atomosphere dense enough?)
>
> Balloons are somewhat more difficult on Mars than on Earth, but they
> are very feasible. There will be one on the Russian Mars 94 mission
> (or so they say...)
>
> Frank Crary
> CU Boulder
>
I more like rigid balloons (deridgebles(sp)). Powered by beamed microwaves
either from the ground or from orbit..
Don't need to beam power directly at the Blimp, just to the tether that follows
behind..
==
Michael Adams, nsmca@acad3.alaska.edu -- I'm not high, just jacked
------------------------------
Date: 24 Feb 93 13:23:39 GMT
From: Paul Johnson <paj@uk.co.gec-mrc>
Subject: Canadian SSF effort ??
Newsgroups: sci.space
In article <1993Feb19.185606.23871@colorado.edu> loucks@csn.org (Lord Vader) writes:
>WASHINGTON POST - NASA Administrator Daniel Goldin ended
>weeks of rumors yesterday with an announcement that President
>Clinton has directed him to "redesign" the planned space
>station to make it more efficient and useful.
>"...streamlined, cost-effective design..."
You mean its currently inefficient, useless and not cost-effective?
Why?
Or is this just going to make "Fred" into "Fud"?
Paul.
--
Paul Johnson (paj@gec-mrc.co.uk). | Tel: +44 245 73331 ext 3245
--------------------------------------------+----------------------------------
These ideas and others like them can be had | GEC-Marconi Research is not
for $0.02 each from any reputable idealist. | responsible for my opinions
------------------------------
Date: 24 Feb 93 18:51:00 GMT
From: Trish Rucker <trish.rucker@kingsp.gwinnett.com>
Subject: E-MAIL PENPAL LIST
Newsgroups: sci.space
E-MAIL PENPAL MAILING LIST
Interested in corresponding with penpals via e-mail?
I'm compiling a quarterly (January, April, July,
October) mailing list of people who would like to have e-mail
pals.
If you'd like to be on the mailing list, please complete
the following questionnaire and send it back to me via
Internet (trish.rucker@ehbbs.gwinnett.com).
Internet Address:
Name:
City:
State:
Age:
Date of Birth:
Sex:
Occupation:
If Student, College Major:
Hobbies and Interests:
Only replies sent via Internet will be honored. I'm
looking forward to hearing from you soon!
trish.rucker@ehbbs.gwinnett.com
----
+------------------------------------------------------------------------+
| The King's Palace BBS * Canton, GA * (404) 781-8435 * USR DS |
| Paul Gamber and Paul Gamber III, Sysops * kingsp@gwinnett.com |
+------------------------------------------------------------------------+
------------------------------
Date: 24 Feb 93 20:24:51 GMT
From: Bruce Watson <wats@scicom.AlphaCDC.COM>
Subject: Elements -> AZ,ELEV
Newsgroups: sci.space,sci.astro
In article <86220@hydra.gatech.EDU| gt4609c@prism.gatech.EDU (Scott Coffeen) writes:
|Hello.
|
| I am looking for a book of equations necessary to convert satellite orbital
|elements into azimuth and elevation. I can't use a computer, I must work it
|all out by hand (That's what college is all about!) I was wondering if there
|was a book by NASA on the subject. I checked the FAQ but I really didn't see
|anything that helped.
|
What did you do to get such a cruel assignment? :-)
To get the mathematical details consult just about any book on celestial
mechanics or astrodynamics in the TL700s or QB300s. The method was known long
before NASA was formed.
Sadly, I've yet to come across a book that spelled it out plainly, even in
chapters named ephemeris generation. Here are the steps:
(1) Convert geodetic latitude of observer to geocentric latitude.
(2) Choose a date and time and convert it to Julian Date or Modified JD.
(3) Compute Greenwich hour angle for date and time.
(4) Rotate earth so that observer is in the right position in space.
(5) Compute mean anomaly from mean motion and date and time.
(6) Compute eccentric anomaly using Kepler's equation by iteration.
(7) Compute true anomaly from eccentric anomaly.
(8) Apply perturbations to RA of ascending node and argument of perigee.
(9) Find satellite's rectangular coordinates from spherical coordinates.
(10) Similarly find observer's rectangular coordinates.
(11) Subtract the above two vectors.
(12) Rotate the result to observer's topocentric coordinates.
(13) Compute satellite altitude and azimuth.
(14) If altitude is less than zero go back to step (2) and repeat.
It's a good exercise involving matrix algebra, numerical analysis and
spherical geometry. Good luck.
