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Date: Fri, 22 Jan 93 05:00:03
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V16 #070
To: Space Digest Readers
Precedence: bulk
Space Digest Fri, 22 Jan 93 Volume 16 : Issue 070
Today's Topics:
2001/2010 Rocket Engines
2001/2010 Rocket Engines - What are they? (4 msgs)
Aurora
Bio-sphere II
Biosphere 2
DC-1 and the $23M NASA Toilet
Hewlett Packard conin space
JPL Anonymous FTP Site
Lunar Rotation
Lunar Rotation (was: Earth's rotation rate...)
Mars Observer Update - 01/20/93 (2 msgs)
Orbital elements of junk in space wanted
Question:How Long Until Privately Funded Space Colonization
Saving an overweight SSTO....
Toutatis Captured by Radar Images
Znamya
Znamya: Orbiting mirror.
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, 22 Jan 93 00:05:11 EST
From: John Roberts <roberts@cmr.ncsl.nist.gov>
Subject: 2001/2010 Rocket Engines
-From: mrw9e@kelvin.seas.Virginia.EDU (Michael Robert Williams)
-Subject: Re: 2001/2010 Rocket Engines - What are they?
-Date: 21 Jan 93 18:02:38 GMT
-Organization: University of Virginia
-I don't know about the "Leonov", but I remember reading something about
-Clarke's intentions for the Discovery's engines. He wanted to use a pulsed
-nuclear drive (something like Orion, I think) and tried to convince
-Stanley Kubrick to show the Discovery's engines pulsing on and off as
-the drive fired. It's been a while since I saw the film, but I don't
-remember seeing anything like that.
As I recall, they don't show the Discovery's engines firing until "2010".
I don't think Kubrick was involved in that movie.
John Roberts
roberts@cmr.ncsl.nist.gov
------------------------------
Date: Thu, 21 Jan 1993 12:02:47 GMT
From: Marcus Lindroos INF <MLINDROOS@FINABO.ABO.FI>
Subject: 2001/2010 Rocket Engines - What are they?
Newsgroups: sci.space
Any idea what kind of engines the "Discovery" and "Alexei Leonov" of "2010 -
Odyssey Two" were using? Obviously, they have to be pretty fuel-efficient [=an
exhaust velocity of at least 25km/s] since neither craft seems to have much
room for fuel aboard. Ion engines seem to be out of the question but what about
a fusion-powered plasma motor? The visual appearance of the nozzles [=not
bell-shaped like those of the Space Shuttle or a nuclear engine] plus the
fact that both vessels have clusters of small engines rather than three or
four big ones all suggest that the exhaust jets produced by the engines
contain little mass, but are being ejected at high velocities.
---
Does anyone know what the theoretical maximum exhaust velocity for an
"economical" fusion/plasma engine is, using standard propellants like methane,
water or hydrogen?
>
> MARCU$
>
> --------------------------------------------------------------------------
> . . . Fififinlandssvensk
>
> Marcus Lindroos Internet: mlindroos@abo.fi
> Computer Science
> Abo Akademi University
> Finland
------------------------------
Date: 21 Jan 93 15:07:39 GMT
From: Ed McCreary <edm@gocart.eng.hou.compaq.com>
Subject: 2001/2010 Rocket Engines - What are they?
Newsgroups: sci.space
>>>>> On Thu, 21 Jan 1993 12:02:47 GMT, MLINDROOS@FINABO.ABO.FI (Marcus Lindroos INF) said:
MLI> Any idea what kind of engines the "Discovery" and "Alexei Leonov" of "2010 -
MLI> Odyssey Two" were using? Obviously, they have to be pretty fuel-efficient [=an
MLI> exhaust velocity of at least 25km/s] since neither craft seems to have much
Hmm, It's been a while since I read 2001, although I saw the movie
this weekend, so I don't remember if they went into any details. I do
know that 2010 does have a blurb on the Leonov's engines. You may
want to grab a paperback and check it out. My failing memory tells
me it used some sort of "low" temp muon catalyzed fusion. I think
Luis Alvarez was supposed to have done the theoretical work for it.
