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From: Henry Spencer <henry@zoo.toronto.edu>
Newsgroups: sci.space.science
Subject: Re: 2B .or. .not. 2B (a question on impacting probes)
Date: Wed, 1 May 1996 20:57:14 GMT

In article <4lpas6$18e@lace.colorado.edu> fcrary@rintintin.Colorado.EDU (Frank Crary) writes:
>Second, it would be very difficult to make observations.
>The angle between the spacecraft and the surface would
>be changing very rapidly...

In fact, back when Clementine's asteroid flyby was being planned, there
was a faction which wanted to aim for an impact.  "We're not going to
actually hit the thing anyway, the camera pointing is autonomous, and the
closer the better!"  This idea was scuttled partly by the problems caused
by extremely rapid angular motion at closest approach -- the limited slew
rate of the spacecraft would make it impossible to exploit the theoretical
resolution possible at very short distances.  (The other reason the idea
died was the thought of having to explain to Congress if they *did* happen
to hit the thing...)
-- 
Americans proved to be more bureaucratic           |       Henry Spencer
than I ever thought.  --Valery Ryumin, RKK Energia |   henry@zoo.toronto.edu



Date: Mon, 14 Sep 1992 21:44:04 GMT
From: Jordin Kare <jtk@s1.gov>
Subject: The BB Gun experiment (was Re: Asteroid explorer)
Newsgroups: sci.space

In article <pgf.716428199@srl02.cacs.usl.edu> pgf@srl02.cacs.usl.edu (Phil G. Fraering) writes:
>steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes:
>
>>As per the AO you get $17million (1992) for hardware, R&D,
>>staff etc, same again for launch; mission ops and data analysis
>>are extra. So, put together a CCD camera, a (IR?) spectrometer,
>>a low(medium?) gain antenna, redundant tape recorders, the best CPU
>>and memory that's flight qualified (is the intel chip qualified yet?)

Clementine (SDIO sensor test mission which will do a 2-month lunar mapping
mission followed by an asteroid flyby) will fly a MIPS R-3000-type processor
and 1.6 gigabit solid state memory.

>I've been thinking, though... what we really want from these
>asteroids is structural data. How could we get that?
>
>[Following idea Patent Pending Phil's Crazy Ideas Inc. ...] ;-)
>
>As Marvin Minsky pointed out a short while ago, small fuel tanks
>and large fuel tanks have the same mass to fuel mass ratio. So
>for an ion-drive powered probe you could with little mass overhead
>have lots of small tanks instead of one large tank for your
>fuel. Suppose for example you use six tanks.

Plumbing tends to make multiple small tanks less desirable, but the
differences are small.

>Every once in a while in the mission you need to "stage" and
>drop an empty fuel tank. Well, instead you use it: you keep
>it around until you're about to do a flyby of an asteroid.
>A small dogleg/jettision manuever, and you've slammed a fuel tank
>into the asteroid, giving your seismometer network lots of data.
>
>Oh, you don't have a seismometer network on the asteroid?
>Hmmm... what about using a laser rangefinder of some sort,
>to observe the "ringing" in the rock? Would this only be
>feasible for low probe flyby speeds?

Clementine is flying a state-of-the-art laser rangefinder, with
200 mJ laser pulses at up to 8 Hz for a limited number of pulses, or
1 Hz indefinitely.  It has a 500 km range and 10 m resolution,
(limited by electronics; could do 3-5 m with some engineering changes).
Not useful for observing seismic vibrations.  Unfortunately, interior
composition will probably require rendezvous for the foreseeable future.

What you _can_ do is use impacts to measure the composition of the
top few cm of surface, reaching below surface dust layers.  I proposed
an  experiment for Clementine, the Impact Plume SPectroscopy experiment,
which would have done this.  It was also called the BB gun experiment,
because it involved launching few-gram, BB sized projectiles from a
spring-powered launcher.  The BB impacts would occur just before
Clementine passed the asteroid, and the impact flares would be observed
spectroscopically.  It's not flying for several reasons, but it would
have been a fun experiment to do.

	Jordin Kare

	[Disclaimer:  any statements made here are my personal opinions
and do not represent the positions of LLNL, the University of California,
or the U.S. Department of Energy]


Date: 16 Jul 1993 03:01:33 GMT
From: Jordin Kare <jtk@s1.gov>
Subject: Clementine
Newsgroups: sci.space

In article <1214727f8@ofa123.fidonet.org>
David.Anderman@ofa123.fidonet.org writes:

>DA>>this is the *last chance* for us to see U.S. lunar exploration in this
>DA>>decade.
>RB>This isn't quite true.  Clementine will be launched next year and
>RB>orbit the moon for a couple of months.
>
>Yikes! I always forget about Clementine when talking about lunar missions.
>Clementine will orbit the moon next year, as part of a BMDO sensor test,
>but is not *really* a lunar scientific mission. ...