--
Bruce Watson (wats@scicom.alphaCDC.COM) Bulletin 629-49 Item 6700 Extract 75,131
------------------------------
Date: Thu, 25 Feb 1993 14:03:05 GMT
From: Franz Pirker <fzp@ipp-garching.mpg.de>
Subject: extreme responses to Challenger transcript
Newsgroups: sci.space,sci.astro,alt.privacy,comp.org.eff.talk
In article <C2944A.E1q@cs.uiuc.edu> kadie@cs.uiuc.edu (Carl M. Kadie) writes:
>Xref: informatik.tu-muenchen.de sci.space:42826 sci.astro:26283 alt.privacy:5653 comp.org.eff.talk:14098
>Newsgroups: sci.space,sci.astro,alt.privacy,comp.org.eff.talk
>Path: informatik.tu-muenchen.de!lrz-muenchen.de!fauern!ira.uka.de!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!uwm.edu!ux1.cso.uiuc.edu!cs.uiuc.edu!kadie
>From: kadie@cs.uiuc.edu (Carl M. Kadie)
>Subject: Re: extreme responses to Challenger transcript
>Message-ID: <C2944A.E1q@cs.uiuc.edu>
>Organization: University of Illinois, Dept. of Comp. Sci., Urbana, IL
>References: <1993Feb3.021308.6018@fuug.fi> <1knhm2INNfti@transfer.stratus.com> <C1vn9H.4u9@cs.uiuc.edu> <C277Go.MKC@wang.com>
>Distribution: inet
>Date: Wed, 10 Feb 1993 21:09:45 GMT
>Lines: 25
>kadie@cs.uiuc.edu (Carl M. Kadie) writes:
>
>>There is no such a crime as libel against the government (i.e.
>>seditious libel) in the U.S. anymore.
>
>dbushong@wang.com (Dave Bushong) writes:
>
>>Whether or not that's true, it doesn't necessarily mean that it's not
>>libelous. Libel is "a written, printed, or pictorial statement that
>>damages a person by defaming his character or reputation, damaging
>>him in his occupation, or exposing him to public ridicule." It
>>doesn't say that it is a crime.
>
>The government is not a person.
>
>Anyway, "libel" has multiple meanings. The 4th definition in Webster's
>9th Collegiate is "the act, tort, or crimt of publishing such a
>libel".
>
>- Carl
>
>
>--
>Carl Kadie -- I do not represent any organization; this is just me.
> = kadie@cs.uiuc.edu =
------------------------------
Date: 25 Feb 93 13:01:26 GMT
From: FRANK NEY <tnc!m0102>
Subject: Fallen Angels
Newsgroups: sci.space,sci.energy,rec.arts.sf.fandom
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?
The story itself has much to recommend it and I would urge others to
read it. It describes the story of two astronauts shot down over the
US, after the turn of the century where the greens and the politically
(in-)correct have taken over.
The astronauts are rescued and returned to their space station (using
PHOENIX prototype) through the efforts of SF Fandom and the SCA. Very
entertaining and quite thought-provoking.
Frank Ney N4ZHG EMT-A NRA ILA GOA CCRTKBA "M-O-U-S-E"
Commandant and Acting President, Northern Virginia Free Militia
Send e-mail for an application and more information
----------------------------------------------------------------
"Whether the authorities be invaders or merely local tyrants, the
effect of such [gun] laws is to place the individual at the mercy of
the state, unable to resist."
- Robert Heinlein, in a 1949 letter concerning "Red Planet"
--
The Next Challenge - Public Access Unix in Northern Va. - Washington D.C.
703-803-0391 To log in for trial and account info.
------------------------------
Date: Thu, 25 Feb 1993 03:24:07 GMT
From: Frank Crary <fcrary@ucsu.Colorado.EDU>
Subject: Freedom refueling
Newsgroups: sci.space
In article <C2z9KI.4yL@news.cso.uiuc.edu> jbh55289@uxa.cso.uiuc.edu (Josh Hopkins) writes:
>>>Again, it's not the lack of EVA, it's the fact that you don't want
>>>hydrazine all over the EVA crew.
>>But the Russians with their backward space program don't find that to
>>be a problem. Surely with our better technology we could refuel them
>>in orbit possible saving billions of $$ in life cycle cost.
>Allen, could you (or perhaps Dennis Newkirk) post a description of just how the
>Russians refuel Mir?
They have a modified, unmanned version of their Soyuz crew transport called
Progress. The crew compartment replaced by extra fuel tanks, and
an automatic navigation/docking system. The orbital compartment
(intended to provide additional room for on-orbit crew activities
in the manned Soyuz) is filled instead with consumables. The docking
collar is modified (as is the aft docking port on Mir/Kvant) to connect
fuel pipes as well as the main pressurized hatch for crew access.