(In the book, that is, although Clarke derived some details from
Alvarez's actual work)
--
Ed McCreary ,__o
edm@gocart.eng.hou.compaq.com _-\_<,
"If it were not for laughter, there would be no Tao." (*)/'(*)
------------------------------
Date: 21 Jan 93 17:04:38 GMT
From: Bill Higgins-- Beam Jockey <higgins@fnalf.fnal.gov>
Subject: 2001/2010 Rocket Engines - What are they?
Newsgroups: sci.space
In article <1993Jan21.120247.11867@abo.fi>, MLINDROOS@FINABO.ABO.FI (Marcus Lindroos INF) writes:
> Any idea what kind of engines the "Discovery" and "Alexei Leonov" of "2010 -
> Odyssey Two" were using?
Yup. For the *Discovery* they are gaseous-core fission engines-- in
other words, a fission reactor running at a *really* high temperature,
20,000 degrees F (11,000 C). (If I were a journalist, I probably
would have written 11093.33 degrees C...) Liquid hydrogen flows past
this to serve as exhaust fluid and to help keep the graphite walls
cooled. Consult a book on advanced space propulsion for details.
Source: Frederick I. Ordway, III, "*2001: A Space Odyssey* in
Retrospect," p. 47-105 in the book *Science Fiction and Space Futures*
by Eugene M. Emme (AAS History Series, Volume 5), Univelt. Fred was a
technical advisor on the film and this article is a great source of
behind-the-scenes information and pictures (fifty pages' worth!).
I don't know of anyplace where the propulsion of the *Leonov* is
discussed, but it's reasonable to suppose they use gas-core engines
too.
I always thought this technology was a trifle advanced to be ready in
only 2001, but remember that Kubrick's people were busy little beavers
in the 34 years following 1967-- they had dug out underground hangars
on the Moon for their spacecraft, with elevators, had started regular
Pan Am service to orbit, had built half a space station (but Clarke
pointed out in the Fifties in *Islands in the Sky* that you would
finish building the wheel FIRST, and THEN spin it up!), and by 12
January 1992 had achieved artificial intelligence.
It is sad to think that *they* were supposed to be *us*. :-(
--
O~~* /_) ' / / /_/ ' , , ' ,_ _ \|/
- ~ -~~~~~~~~~~~/_) / / / / / / (_) (_) / / / _\~~~~~~~~~~~zap!
/ \ (_) (_) / | \
| | Bill Higgins Fermi National Accelerator Laboratory
\ / Bitnet: HIGGINS@FNAL.BITNET
- - Internet: HIGGINS@FNAL.FNAL.GOV
~ SPAN/Hepnet: 43011::HIGGINS
------------------------------
Date: Thu, 21 Jan 1993 18:02:38 GMT
From: Michael Robert Williams <mrw9e@kelvin.seas.Virginia.EDU>
Subject: 2001/2010 Rocket Engines - What are they?
Newsgroups: sci.space
I don't know about the "Leonov", but I remember reading something about
Clarke's intentions for the Discovery's engines. He wanted to use a pulsed
nuclear drive (something like Orion, I think) and tried to convince
Stanley Kubrick to show the Discovery's engines pulsing on and off as
the drive fired. It's been a while since I saw the film, but I don't
remember seeing anything like that.
In Real Life:Mike Williams | Perpetual Grad Student
e-mail :mrw9e@virginia.edu| - It's not just a job, it's an indenture
---------------------------------------------------------------------------
"If you ever have a world of your own, plan ahead- don't eat it." ST:TNG
------------------------------
Date: Thu, 21 Jan 93 16:31:51 MET
From: PHARABOD@FRCPN11.IN2P3.FR
Subject: Aurora
From "International Herald Tribune", January 21, 1993:
U.S. SUPERPLANE: ANOTHER UFO TALE ?
by Malcolm W. Browne, New York Times Service
NEW YORK - Rumors and reported sightings of a secret American superplane
have been spreading lately almost as abundantly as yarns about
unidentified flying objects.
But despite the acknowledged yearning of many American aviation
experts and buffs for an ultra-fast spy plane, it appears that
development of even the engine needed for such a plane is moving faster
in Russia than in the United States.
Advancing the case for wishful thinking, John E. Pike, an aviation
expert, has written: "Belief in the existence of marvelously capable
and highly secret aircraft resonates with some of the deeper anxieties
of contemporary American society. Aviation has long been one of the
distinguishing attributes of American greatness, but the declining
fortunes of the American aerospace industry have created growing
uncertainties about the future."