Clementine is not primarily a lunar science mission; scientific objectives
are formally secondary to BMDO objectives.  In particular, the sensors
carried are not the first choices of scientists, either grossly (no
gamma ray spectrometer) or in detail (not enough filter bands --
although upgrading from 6-position to 8-10 position filter wheels was
one of the "we just don't quite have time/$$ to do" options that
was discussed for some time).

However, there's a great deal of interest in the planetary science
community in the science Clementine _will_ do, and the scientistss
have been much involved in planning the mission operations  and
defining those aspects of the instruments and spacecraft that they could.

[For those not familiar, Clementine is a small spacecraft to be
launched next January on a refurbished Titan IIG from Vandenberg.
It will be boosted by a solid-motor transfer stage into a lunar
transfer orbit.  It will make 2-1/2 "phasing loops" - orbits around
Earth - while observing the discarded transfer stage, then
go into Lunar orbit.  It will spend 2 months mapping the lunar surface
in the visual and IR bands with ~100 m resolution, as well as taking
spot images with ~10 m resolution and ranging the surface with
a laser rangefinder with ~10 meter resolution.

After the lunar mapping, Clementine will exit Lunar orbit, do an
Earth flyby and lunar gravity assist maneuver, and head out for
a flyby of Geographos, an Earth-crossing asteroid, in August 94.
The flyby will be at 100 km, and will provide (all things going well)
~2 meter resolution images of the asteroid.

Clementine carries 5 LLNL-developed sensors:
	UV/Visible camera with 6 filters
	Near IR camera (1-2.5 microns) with 6 filters
	Far IR camera (8-10 microns)
	High resolution camera (1 m f.l., 18 microradian IFOV)
	Laser rangefinder integrated with Hires camera
	Plus 2 LLNL Star trackers to provide navigation data

Total mass of LLNL sensor package is 7 kg.]

Keep your fingers crossed, folks... We're busy assembling cameras
even as I type...

	Jordin Kare


Date: 22 Jul 1993 20:36:59 GMT
From: Jordin Kare <jtk@s1.gov>
Subject: Clementine
Newsgroups: sci.space

In article <1416728cd@ofa123.fidonet.org>
David.Anderman@ofa123.fidonet.org writes:

>HS>In article <1214727f8@ofa123.fidonet.org>
>HS>David.Anderman@ofa123.fidonet.org writes:
>HS>>Clementine will orbit the moon next year, as part of a BMDO sensor
>HS>test, but is not *really* a lunar scientific mission...
>
>HS>Actually, it's not a bad lunar scientific mission, within its limits.
>HS> The major limit is that its sensors are not optimized for lunar
>HS>science except in small ways (like choice of filters).  In particular,
>HS?it's a purely optical mission, with no gamma/neutron instruments.
>
>I am told that it's optics are inferior to the normal NASA optics in
>several ways:
>
>sensitivity to radiation is high (meaning radiation in the space
>environment will tend to degrade the images)

This is not correct.  Clementine's instruments are designed for a
20 krad radiation dose.  The primary differences between the Clementine
instruments and their sounding-rocket predecessors are improved
thermal management and improved radiation resistance, including use of
radiation-resistant glasses in optics.  Current CCD's do suffer some
noise increase due to radiation, but not enough to affect the Clementine
data; we are testing new "MPP" CCD's which are hard to 100 krad.

>and the resolution is comparable to a Lunar Orbiter (as in the Lunar
>Orbiter from the 1960's).

There is some high resolution Lunar Orbiter data, but it's inaccessible
(stored on film and/or obsolete-format mag tape) (efforts are being
made to scan film and read old tapes to produce "modern" digitized
images), covers only a portion of the Lunar surface, is single-color
and non-photometric, and does not match the resolution of the
Clementine high-resolution camera.

>I am told that this is due to its unique mission (to test BMDO military
>sensors) - the optics are extremely small and light, but not to the normal
>NASA specs.

The optics are comparable in performance to what NASA would fly/has
flown in the same size range; we're actually more limited by data
transmission bandwidth than by optics in resolution (i.e., the high res
camera will take only a few percent of the frames it's capable of taking,
because running it continuously would swamp our memory and transmission
rate).  The major difference from a NASA instrument is the lack of
on-board calibration; Clementine will have to rely on pre-launch
calibration supplemented by various natural sources (stars, averaged
frames of lunar plains, etc.)

>I would love to be corrected on this - Clementine is a wonderful mission,
>but I don't want to get our hopes too high that this will be the Lunar
>Orbiter that we have all waited 21 years for.


Well, it _is_ a shame we couldn't include a gamma ray spectrometer....