A Progress is launched and automatically docks to the rear docking
port of the station. After checking to make sure the fuel pipes are
connected properly (done by mission control in Kalingrad, not by
the station crew, I believe), the fuel in the Progress'
tanks is transfered directly to the station keeping tanks of the
station. The crew then (sometimes several days later...) opens
the main hatch between the Progress and the station, and unloads
by hand the (non-fluid) consumables. All is all, the process
requires about one day of crew work (no EVA) for a month's
worth of supplies. Since the Progress also has it's own
maneuvering rockets, it can also act as a "tug" while docked
to the station (e.g. if the station's own motors are broken.
This was done with Salyut 7 for the second half of that station's
operating life.)
>>>I don't think the OMS are big enough to fuel both orbiter and SSF.
>>Well then maybe they can be refueled with expendables. That will save
>>even more money.
>Freedom would have weighed roughly five times as much as shuttle and shuttle
>needs its OMS fuel to get back home. In light of this, I can't figure out what
>your last comment means.
I think he is suggesting taking the Shuttle out of the picture entirely.
Frank Crary
CU Boulder
------------------------------
Date: 25 Feb 93 13:24:42 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Getting people into Space Program!
Newsgroups: sci.space
In article <1mduk3INNb9v@access.digex.com> prb@access.digex.com (Pat) writes:
>In article <1993Feb22.222529.9297@ee.ubc.ca> davem@ee.ubc.ca (Dave Michelson) writes:
>| ----------------------------------
>| 199 19
>| ----------------------------------
>|
>|Of 12 X-15 pilots, it appears that 8 earned astronaut wings.
>
>
>I didn't realize the percentage of "Space" X-15 fligts were so low.
>But the basic concept still stands. That A "Research" vehicle
>undergoing a "Dynamic test routine" was able to maintain an
>average flight level higher then a "Operational" shuttle system.
>And that said research vehicle was able to achieve regular routine
>access to space. Granted tehy are two entirely difficult vehicles,
>but it si only lately, 33 some years after the x-15 flew that
>the STS is able to achieve a flight rate vaguely like the x-15.
>Sortie rates are very important from an operations viewpoint,
>and the shuttle has had a great deal of difficulty achieving
>a reasonable sorty rate.
Wait a minute. Over a 9 year period, 19 flights above 50 miles
with a duration of under 5 minutes each carrying a total of 8
"astronauts" and *no* payload is equivalent to Shuttle's 52+
flights, in 12 years with a 2 year layoff, carrying over 350
people to *orbit* for stays up to 7 days and carrying up to
40,000 pounds of payload on each flight? I think not. That's
like trying to compare a dugout canoe to a supertanker.
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244 | |
------------------------------
Date: Thu, 25 Feb 1993 10:34:11 GMT
From: "Herity D." <dherity@cs.tcd.ie>
Subject: How to power the LEO-moon space bus : )
Newsgroups: sci.space
henry@zoo.toronto.edu (Henry Spencer) writes:
>In article <1993Feb24.005220.15641@bsu-ucs> 01crmeyer@leo.bsuvc.bsu.edu (Craig Meyer) writes:
>>When it comes to frieght runs back and forth from LEO to the moon, NUCLEAR
>>PROPULSION SYSTEMS look like the way to go. A few Uranium spheres will take
>>you a long way, along with a little hydrogen gas as a working fluid...
>Unfortunately, it's more than a little hydrogen, at least with near-future
>nuclear systems.
Also, an aerobraking nuclear rocket might not be too popular with the people
under the flightpath. If you leave out aerobraking to LEO, the nuclear option
loses much of its attraction compared to a chemical rocket using aerobraking.
--
-----------------------------------------------------------|"Nothing travels |
| Dominic Herity, dherity@cs.tcd.ie, |faster than light, |
|Computer Science Dept, Trinity College, Dublin 2, Ireland.|except possibly bad|
| Tel : +353-1-6772941 ext 1720 Fax : +353-1-6772204 |news"-Douglas Adams|
------------------------------
Date: Thu, 25 Feb 1993 10:37:50 GMT
From: "Herity D." <dherity@cs.tcd.ie>
Subject: How to power the LEO-moon space bus : )
Newsgroups: sci.space
fcrary@ucsu.Colorado.EDU (Frank Crary) writes:
>>When it comes to frieght runs back and forth from LEO to the moon, NUCLEAR
>>PROPULSION SYSTEMS look like the way to go. A few Uranium spheres will take
>>you a long way, along with a little hydrogen gas as a working fluid. As long
>>as the thing never came back to earth, radiation wouldn't be nearly as
>>much of a problem.