The possible existence of a new American intelligence-gathering
plane capable of flying at eight times the speed of sound has been
suggested in recent articles in the British periodical Jane's Defense
Weekly, the American magazine Aviation Week & Space Technology and
other respected technical publications.
These reports are based partly on sightings of large and unusually
shaped airplanes, peculiar looking condensation trails left by high-
flying aircraft, and strange rumbling sounds around the world.
Some experts say they believe the purported sightings of a hypersonic
reconnaissance plane are credible in light of some mysterious Defense
Departement budget items in the 1980s referring to a project called
"Aurora".
Donald B. Rice, secretary of the air force, said last month that
reports of such an aircraft were "fantasy."
William Sweetman, author of the report published in December by
Jane's Defense Weekly, still believes in the existence of some kind
of secret, high-speed spy plane.
"Many of these sightings were from highly qualified and credible
observers," he said.
Meanwhile, Russia and its French aerospace partners have announced
the successful test firing of a "scramjet" engine - an engine that
operates at speeds starting at five times that of sound, and capable
of boosting an airplane toward orbit outside the atmosphere.
The French-Russian test, as reported by Aviation Week & Space
Technology, was carried out Nov. 17 in Kazakhstan.
(end of article)
------------------------------
Date: 21 Jan 93 13:18:03 GMT
From: Paul Dietz <dietz@cs.rochester.edu>
Subject: Bio-sphere II
Newsgroups: sci.space
From: Carl Hage <hage@netcom.com>
> .... Also, it would seem that odor might be a problem
> in such a small enclosed space.
I understand that they have a system where air is recirculated through
a large mass of soil. This replicates one of the mechanisms of the
natural biosphere for cleansing the atmosphere. Microorganisms are
significant sinks for CO, H2, and numerous other trace gases. And,
indeed, they claim that odors have not been a problem.
I have read, however, that the Shuttle is pretty rank at the end of a
flight. Is this true?
Paul F. Dietz
dietz@cs.rochester.edu
------------------------------
Date: Thu, 21 Jan 93 23:57:53 EST
From: John Roberts <roberts@cmr.ncsl.nist.gov>
Subject: Biosphere 2
-From: dietz@cs.rochester.edu (Paul Dietz)
-Subject: Re: Bio-sphere II
-Date: 21 Jan 93 13:18:03 GMT
-Organization: University of Rochester
-I have read, however, that the Shuttle is pretty rank at the end of a
-flight. Is this true?
During one of the STS-54 press conferences (near the end of the mission)
it was mentioned that there was an odor from the "wet trash" (banana peels,
food wrappers, etc.), but not from the new WCS. Apparently the trash bin
is supposed to be ventilated by a vacuum line (not sure whether there's a
pump involved, or whether they just run a pipe to the outside), and they
determined that there was a vacuum on the line, so they weren't quite sure
what the problem was.
I think the air from the WCS is run through a chemical filter and fed back
into the cabin.
Since they made a point of remarking on it, I'd guess there usually isn't
too much of a problem with odor.
John Roberts
roberts@cmr.ncsl.nist.gov
------------------------------
Date: 21 Jan 93 18:46:21 GMT
From: Pat <prb@access.digex.com>
Subject: DC-1 and the $23M NASA Toilet
Newsgroups: sci.space
>bern@Uni-Trier.DE (Jochen Bern) writes:
>
>>The REALLY funny Thing about it is that the 2001
>>Starship had artificial Gravity in at least a Part of the Ship; Every
>>Idiot would have chosen to put into that Area.
>
Of course, you have to consider one thing. There will be times when the
spinner section has to started or stopped due to maintenance.
wouldn't taht suck if you had to go during a maintenance cycle?
------------------------------
Date: 21 Jan 93 18:41:38 GMT
From: kjenks@gothamcity.jsc.nasa.gov
Subject: Hewlett Packard conin space
Newsgroups: sci.astro,sci.space
In article <1jdru6INNijp@hpscit.sc.hp.com> stevep@hpscit.sc.hp.com () writes:
>There was the HP handheld calculator that was used on some (I think)
>Apollo missions.
