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Space Digest Thu, 12 Aug 93 Volume 17 : Issue 016
Today's Topics:
A couple of space questionz.
DC-X (2 msgs)
DC-X press (UK)
Electronic Journal of the ASA (EJASA) - August 1993 * FOURTH YEAR! [Part 2]
funny space (2 msgs)
Henry Spencer in the Slow Zone (Re: Ghost Wheels & HenrySpancer_Zoo)
man-made meteor storm?
Mars Observer's First Photo
Mars Observer GIF Image (3 msgs)
Orbital Information (2 msgs)
Simple Space Plane!
Stage 1 to Mars!
Why the Shuttle will never be popular.
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: Wed, 11 Aug 1993 16:27:58 GMT
From: Quagga <quagga@trystero.com>
Subject: A couple of space questionz.
Newsgroups: sci.space
1) Does the term 'Periapsis' refer to a Venus orbit?
2) Anybody remember the guy... Um...lesee.. I think he was a University
professor, very interested in trajectories...worked with NASA on things
like planning the 'grand tour' planetary satellite mission? I think
this person also managed to come up with a clever way to get the
(Solar Max?) satellite to beat some other satellites to rendezvous with
Halleys Comet a few years ago..
I'll bet he has some interesting stories.
\o/-<AWOO!> equus quagga
(( quagga@trystero.com
\\ "But you can call me Cheryl.."
------------------------------
Date: Wed, 11 Aug 1993 18:48:39 GMT
From: fred j mccall 575-3539 <mccall@mksol.dseg.ti.com>
Subject: DC-X
Newsgroups: sci.space
In <Scott_Chisholm-110893111048@141.211.210.249> Scott_Chisholm@um.cc.umich.edu (Scott Chisholm) writes:
> Jeez! I make a little comment and the grammar police come out to play.
>Sorry, I don't have a spell checker in my communications program. BTW,
>wouldn't your time be better spent getting that shuttle thing back in space
>instead of correcting bad spelling? I THOUGHT this was how my money was
>being spent at NASA. It shows.
God, *another* Freshman.
--
"Insisting on perfect safety is for people who don't have the balls to live
in the real world." -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
Fred.McCall@dseg.ti.com - I don't speak for others and they don't speak for me.
------------------------------
Date: Wed, 11 Aug 1993 22:24:36 GMT
From: "Phil G. Fraering" <pgf@srl03.cacs.usl.edu>
Subject: DC-X
Newsgroups: sci.space
mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes:
>God, *another* Freshman.
There are more coming. Switch to decaf.
--
+-----------------------+
|"Standard disclaimer" |Clever quote will be back next week!
|pgf@srl03.cacs.usl.edu |
+-----------------------+
------------------------------
Date: 11 Aug 1993 22:22:28 +0100
From: Mike C Holderness <mch@doc.ic.ac.uk>
Subject: DC-X press (UK)
Newsgroups: sci.space
Readers with access to Profile should search for "Clipping the costs of
high fliers" by Peter Bond, Independent (London UK) Monday August 8 1993.
The headline gives the tone... it's supportive refers to the possibility of
launches for "less than $10M, and perhaps as low as $1M".
The Independent is a national daily with a circulation in the 300k range --
fourth of the four broadsheets in the UK but taken pretty seriously.
=mike=
------------------------------
Date: Wed, 11 Aug 1993 19:04:44 GMT
From: Larry Klaes <klaes@verga.enet.dec.com>
Subject: Electronic Journal of the ASA (EJASA) - August 1993 * FOURTH YEAR! [Part 2]
Newsgroups: sci.astro,sci.space,sci.misc,sci.geo.geology,sci.environment,talk.environment,talk.politics.space,alt.sci.planetary
marketing or otherwise promoting the sale or use of goods and
services." As Glenn Reynolds, Executive Vice President of the
National Space Society (NSS) and law professor at the University of
Tennessee, puts it: "This bill is a law professor's nightmare. If
one of my students had drafted this, I'd have given him an F, because
the definition of space advertising is so broad, it basically outlaws
everything - TV commercials, company logos on the sides of rockets,
the works. It's sloppy."