BTW, unlike a NASA mission, the data from Clementine will _not_ be
private to the PI's for some period.  In fact, the data will be
transmitted unencoded, and could be received by many well-equipped
hams.  I have so far failed to establish contact with the AMSAT folks
to try to get this made an actual part of the mission, but if anyone
can get the right AMSAT folks to give me a call, please do so.

	Jordin Kare


Date: 22 Jul 1993 20:47:04 GMT
From: Jordin Kare <jtk@s1.gov>
Subject: Clementine
Newsgroups: sci.space

In article <21JUL199310592311@vx.cis.umn.edu> soc1070@vx.cis.umn.edu (Tim
Harincar) writes:

>Some questions about the science objectives of the mission:
>How much of the surface is intended to be mapped? Poles included?

The entire surface of the moon, including both poles, will be imaged
over a 2-month period.  (There's a small area near one pole that will be
in "perpetual dark" during this time).  The elliptical orbit means
the resolution at the poles will be somewhat worse (about 2x) than
in low latitudes.  The laser rangefinder will (we hope) obtain
surface altitude measurements over about 120 degrees of latitude.

>Do the 10m resloution spot images include any 'artificial' features
>(ie Ranger, Lunar Orbiter, LM Ascent stage, S-IV stage impact sites)?

There will be some effort to target interesting sites, but operational
limits may keep it to a handful (you lose mapping when you rotate the
satellite to look at a specific site, unless you happen to pass right
over it).

>I think the impact sites would be interesting because you have an object
>of known size, shape, mass, velocity and you can see what kind of dent
>it made.
>
>How about other artifacts - Apollo sites, Lunakhod sites, Surveyors, etc.
>Apollo & Lunakhod sould be easy since the astronauts turned up so much
>new soil with there boots & rovers, should be good contrast... Mostly,
>these images would be cool PR, I don't know how much science value they'd
>have.

There were suggestions that we do at least a few orbits at very low
perilune (<<100 km above the surface) and try to get a picture with
enough resolution to show the flag "waving" at one of the Apollo sites.
Potentially possible, but probably will not be done.
>
>BTW, according to _Robot Explorers_ by kenneth Gatland, the Lunar Orbiter's
>cameras had resoultions of 487m (wide angle) and 60m (telephoto). According
>to what Jordin Kare of LLNL posted, Clementine's cameras are ~100m and
>about 10m resolutions - better in both cases. So the quality of data
>should be pretty good.
>
>tim harincar

We hope so...
	Jordin



Date: 3 Dec 1993 17:59:29 GMT
From: Jordin Kare <jtk@s1.gov>
Subject: lunar Pegasus missions (was towers)
Newsgroups: sci.space

In article <1993Nov27.211331.22155@aio.jsc.nasa.gov> kjenks@jsc.nasa.gov
(Ken Jenks [NASA]) writes:

>Well, sci.spacers.  What instruments would you want to put around the
>moon in the 5-15 kg range?  Maybe have four launches, with three
>of them being relay sats and the fourth a science payload.  How
>about a small telescope, a CCD array and a video transmitter?  What
>could we do with that?
>
>-- Ken Jenks, NASA
>      kjenks@gothamcity.jsc.nasa.gov  (713) 483-4368


Roughly what Clementine is doing with a 7 kg instrument package this
spring:  surface mapping and multiband imaging.  Unless you can get
DSN-grade tracking equipment, you can't do gravity mapping.  X-ray
fluorescence and gamma spectrometry pretty much require larger instruments.
So it's a bit hard to see what the point is.

Much more fun:  design a 5 kg microrover and set it down on the surface....

	Jordin Kare


Date: 23 Jan 1994 01:29:30 GMT
From: Jordin Kare <jtk@s1.gov>
Subject: DSPSE Clementine information request
Newsgroups: sci.space

In article <759242068snz@sarnia.demon.co.uk> steve@sarnia.demon.co.uk writes:
>In article <wilson.759186396@moonshine> wilson@moonshine.llnl.gov writes:
>>
>> I don't know of any mailing list, or faq.  I was going to set up a ftp
>> site sometime in the next few days (time is a bit short just now), for
>> public info relating to clementine.  Do you have any specific questions?
>> mikew@s1.gov  Systems Manager, Advanced Technology Program, LLNL
>>
>Yes, lots, but here's a few to start off with;

I'll fill in with a couple of answers...	Jordin

>Q1.     What will the address of your ftp-site be?

Mike gets to answer this one...

>Q2.     Are there any gifs, jpegs etc. of the spacecraft available?

I'm not aware of any, but no doubt something can be scanned in.  Mike?

>Q3.     What sort of orbit will the "Interstage Adapter" be put
>        into, and how long is it expected to survive?

The interstage adapter goes into (approximately) a lunar transfer orbit,
with perigee at something like 200 km and apogee at nearly lunar distance.
It's expected to survive for at least several orbits, and has been
instrumented to measure the radiation sensitivity of some hardware
on its passages thru the Van Allen belts.  I don't believe it's expected
to survive more than a few weeks because the orbit will be strongly
perturbed by the Moon, but I'm way out of date on the details, so I
could be wrong...