In the early days of the Space Shuttle Program, we used an HP
calculator for some on-board calculations. I believe it had programs
to figure CG and even deorbit burns if the Primary Avionics Software
System (PASS) computers were down and if the Orbiter were out of
communication with the Mission Control Center (MCC). The functions of
the HP were subsumed by the Shuttle Payload On-board Computer (SPOC), a
GRiD '386 computer, which was later replaced with the Payload and
General Support Computer (PGSC), a GRiD 1530 '386 computer running the
SPOC software.
Before you ask, the SPOC software is NOT available to the general
public. It includes a world map showing day/night and the current
position of the Orbiter, updated in real time. You can see a SPOC (or
a PGSC running SPOC software) in quite a few photos from the flight
deck.
(That's from memory; I don't have time to dig up references right now.)
-- Ken Jenks, NASA/JSC/GM2, Space Shuttle Program Office
kjenks@gothamcity.jsc.nasa.gov (713) 483-4368
"It is mankind's manifest destiny to bring our humanity into space,
to colonize this galaxy. And as a nation, we have the power to
determine whether America will lead or will follow.
I say that America must lead." -- Ronald Reagan
------------------------------
Date: 21 Jan 93 18:55:34 GMT
From: Lan Pham <lpham@eis.calstate.edu>
Subject: JPL Anonymous FTP Site
Newsgroups: sci.space
Hello every body.
A few weeks ago I saw an article in this newsgroup regarding an anonymous ftp
site of nasa.gov where we can get gif files of latest images.
Unfortunately, I did not save that article. If any one has a record of it,
please repost or send it directly to me to save the bandwidth. I really
appreciate.
Thank you very much.
lanpham
baalke@kelvin.Jpl.Nasa.Gov (Ron Baalke) writes:
> Forwarded from:
> PUBLIC INFORMATION OFFICE
> JET PROPULSION LABORATORY
> CALIFORNIA INSTITUTE OF TECHNOLOGY
> NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
> PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
>
> JPL Pubinfo
> January 20, 1993
>
> A public access computer site containing information on and
> images from missions conducted by NASA's Jet Propulsion
> Laboratory has been opened by the JPL Public Information
> Office.
>
> The site may be reached by modem over phone lines, or by file
> transfer protocol (ftp) over Internet.
>
> Contents of the site include:
>
> -- JPL news releases, status reports, fact sheets and
> other data on JPL missions.
>
> -- Images from JPL missions as GIF computer files.
> These may be displayed on various makes of computers;
> viewing software may also be downloaded.
>
> -- Back issues of JPL's in-house newspaper, Universe.
>
> In addition, teacher materials provided by the JPL Public
> Education Office are planned to be added shortly.
>
> Public users of the site currently may connect to it by the
> following methods:
>
> -- By modem over commercial telephone lines to
> +1 (818) 354-1333. Set parameters to no parity, 8 data
> bits, 1 stop bit. This line supports speeds up to 9600
> bps with the v32/v42bis/MNP5 error correction and
> compression protocols, and supports up to two callers
> simultaneously.
>
> -- Users with Internet access can use anonymous ftp to
> pubinfo.jpl.nasa.gov (128.149.6.2). Log on as user
> ANONYMOUS, then send your city and state (city and
> country if other than USA) as the password (commas
> and spaces are ok, up to a total of 15 characters).
>
> For more information on this site, please call
> (818) 354-7170.
>
> [Note to Internet users: Although this site is not intended
> to support interactive communication, your comments or
> questions are welcome via email to newsdesk@jplpost.jpl.nasa.gov.]
>
> #####
> ___ _____ ___
> /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
> | | | | __ \ /| | | | Jet Propulsion Lab |
> ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Every once in a while,
> /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | try pushing your luck.
> |_____|/ |_|/ |_____|/ |
>
------------------------------
Date: Fri, 22 Jan 93 00:22:50 EST
From: John Roberts <roberts@cmr.ncsl.nist.gov>
Subject: Lunar Rotation
-From: lwall@netlabs.com (Larry Wall)
-Subject: Re: Lunar Rotation (was: Earth's rotation rate...)
-Date: 21 Jan 93 20:15:20 GMT
-Organization: NetLabs, Inc.