Obviously, any proposal that would add to the growing influence of
light pollution should rightly be fought. Astronomers have a tough
enough time as it is these days plying their trade through the current
flood of light pollution. Astronomy educators are finding it
increasingly difficult to teach the wonders of the heavens when fewer
and fewer stars are available to view. While this particular proposal
does not seem all that bad on the face of it, there will be proposals
submitted within the next five years that will directly affect the
night time light pollution.
I urge everyone to get ready to battle these future proposals if
you wish to continue seeing the stars at all. The best way is to let
our elected officials know how we feel on the subject. Contact the
elected representatives of your state, province, or country and let
them know that you refuse to allow the night sky to become a background
for commercial advertising. You can also leave a telephone message for
U.S. Vice President Al Gore at (202) 456-1111, from 9 a.m. to 5 p.m.
Eastern Time (ET). As the self-proclaimed "environmentally-friendly
Vice President", this is an excellent litmus test.
For further information on this particular proposal, or others
along the same vein, you may contact the author, Earl W. Phillips,
Jr., by U.S. Mail at 7893 Thornfield Lane, Columbus, Ohio 43235; or
by telephone from 6 p.m. to 10 p.m. Monday through Friday, and 10
a.m. to 10 p.m. on the weekends at (614) 764-0476.
Light/Space Pollution Education: Getting Started
If you are interested in stopping light and space pollution,
perhaps the first thing to do is join the International Dark-Sky
Association (IDA). They have a large collection of "information
sheets" that are packed with lots of detail, ideas, and data.
The IDA address is:
International Dark-Sky Association
Dave Crawford, Executive Director
3545 N. Stewart
Tucson, Arizona 85716
U.S.A.
Telephone: 602-325-9346
Fax: 602-325-9360
Internet Address: crawford@noao.edu or dcrawford@noao.edu
Related EJASA Articles -
"Stopping Space and Light Pollution", by Larry Klaes and Phil
Karn - September 1989
"When the Light Gets in Your Eyes, You Shouldn't Have to Drive
to the Country", by James Smith and Ken Poshedly - February 1991
"Curbing Light Pollution in Ohio", by Robert Bunge - June 1991
"Street Lights: The Real Cost", by Steve and Stephanie Binkley -
August 1991
"The Battle Against Light Pollution in Central Ohio", by Earl W.
Phillips, Jr. - September 1991
"Fade to White: The Loss of the Night Sky", by Robert Bunge -
May 1993
About the Author (by the author) -
I am an avid amateur astronomer as well as a part-time researcher
at Perkins Observatory in Delaware, Ohio. I am the RFI Director at
the "Big Ear" radio telescope at Ohio State University (OSU), where we
have been conducting SETI (Search for ExtraTerrestrial Intelligence)
research for more than two decades [You can read about Big Ear and
its SETI project in the June 1992 EJASA. - Editor]. I am an Astronomy
Teaching Assistant under Dr. Phillip Barnhart at Otterbein College
in Westerville, Ohio, and Chief Observer of Otterbein's Weitkamp
Observatory.
I am also the founder of an amateur astronomy club, the Westerville
Astronomy Interest Group (WAIG), whose members learn about the night
sky, contribute to educating the general public through the sponsorship
of public programs, and perform astrophotography and other classes for
its members.
I have conducted a campaign against light pollution to save the
skies surrounding Perkins Observatory for over the last two years.
This has resulted in the first light pollution regulations ever in
Central Ohio. They have either been written into existing zoning
codes or - currently under consideration - in four different local
governmental districts.
I am the current editor of SIGNALS, the newsletter of the "Big Ear"
radio telescope, which has a global circulation, as well as of THE
CASSIOPEAN, the newsletter of the WAIG. I have contributed articles
to the EJASA as well as various newsletters of the astronomical com-
munity on topics ranging from beginning astronomy to light pollution.