>Given the elements available on the surface, oxygen might be a better
>option: The specific impulse would drop to 25% of a hydrogen fueled
>nuclear thremal rocket, and nasty corrosion problems might crop up,
>but refueling on the Lunar surface would be very easy.
I suspect you'd be better off bringing a tank of hydrogen to burn with the
oxygen, rather than a nuclear engine.
--
-----------------------------------------------------------|"Nothing travels |
| Dominic Herity, dherity@cs.tcd.ie, |faster than light, |
|Computer Science Dept, Trinity College, Dublin 2, Ireland.|except possibly bad|
| Tel : +353-1-6772941 ext 1720 Fax : +353-1-6772204 |news"-Douglas Adams|
------------------------------
Date: Thu, 25 Feb 1993 14:12:21 GMT
From: "Allen W. Sherzer" <aws@iti.org>
Subject: Nobody cares about Fred?
Newsgroups: sci.space
In article <1993Feb23.174743.11705@aio.jsc.nasa.gov> munoz@sweetpea.jsc.nasa.gov (tomas o munoz 283-4072) writes:
>|> This sort of thruster is used by every satellite in existance. They are
>|> extremely reliable and shouldn't need servicing this often.
>Agreed. I assume you mean unmanned satellites, not man-rated vehicles.
Well the Apollo LM used them and it was man-rated. We can also service
them automatically so there is no problem.
>|> Well then maybe they can be refueled with expendables. That will save
>|> even more money.
>The problem I have with this suggestion is that you're talking about
>adding another system, starting up a new program.
Most of the systems we need exist today. Other near term systems can
reduce cost even more later.
>Although an ELV could
>probably do it cheaper, you still need the Shuttle. Therefore,
>you have the cost for two separate launch systems.
I disagree. We can use Atlas/Soyuz for crew transfer and expendables to handle
logistics. With Zenith Star HLV's we can do it for less than Shuttle
AND produce a more reliable logistics system since we will have backup
for any launcher which becomes unavailable.
>ELVs present several other logistics nightmares. Although you could build
>them to deliver whatever you want, how do you get stuff down.
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 to return that way.
Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves |
| aws@iti.org | nothing undone" |
+----------------------110 DAYS TO FIRST FLIGHT OF DCX----------------------+
------------------------------
Date: Thu, 25 Feb 1993 03:30:25 GMT
From: Frank Crary <fcrary@ucsu.Colorado.EDU>
Subject: Spaceflight for under $1,000?
Newsgroups: sci.space
In article <C2z6I1.8uw@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>Remember that good technical people cost you circa $1000/person/week even
>if you don't pay them terribly well.
I take it graduate students are only worth about one quarter of a
"good technical person"?
Frank Crary
CU Boulder
------------------------------
Date: 25 Feb 93 06:03:30 GMT
From: nsmca@acad3.alaska.edu
Subject: Spaceflight for under $1,000?
Newsgroups: sci.space
In article <C2z6I1.8uw@zoo.toronto.edu>, henry@zoo.toronto.edu (Henry Spencer) writes:
> In article <C2yFq8.G0p@cck.coventry.ac.uk> djf@cck.coventry.ac.uk (Marvin Batty) writes:
>>If, therefore, a company got together for the sole purpose of building
>>and launching one rocket, presumably the costs would be considerably smaller.
>>But does anyone have an idea what would be the minimum cost of putting one
>>man in orbit? Presumably the main costs are launchpad, fuel, lifesupport
>>and rocket.
>
> If you're fairly optimistic, you might assume launch costs as low as $500/kg.
> That's still awfully expensive. Reductions far beyond that are possible
> in principle, but there is no proof that they can be achieved in practice.
> There are some fairly major technical challenges involved in achieving
> those potential cost reductions. It's not something you're likely to
> manage in your basement.
>
> Remember that good technical people cost you circa $1000/person/week even
> if you don't pay them terribly well.
>
Hire some destitute homeless Russian Space Scientists and have them stay at
your house (your spose might not be excited about this)..
They would have to already be in the US or pay their own ways..
>>I heard somewhere that the latest Space Shuttle has five computers
>>which combined have less memory than a good PC. Is this really true?
>
> Yes, but those computers and that memory will survive conditions which
> would turn your PC into a paperweight. When you can't get home without
> them, you're a bit fussier about computer quality than the MSDOS crowd
> usually is.