-In article <C16EL7.Cqw@brunel.ac.uk> mt90dac@brunel.ac.uk (Del Cotter) writes:
-: BTW, I heard that the Moon is actually *bistable*. Aren't we lucky we
-: got the pretty face?
-If we get bored we could always turn the Moon the other way 'round...
The center of mass of the moon is displaced from the geometric center by
2-3 km. That being the case, it seems unlikely that it's bistable.
Incidentally, this displacement provides evidence that the moon's tidal lock
was achieved while it was still molten. (It's thought that the chief feature
of the asymmetry is a much thicker crust on the far side. This would also
account for the greater incidence of mascons on the near side.)
John Roberts
roberts@cmr.ncsl.nist.gov
------------------------------
Date: 21 Jan 93 20:15:20 GMT
From: Larry Wall <lwall@netlabs.com>
Subject: Lunar Rotation (was: Earth's rotation rate...)
Newsgroups: sci.space
In article <C16EL7.Cqw@brunel.ac.uk> mt90dac@brunel.ac.uk (Del Cotter) writes:
: BTW, I heard that the Moon is actually *bistable*. Aren't we lucky we
: got the pretty face?
If we get bored we could always turn the Moon the other way 'round...
Larry Wall
lwall@netlabs.com
------------------------------
Date: 21 Jan 93 17:23:27 GMT
From: Ron Baalke <baalke@kelvin.jpl.nasa.gov>
Subject: Mars Observer Update - 01/20/93
Newsgroups: sci.space,sci.astro,alt.sci.planetary
Forwarded from the Mars Observer Project
MARS OBSERVER STATUS REPORT
January 20, 1993
9:00 AM PST
Flight Sequence C6 B became active at 11:58 AM on January 18.
Magnetometer/Electron Reflectometer, Gamma Ray Spectrometer, and
Mars Observer Camera were powered on for instrument calibration
activities. The MOC test continues through noon Monday, January 25, while
MAG/ER (Magnetometer/Electron Reflectometer) and GRS (Gamma Ray Spectrometer)
calibrations continue beyond that date. The MOC PI (Principal Investigator)
reports that the instrument is performing as expected, but will not have
image information available until sufficient analysis has been performed.
Digital Tape Recorders 1 and 3 will be played back on January 26 and 27.
DTRs 1 and 3 contain the Geotail measurement data collected in December.
Efforts to receive Ka band telemetry last week were successful.
The Spacecraft Team reports that the spacecraft is performing nominally
in Array Normal Spin. Uplink and downlink are via the HGA (High Gain
Antenna); uplink is at 125 bps; downlink at the 2k engineering rate during
periods of minimal activity, the 4k Science and Engineering rate during
instrument calibration activities, and at 16K during DTR playback.
Today the spacecraft is 58,313,994 km (36,234,636 miles) from Earth,
traveling at a velocity of 12.9012 kilometers per second (28,859 miles
per hour) with respect to Earth. One way light time is approximately 195
seconds.
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Every once in a while,
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | try pushing your luck.
|_____|/ |_|/ |_____|/ |
------------------------------
Date: 21 Jan 93 19:31:27 GMT
From: "Thomas E. Smith" <motif!tes>
Subject: Mars Observer Update - 01/20/93
Newsgroups: sci.space
Ron Baalke writes:
>Today the spacecraft is 58,313,994 km (36,234,636 miles) from Earth,
>traveling at a velocity of 12.9012 kilometers per second (28,859 miles
>per hour) with respect to Earth. One way light time is approximately 195
>seconds.
I wrote down this info on 12-30-92, and the velocity was 9.4083km/s. Is the
acceleration due to Mars's gravitational pull, or from the Earth dropping
away from the probe because of the Earth's circular orbit?
--
____________________________________________________________________________
| It's not my damn planet, understand | Tom E. Smith |
| Monkey Boy?!! John Bigbootey | tes@gothamcity.jsc.nasa.gov |
----------------------------------------------------------------------------
------------------------------
Date: Thu, 21 Jan 93 17:21:54 MET
From: PHARABOD@FRCPN11.IN2P3.FR
Subject: Orbital elements of junk in space wanted
> Yep, NORAD does keep a listing of "everything" seeing how all data
> pathways lead to NORAD. And that guy that you call up to find out if
> your object such-and-such is a piece of debris, a classified sat, or
> something unknown that is not in the catalog is probably me or someone
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> in my office. We do this alot for our observation guys and they HAVE
> found pieces that NORAD did not know about or had reported lost.