I can be reached by mail at: Earl W. Phillips, Jr., 7893
Thornfield Lane, Columbus, Ohio 43235; or by telephone at (614)
764-0476 from 6 p.m. to 10 p.m. weekdays and from 10 a.m. to 10 p.m.
on weekends; or electronically at ephillip@magnus.ircc.ohio-state.edu.
SIGNALS is the official newsletter of the Ohio State University's
(OSU) radio telescope named "Big Ear". Produced more or less monthly,
it describes the goings on at the radio telescope, current research
updates, and occasionally offers preprints. Big Ear is under the
directorship of Dr. Robert Dixon and has been doing SETI research for
over twenty years. For a one-year subscription, send twenty dollars
($20) to: NAAPO, SIGNALS Subscriptions, care of Otterbein College,
Department Physics/Astronomy, Westerville, Ohio 43081. Mention you
read it in the EJASA!
Earl is the author of the following EJASA articles:
"The Battle Against Light Pollution in Central Ohio" - September 1991
"A History of Ohio's Perkins Observatory" - February 1992
THE ELECTRONIC JOURNAL OF THE ASTRONOMICAL SOCIETY OF THE ATLANTIC
August 1993 - Vol. 5, No. 1
Copyright (c) 1993 - ASA
------------------------------
Date: Wed, 11 Aug 1993 18:30:14 GMT
From: "Simon E. Booth" <sbooth@lonestar.utsa.edu>
Subject: funny space
Newsgroups: sci.space
In article <9AUG199315393038@zeus.tamu.edu> craigk@zeus.tamu.edu (Windows NT: from the people who brought you EDLIN.) writes:
>
>
>>TV for Tuesday, 16 April 1999, 8 pm, Ch. 9 LET FREEDOM WRING (Comedy/Drama)
>>
>>Frustrated and bored by the lack of a clear scientific goal, the eight, or
>>possibly four, astronauts on Space Station Freedom set up a mock TV game show
>>and take turns trying to guess the cost of various on-board components. The
>>monotony is broken by an order from OSHA requiring that a wheel-chair ramp be
>>constructed on the docking port, or NASA may no longer accept Federal funds.
I like this idea, but would NASA allow me to use my off-the-shelf wheelchair
in space or would they require some ultra-exotic space-proven version? :-
(just my luck though the ramp w be too steep and I'd ly end up
flipping over and 'falliaway from the station, doing a Slim Pickens
imitation :-) )
too bad space is the only place where I could be on equal terms with everyone
else.....
oh well.
Simon
Into the long darkness- Alone in the unknown-|Simon E. Booth (Epsilon class)
I see nothing ahead of me- |email: sbooth@lonestar.utsa.edu
Smashed under the treads of fate-
The future is now only a distant memory. ('Transition: Into the Unknown',1993)
------------------------------
Date: Wed, 11 Aug 1993 20:55:54 GMT
From: "Simon E. Booth" <sbooth@lonestar.utsa.edu>
Subject: funny space
Newsgroups: sci.space
In article <9AUG199315393038@zeus.tamu.edu> craigk@zeus.tamu.edu (Windows NT: from the people who brought you EDLIN.) writes:
>
>
>TV for Tuesday, 16 April 1999, 8 pm, Ch. 9 LET FREEDOM WRING (Comedy/Drama)
>
>Frustrated and bored by the lack of a clear scientific goal, the eight, or
>possibly four, astronauts on Space Station Freedom set up a mock TV game show
>and take turns trying to guess the cost of various on-board components. The
>monotony is broken by an order from OSHA requiring that a wheel-chair ramp be
>constructed on the docking port, or NASA may no longer accept Federal funds.
I like this idea, but would NASA allow me to use my off-the-shelf wheelchair
in space or would they require some ultra-exotic space-proven version? :-)
(just my luck though the ramp would be too steep and I'd end up
flipping over and 'falling' away from the station, doing a Slim Pickens
imitation :-) )
too bad space is the only place where I could be on equal terms with everyone
else.....
oh well.