Go MAC, it might last longer than a MSDOS machine..
> --
> C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology
> effect since OS/360. | henry@zoo.toronto.edu utzoo!henry
Maybe design a larger Goddard style liquid feul rocket..
------------------------------
Date: Thu, 25 Feb 1993 10:29:18 GMT
From: "Herity D." <dherity@cs.tcd.ie>
Subject: Spaceflight for under $1,000?
Newsgroups: sci.space
>A very minimalist launch of a few hundred kilos (i.e. sending a
>man onto orbit one way) would probably cost on the order of 50 million.
An Austrian bought a ticket to MIR for $12.5M, according to a BBC TV
documentary last week (Arena).
--
-----------------------------------------------------------|"Nothing travels |
| Dominic Herity, dherity@cs.tcd.ie, |faster than light, |
|Computer Science Dept, Trinity College, Dublin 2, Ireland.|except possibly bad|
| Tel : +353-1-6772941 ext 1720 Fax : +353-1-6772204 |news"-Douglas Adams|
------------------------------
Date: Thu, 25 Feb 93 10:58:53 GMT
From: Dean Adams <dnadams@nyx.cs.du.edu>
Subject: Spy Sats (Was: Are Landsat Satellites receivable?)
Newsgroups: sci.space
pands@pands.demon.co.uk (Paul Wilson) writes:
>I understood that the KH-12 was the major enhancement of the
>KH-11 in terms of visible-light imaging
"KH-12" and "Advanced KH-11" have both been used to describe
the same KH-11 follow-on system. I've seen the latter label
from more authoritative sources however...
>Lacrosse uses side-scan radar, and is a very different beast indeed.
Considerably different, but "side-scan" is how the airborne radar
imaging platforms operate. Lacrosse birds use an advanced Hughes
Synthetic Aperture Radar, which is pointed (down) at the target.
>BTW, only a single KH-12 is in orbit at any one time
That is not entirely correct. A better phrasing would be
a minimum of one Advanced KH-11 is always in orbit.
>(remember the fuss when both the Titan and the Shuttle were grounded
>at the same time,
Certainly...
>and the US didn't have launch capacity to replace
>the KH-12 which was running low on manoeuvering fuel?).
No, that situation was long before the first Advanced KH-11 series
satellite was launched. The single Keyhole in operation during that
period was KH11-6, launched in December 1984. KH11-5 was deorbited
just prior to the failed launch of KH11-7 in August 1985. This was
followed by a failed attempt in 1986 to launch the last KH-9 satellite
as a backup (KH9-20). The "crisis" was ended when KH11-8 and KH11-9
were launched in 1987 and 1988, respectively.
Then came two Advanced KH-11 birds deployed on Shuttle missions in 1989
and 1990. STS-28 carried the first of this new series, on the second
mission after the return to flight. During the Gulf war there were as
many as four Keyhole birds operating...
-{ Dean Adams }-
------------------------------
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From: Frank Crary <fcrary@ucsu.Colorado.EDU>
Subject: Re: Spaceflight for under $1,000?
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In article <C2yFq8.G0p@cck.coventry.ac.uk> djf@cck.coventry.ac.uk (Marvin Batty) writes:
>If, therefore, a company got together for the sole purpose of building
>and launching one rocket, presumably the costs would be considerably smaller.
>But does anyone have an idea what would be the minimum cost of putting one
>man in orbit?
Would you insist on returning him to Earth?
>...Presumably the main costs are launchpad, fuel, lifesupport
>and rocket.
A very minimalist launch of a few hundred kilos (i.e. sending a
man onto orbit one way) would probably cost on the order of 50 million.
>...I heard somewhere that the latest Space Shuttle has five
>computers which combined have less memory than a good PC. Is this really true?
Yes. Given NASA's safety and testing requirements, it takes years
for hardware to qualify. The computers on the Shuttle were very modern
when they were designed (over a decade ago...)
>Is it really possible for a small organisation to launch a man into space, if
>that is all it intends doing? I know this has shades of "The Mouse That Roared"
I think it would be very easy for a company to make a one way launch
and then hitch a ride back to Earth with (say) the Russians. (Of
course, the US government wouldn't like it and might create legal
obsticles...) The total price (including a ride with the Russians)
would probably be under $100 million. Possibly under $50 million.
I haven't checked the rates for 30-second ads during the Superbowl,
but I think a $50 million publicity stunt might not be unrealistis
for a major company.
Frank Crary
CU Boulder
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End of Space Digest Volume 16 : Issue 232
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