^^^^^^^^^^^^^^^^^^
> David Fuzzy Wells (Tue, 19 Jan 93 05:16:21 GMT)
Russia (ex-USSR) ?
Other known launching nation(s) (China, Japan, France, etc...) ?
Unknown launching nation(s) ?
Meteorites ?
Little natural satellites ?
High altitude physical phenomena ?
Very high-flying secret aircraft ?
Other ?
Within the computer software analysing these events, is there some
kind of filter eliminating the objects (if any) which disappear soon
after being detected, or which don't obey strictly the laws of
gravitation and/or atmospheric re-entry ?
J. Pharabod
------------------------------
Date: 18 Jan 93 23:28:11 MDT
From: Andrew Folkins <cuenews!andrew>
Subject: Question:How Long Until Privately Funded Space Colonization
Newsgroups: sci.space
In <1993Jan7.211905.21553@iti.org> aws@iti.org (Allen W. Sherzer) writes:
>I think they where kind of drifting in the past but the unfortunate
>death of Gerald Oneil seems to have galvanized them.
What? When did that happen? Damn...
--
Andrew Folkins andrew@ve6mgs.ampr.ab.ca
...!cs.ualberta.ca!adec23!ve6mgs!cuenews!andrew
------------------------------
Date: 19 Jan 93 16:42:21 GMT
From: Dani Eder <eder@hsvaic.boeing.com>
Subject: Saving an overweight SSTO....
Newsgroups: sci.space
Bruce_Dunn@mindlink.bc.ca (Bruce Dunn) writes:
>> Dani Eder writes:
>> If you are trying to deliver cargo (not necessarily people) at the lowest
>> cost per kg, then the solution is to fly the DC-1 sub-orbital (to about
>> 0.7 of orbital velocity) and kick out the payload with a solid kick
>> motor attached. The numbers go like this:
> Interesting idea. Without a full orbital flight, the DC-1 will not
>be able to land at its launch site. Any idea on how far downrange the DC-1
>would land, and whether this could be accomplished within the width of the
>continental USA? If not, or a Florida launch is needed to get a 28.5 degree
>orbit, where in Africa would be a suitable landing site? A quick look at a
>globe suggests launching from Hawaii would require landing somewhere the the
>northern half of south America. Return to the launch site would presumably be
>by another suborbital hop, although this unfortunately means that two
>refueling and launch sites are needed and two DC-1 flights are needed to put
>1 payload into orbit.
> Drawings of the current concept for the DC-1 show a mid-body cargo
>bay 15x15x30 feet with a door to the side of the spacecraft. Once out of the
>atmosphere and finished the boost phase, the door will have to be opened and
>the payload ejected and the door shut again before the DC-1 reenters. This
>has to work flawlessly in a very constrained time period - reentering with
>the payload bay door still open would probably be disasterous. Any estimate
>of the time available between the end of boost and the beginning of reentry?
According to one source I have (Design Data for Astronautics and
Aeronautics, R. B. Morrison, ed, John Wiley&Sons, 1962), for
a cutoff velocity of 18,000 ft/s, altitude of 100 miles, and path
angle of 5 degrees above horizontal, the range to landing from
cutoff is about 1500 miles. Assuming 3 g acceleration to get to
speed, the acceleration distance will be 300 miles, so the total
range is 1800 miles. The payload launch hop would be near horizontal
so as to leave the solid motor lined up for a LEO insertion.
On the return hop, you would go for maximum range with minimum
velocity. This would have a cutoff path angle of about 37.5
degrees above horizontal, and requires a velocity of about
16,000 ft/s (0.62 orbit velocity). The peak height reached on
the return trip would be 2,200 miles.
This method of return is sometimes referred to as 'blast-back', as
contrasted to 'flyback' discussed for some boosters.
Time of flight from cutoff to re-entry would be about 5 minutes. Note
that commercial aircraft landing gear doors operate flawlessly
better than 99,999 out of 100,000 (there would be lots of crashes
that we would hear about otherwise). So I would get guys who
do landing gear doors to do the design.