Simon
Into the long darkness- Alone in the unknown-|Simon E. Booth (Epsilon class)
I see nothing ahead of me- |email: sbooth@lonestar.utsa.edu
Smashed under the treads of fate-
The future is now only a distant memory. ('Transition: Into the Unknown',1993)
------------------------------
Date: Wed, 11 Aug 1993 22:25:36 GMT
From: "Phil G. Fraering" <pgf@srl03.cacs.usl.edu>
Subject: Henry Spencer in the Slow Zone (Re: Ghost Wheels & HenrySpancer_Zoo)
Newsgroups: sci.space
neufeld@helios.physics.utoronto.ca (Christopher Neufeld) writes:
> Really? I was guessing that it was running in the Unthinking Depths.
Has to be. We don't have a feed up into the Slow Zone.
--
+-----------------------+
|"Standard disclaimer" |Clever quote will be back next week!
|pgf@srl03.cacs.usl.edu |
+-----------------------+
------------------------------
Date: Wed, 11 Aug 1993 15:26:28 GMT
From: Greg Cronau <gregc@cyberspace.org>
Subject: man-made meteor storm?
Newsgroups: sci.space
In article <249485$512@agate.berkeley.edu>,
>
>I won't address the question of wether you'll be able to see the
>re-entering pellets. I suspect not, from a first-order feeling.
>Things that size re-enter all the time (meteors) and I think you
>can only see multi-kg initial mass ones from the ground.
Multi-Kg meteoriods are the ones that actually make it to the ground, or
leave long, visible for a significant amount of time, trails across the sky.
Most common meteors, that just leave a quick flash of a trail and are visible
for less than a second, are caused by objects about the size of a grain
of sand.
---
Greg Cronau | gregc@edi.com (Pref.) |"Those who cannot remember
Computer Consultant/Joat | gregc@clif.ypsi.mi.us | the past, are doomed to
1405 NorthBrook Drv. | 76407,2311 (CI$) | repost it every month."
Ann Arbor MI. 48103-6166 | 313-741-0748 | -- Ed Vielmetti
------------------------------
Date: 11 Aug 93 14:15:38
From: Steinn Sigurdsson <steinly@topaz.ucsc.edu>
Subject: Mars Observer's First Photo
Newsgroups: sci.space,sci.astro,alt.sci.planetary
In article <DkB48B3w165w@1776.COM> bob@1776.COM (Bob Coe) writes:
aad@scr.siemens.com (Anthony A. Datri) writes:
>
> >The above demonstrates a profound ignorance of NASA. For some missions,
> >at least, the photos are available via FTP long before they're available
> >as hard-copy.
> The claim made at Gaspra was that various funding agencies deserved the
> first crack at images.
Sure. And just who do those "funding agencies" think put up their money?
Hmm, Japanese pension funds?
Maybe as a compromise each taxpayer could be sent one pixel
from every hundreth scientific image... they could print it
and frame it next to the rivets from the B-1 they also so
richly deserve.
| Steinn Sigurdsson |I saw two shooting stars last night |
| Lick Observatory |I wished on them but they were only satellites |
| steinly@lick.ucsc.edu |Is it wrong to wish on space hardware? |
| "standard disclaimer" |I wish, I wish, I wish you'd care - B.B. 1983 |
------------------------------
Date: Wed, 11 Aug 1993 19:12:33 GMT
From: Leigh Palmer <palmer@sfu.ca>
Subject: Mars Observer GIF Image
Newsgroups: sci.space,sci.astro,alt.sci.planetary
In article <6AUG199317481308@kelvin.jpl.nasa.gov> Ron Baalke,
baalke@kelvin.jpl.nasa.gov writes:
> The first image taken by the Mars Observer spacecraft of Mars is
>now available at the JPL Public Information access site in GIF format.
Information accompanying GIF:
"The resolution in this image is approximately 21.5 km (13.4 mi) per
picture element and Mars, roughly 6,800 km (4,200 miles) in diameter,
is about 315 picture elements across."
As entered in the jplinfo.jpl.nasa.gov ftp collection this GIF has an
information note attached which is misleading. It suggests that the GIF image
itself is of a planet 315 pixels in diameter, while the diameter on the GIF is
actually less than two thirds of that, measured in terms of GIF pixels.
The image posted is merely a scan of the press photo, and not original data.
The original data remain the property of the clever fellows who did the work
necessary to acquire them until a year after they are acquired.
This picture is one made for press release purposes and perhaps also to test
the performance of the instruments. May I respectfully suggest that a digital
version of such pictures is appropriate for release to the community early?
Even if that is not deemed wise under existing policies, may I request that
posted photos be scanned at the same resolution at which they were acquired?
Surely the loss in dynamic range due to the photographic process will be
enough to insure the integrity of the data, and since the photos themselves
are put into the public domain, any unscrupulous scientist who wished to scoop
a Mars Observer PI could scan them himself at the correct resolution.
Access to the Internet is expanding rapidly. The number of well-meaning
inquiring minds out there who want to use public domain software like "NIH
Image" for themselves on real data to see what they can see is increasing too.
Many of the newer users are students in schools with connection to the
Internet, and I can't imagine a better use of such pictures than to turn them
on. I still remember the thrill I got when I used NIH Image on a Voyager image
of Io and found the plume of a volcano on its limb which was invisible without
stretching the contrast. It matters little that it had been discovered years
before (by Linda Morabito at JPL); it was still thrilling. While that would
not likely be possible on a scanned photographic image, if you posted the
images at full resolution students could still play with something closer to
the real thing than they now can. I doubt that any scientific poaching will
result from such a change.
Perhaps the PIs themselves could authorize early release of a picture or two
to us hungry (and appreciative!) onlookers?
Leigh
------------------------------
Date: 11 Aug 1993 20:15:54 GMT
From: Tony Hamilton <thamilto@fnugget.intel.com>
Subject: Mars Observer GIF Image
Newsgroups: sci.space,sci.astro
I am one of many (I am sure) who has downloaded the Mars Observer image. It's
great. Question: have any more pictures been (or will they be) taken before
orbital insertion? If so, will they also be scanned and made available?
Also curious (and if this was posted and I missed it - apologies), what is
the magnfication of this image? I know how far away MO was when it took it,
but I'm too lazy to figure it out. Thanks.
Tony
------------------------------
Date: 11 Aug 1993 20:48 UT
From: Ron Baalke <baalke@kelvin.jpl.nasa.gov>
Subject: Mars Observer GIF Image
Newsgroups: sci.space,sci.astro
In article <24bk1q$h3q@ornews.intel.com>, thamilto@fnugget.intel.com (Tony Hamilton) writes...
>I am one of many (I am sure) who has downloaded the Mars Observer image. It's
>great. Question: have any more pictures been (or will they be) taken before
>orbital insertion? If so, will they also be scanned and made available?
>
There are no more images scheduled before orbit insertion, but there will
images taken during the in-orbit checkout period before formal mapping
begins in December. This will include images of Phobos (at Viking resolution
or possibly better) and Deimos. When the images gets released to the
public is up to the Principal Investigator, but I'd imagine he would release
some of them soon after they are transmitted back.
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | When given a choice between
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | two exciting things, choose
|_____|/ |_|/ |_____|/ | the one you haven't tried.
------------------------------
Date: Wed, 11 Aug 1993 20:40:09 GMT
From: & <keel@hera.astr.ua.edu>
Subject: Orbital Information
Newsgroups: sci.space
Specifically, a sun-synchronous orbit has the following properties.
This is taken verbatim from my Observational Astronomy lecture
notes, which accounts for all the TeXisms.
A particularly interested case is the {\it sun-synchronous
orbit}, useful for sky surveys as well as terrestrial observation systems.