Baja California at 28.5 Latitude to the Kennedy Space Center works
out to be the right distance. Note that while you are making two
flights, the engines will be running only 1.3 times the SSTO run
time, and the total heat load for the re-entry system is 0.87 times
the SSTO heat load, and it is divided into two re-entries, so the
heat shield could be lighter weight, since it dissipates less heat
each re-entry. So, on net, I would guess that the maintenance
load for two sub-orbital hops would be about the same as for
one full SSTO flight. Note also that the sub-orbital trips
are very short (about 20 minutes), so your electrical power
supply would be smaller than for an orbital mission (1.5 hours
or more).
Dani Eder
--
Dani Eder/Meridian Investment Company/(205)464-2697(w)/232-7467(h)/
Rt.1, Box 188-2, Athens AL 35611/Location: 34deg 37' N 86deg 43' W +100m alt.
------------------------------
Date: Thu, 21 Jan 1993 13:40:39 CET
From: K3032E0@ALIJKU11.BITNET
Subject: Toutatis Captured by Radar Images
Newsgroups: sci.space,sci.astro,alt.sci.planetary
Has anyone an idea to which class "Toutatis" belongs? Is it a S-type-
asteroid like "Gaspra"? Are the two bodies which form "TWOtatis" of the
same spectral type?
As earth-crossers are probable parent-bodies for meteorites, it would be
interesting to know which type of meteorite may come from "Toutatis" (or
similar objects).
Herbert
------------------------------
Date: Thu, 21 Jan 1993 16:34:51 -0600
From: pgf@srl02.cacs.usl.edu (Phil G. Fraering)
Subject: Znamya
\I hope everybody here recognized the obsurdity of thinking that a 20
/meter mirror could "extend the daylight hours of the Siberian regions."
\'The Guardian' clearly doesn't. (Typical newspaper science writing.)
/The most the mirror would do is make a bright spot in the sky.
Or test the deployment mechanism for a larger mirror more useful
for illumination.
\But, as my .sig notes, journalists don't have a monopoly on stupidity.
/-- Ken Jenks, NASA/JSC/GM2, Space Shuttle Program Office
\ kjenks@gothamcity.jsc.nasa.gov (713) 483-4368
Later... maybe even next semester... this account's probably going away...
--
Phil Fraering |"...Who in the valley shed the poison tear
318/365-5418 |no one knows...
pgf@srl02.cacs.usl.edu|An old legend of a mythical hero..."
------------------------------
Date: Thu, 21 Jan 1993 18:49:04 GMT
From: "Kenneth C. Jenks [GM2] (713" <gothamcity!kjenks>
Subject: Znamya: Orbiting mirror.
Newsgroups: sci.space
In article <30262@castle.ed.ac.uk>, ntc@castle.ed.ac.uk (N T Clifford) writes:
>
> A report carried in `The Guardian' (Thursday January 14) detailed an
> upcoming Russian space event.
>
> Apparently a recent Progress cargo ship (1992-71A?) currently docked
> (or station keeping) with Mir is due (maybe next month) to unfurl a 65
> foot 'space mirror' constructed from aluminium coated plastic film, in
> an experiment known as `Znamya' (Banner).
>
> Apparently this is an attempt to extend the daylight hours of the
> Siberian regions by reflecting sunlight to the required areas.
I hope everybody here recognized the obsurdity of thinking that a 20
meter mirror could "extend the daylight hours of the Siberian regions."
'The Guardian' clearly doesn't. (Typical newspaper science writing.)
The most the mirror would do is make a bright spot in the sky.
But, as my .sig notes, journalists don't have a monopoly on stupidity.
-- Ken Jenks, NASA/JSC/GM2, Space Shuttle Program Office
kjenks@gothamcity.jsc.nasa.gov (713) 483-4368
"Even considering the improvements possible... the gas
turbine [jet] could hardly be considered a feasible application
to airplanes because of the difficulty of complying with the
stringent weight requirements."
-- US National Academy of Sciences, 1940
"It may not be possible to build a vehicle with single-stage-
to-orbit capability in the mid 1990s."
-- US National Academy of Sciences, 1990
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End of Space Digest Volume 16 : Issue 070
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