This is an orbit that keeps the same orientation relative to the Earth-Sun
vector, using the oblateness of the Earth's mass distribution to precess
the orbit once per year in the appropriate direction. This means that,
for a spacecraft pointed outward above the terminator, fixed solar panels
will always face the Sun, and the field of view (if wide enough) will sweep
over the entire sky every 6 months. This has been used for the IRAS,
ROSAT, and EUVE missions.
For an oblate spheroidal planet with appropriate spherical-harmonic
moment $J$, the orbit precesses by
$$ \Delta \psi = 2 \pi J ({{R} \over {r}})^2 \cos i$$
per orbit, where $r$ is the semimajor axis, $R$ the Earth's radius,
and $i$ the orbital inclination to the equator. For the Earth,
$J = 1.637 \times 10^{-3}$, so this becomes numerically
$$ \Delta \psi = 0.0121 ({{R} \over {r}})^2 \cos i.$$
This was derived by Blitzer, Weisfield, and Wheelon, {\it J. Appl. Phys.}
27, 1141 (1956), and detailed by Thomson, {\it Introduction to Space
Dynamics} (Dover, 1961, 1986).
As a specific example, the {\it IRAS} satellite was in a 103-minute
orbit at an altitude about 900 km, so $r/R=1.23$. This gives the
required precession as $2 \pi$ radians per year = $2 \pi$ radians /
5106 orbits = $1.23 \times 10^{-3}$ radians per orbit, so the inclination
must be $98.85 ^\circ$, slightly retrograde to have the direction of
precession correct.
Even though the orbit appears to be tied to the
Earth's coordinate system, the wrapping around the celestial
sphere occurs in ecliptic coordinates, since the orbital plane
is instantaneously tied to the Earth-Sun vector.
------------------------------
Date: Wed, 11 Aug 1993 21:42:37 GMT
From: Andy Shearon <andy@mustang.aero.org>
Subject: Orbital Information
Newsgroups: sci.space
In article <kgO034O00WAxQ6JPFZ@andrew.cmu.edu>, Elliott Conan Evans <eeyore+@CMU.EDU> writes:
> I wish to put a fictional character in earth orbit so that the view
> out of the portholes is more-or-less a constant sunrise. The idea is
> to have my character experience a year long sunrise.
The orbit your roomate was discussing is a sun-synchronous orbit. This
means that the angle between the orbital plane and the sun remains
relatively constant. (This is due to the nodal regression of the orbit
caused by the oblateness of the earth & is a function of inclination and
mean altitude, if you want to look it up.) However, you could never
maintain a constant sunrise/sunset condition. This can be proven with
some basic geometry. With a sun-synch orbit, the sun is at some (nearly)
constant angle with the orbit plane. To be in a sunrise/sunset condition,
you need to have the earth between you and the sun. Therefore, in order to
be behind the earth at some point in the orbit, you must also be in front
of it (& the time in sunlight >> time in darkness >> time in sunrise/sunset
(technically called penumbra)) because of the geometry involved. i.e., if
the sun is at some angle to the orbit plane, say 90 degrees, the orbit will
be in continuous sunlight (Good for solar panels and tanning...). Reducing
this angle will eventually result in a sunrise/sunset pair for each orbital revolution.
But then again, you are writing a story and you could use a little artistic
license...
------------------------------
Date: 11 Aug 1993 22:45:36 GMT
From: George William Herbert <gwh@soda.berkeley.edu>
Subject: Simple Space Plane!
Newsgroups: sci.space
richard steven walz <rstevew@gorn.echo.com> wrote:
>gwh@soda.berkeley.edu (George William Herbert) writes:
>>nsmca@aurora.alaska.edu writes:
>>>Okay wierd idea time again:
>>>Ideas for a space plane, or atleast how to power it..
>>>Useing Kerosene (I think this will work, nicely if it does since Kerosense is
>>1/Mr(overall) = 0.0927
>------------------------
>Right on the money, George, but there's no harm in slinging second stages
>onto existing jets that have extra LOX to go higher with commercial jet
>fuel and then launching either piggybacked or underslung or bombayed
>vehicles. Then again, I haven't figured why they haven't used huge helium
>balloons to lift launch vehicles to a decent fraction of the way out of the
>largest part of air mass. They could even be reuseable! We DID actually get
>the X-15 to virtually the same altitude as the first suborbitals, and that
>was then with hydrazine and either ammonia or hydrogen peroxide
>concentrated. I see no reason we could put a lot of pieces of the space
>station up there cheaply using this stuff! I think we are a bit too shuttle
>focussed for good cargo delivery to orbit. And we DO have a missle slung
>under the F-15 now to shoot down satellites!
No harm, but not nearly enough good to make it worthwhile.
Mach 2 is only 600 m/sec, less than 10% of orbital velocity.
Even drop-launching* off a SR-71 won't get you a significant
boost, and introduces seperation difficulties, which are
not at all easy to deal with. A CIA M-12 drone carrier doing
a similar operation crashed when the drone which was
being launched crashed back into the plane, so launching off
SR-class platforms isn't that popular.
Altitude in and of itself is very little. About 1 km/sec is
spent in drag and G losses due to sea level launch, out of
around 9.5 km/sec total, so even starting at orbital height
and zero velocity you don't gain much over sea level.
The F-15 launching the ASAT missile was moving transonic,
in about a 45 degree climb, so it's not adding much velocity.
ASAT doesn't reach orbital velocity, just height...
It also is a three stage missile, so compararing it to
a SSTO concept is sort of strange. 8-)
These aren't at all new ideas. They're not bad ideas, but
so far nobody has shown that once you look at the details
they're better than the alternative straight-rockets.
The complexity involved almost always is worse for the
overall project than a larger initial rocket mass will be.
-george william herbert
Retro Aerospace
* "Drop" is technically inaccurate, as the D-21 drones launched off the
top of the M-12 (which is a SR-71 fammily plane).
------------------------------
Date: Wed, 11 Aug 1993 22:16:48 GMT
From: nsmca@ACAD3.ALASKA.EDU
Subject: Stage 1 to Mars!
Newsgroups: sci.space
Stage 1 to Mars:
Getting the supplies, material, people and such into orbit..
Heavy Lifter for heavy cargo, energina??
Personnel lisfter for personnel, shuttle for now, but a apollo or other man
rated vehicle can do..
Supplies for mars mission, stuff that doe snot becoem totally mush when fired
into space at 500+ Gs.. Namely stuff fired by a space gun, or other likely
quick and constant cargo. Namely things like water, rations, and such..
Space gun is good for puting cargo into space, if doen right, to set up a
stream of cargo into space.. But a heavy lifter can be used instead..
Once in orbit, start building/setup/whatever a station, need not be really
exciting, just basically a place to consolidate the personnel, cargo, supplies,
and instruments..
Once the Mars mission leave it can be turned into a ""real" space station, and
for the return voyage, as well as for satellite maintenance, and finally for
experiments..
In my mind, many experiments can be done better later on or elsewhere..
Lets have a functional space station/space dock.. and not a another scientist
experiment platform..
===
Ghost Wheel - nsmca@acad3.alaska.edu
------------------------------
Date: 11 Aug 1993 22:33:18 +0100
From: Mike C Holderness <mch@doc.ic.ac.uk>
Subject: Why the Shuttle will never be popular.
Newsgroups: sci.space
In article <CBKtrD.Lsn@eskimo.com> robs@eskimo.com (Rob Schultz) writes:
>
>Ok, how about this. The space shuttle started as a small pickup and midway
>through had folks try to turn it into a Lamborgini.
Uh? The way I heard it (and I'm positive it's been rehearsed to death here)
it started as a Triumph Spitfire (small, testosterone-laden, leaks in the
wet and can't get spares for love nor money, but quick) and ended up, post
Big Bird - carrying specification, as an Abrams M1 (large, ditto, ditto,
ditto and cumbersome).
=mike=
--
Anyone wants me to have an opinion on their behalf, they pay by the word.
mch@doc.ic.ac.uk
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End of Space Digest Volume 17 : Issue 016
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