>Q4.     What is the expected resolution of Clementine's images of
>        the Moon and Geographos?

The high resolution camera will have a pixel size of approximately
8 meters at perilune, but will image only a small fraction of the
lunar surface (in 3 visible-light colors) and the actual resolution
will be somewhat degraded by the image intensifier; figure 20 meter
resolution at perilune and about 30 meters near the poles.  (Perilune
is at ~400 km, and will be at +30 latitude for 1 month and -30 for one).

The UV/Visible camera will have a perilune pixel size of ~100 meters and will
image the entire Moon in 5 colors in the visible (actually slightly-UV
to slightly-IR).  The Near IR camera will image the entire moon with
~150 meter perilune resolution in the 1 - 2 micron range.  The Far IR
camera will image a fraction of the moon with ~50 meter resolution at
10 microns.

The laser rangefinder should generate profiles of the Lunar surface with
40 meter accuracy over most of the surface, but will not work at the poles.
The profiles will be sampled at about 2 km intervals along track, and
several 10's of km from track to track.

>Q5.     Will these images be made available to the Internet public?

I'm sure sample images will be available, but the data volume is
enormous.  There will probably be a mechanism for browsing the data
set and downloading images over Internet; I just don't know how long
it will take to set up.

>Q6.     When is Clementine due to encounter Moon and then asteroid?

Launch is currently (Sat. afternoon) set for 8:26 a.m. Tuesday.  Lunar
insertion is ~22 Feb., mapping begins a few days later.
Mapping continues for 2 months.  Lunar departure is May 3, and Geographos
flyby is late August.  (dates may have changed by a few days since
the schedule I'm looking at....)


	Jordin Kare	jtk@s1.gov	erstwhile Clementine Mission Planer
					(hey, that's what the Org chart said!)


Date: 23 Jan 1994 18:37:32 GMT
From: Jordin Kare <jtk@s1.gov>
Subject: DSPSE Clementine information request
Newsgroups: sci.space

In article <2hsmgkINN6f3@watt.cs.unc.edu> leech@cs.unc.edu (Jon Leech) writes:
>In article <2hsjtq$73o@s1.gov> jtk@s1.gov (Jordin Kare) writes:
>>
>>I'm sure sample [Clementine] images will be available, but the data volume is
>>enormous.  There will probably be a mechanism for browsing the data
>>set and downloading images over Internet; I just don't know how long
>>it will take to set up.
>
>    How about pressing CD-ROMs? Any funding for that? Or maybe you could
>hand the data over to whomever at NASA (NSSDC?) handles that for their
>planetary missions?


There has been considerable thought given to distribution of the
Clementine data set, and to integrating it into the NASA planetary
mission data system.  It's been many, er, moons, since I was in on
those discussions, but my recollection is that there were plans to
reproduce the data on CD-ROM, as the least expensive way to distribute
it.  Most of the questions involved formatting, and,e.g., whether
to include the raw data or only the data after calibration (camera
gain correction,etc.).  Bear in mind that Clementine will send down
something like 10^11 bits of images from the Moon, so a full
data set would be ~200 CD-ROM's!

	Jordin


Date: 7 Feb 1994 21:06:05 GMT
From: Jordin Kare <jtk@s1.gov>
Subject: Clementine Computers.
Newsgroups: sci.space

In article <2iu2jm$alf@access2.digex.net> prb@access2.digex.net (Pat) writes:
>Lou tells us the Clementine uses a 1750A  and a R3081.  I don't know the
>R3081,  but Gack a 1750A.  that's as old as the hills.  please don't
>tell me it's programmed is CMS-2  or Jovial....
>
>couldn't the in 1992-3  get something a little better hten the 1750A?


The 1750RH (rad hard) processor was the best fully Mil-Std space-qualified
processor available for Clementine, as well as being a processor that NRL
(the spacecraft integrator) had used before and was comfortable with.
It runs "mission critical" software (housekeeping, command&control functions)
for which it is quite adequate, and for which the demonstrated reliability
was considered extremely important.  I'm not sure what the bulk of the
actual code was written in, but there is a C compiler available for
the 1750 that was used for at least some ofthe development.

The R3081 is a rad hard variant of the R3000 RISC processor, and much
closer to the current state of the art.  It is used as the Sensor
Interface Processor, doing image processing (including processing
Star Tracker images for attitude control) and is programmed in C; it
runs VxWorks, a commercial operating system.

The Clementine bus structure was designed such that either processor
could run the satellite if the other failed.  This did involve some
interesting development, notably porting the Star Tracker algorithms
to the 1750.

A feature of the Clementine software development was the use of SCL,
the Spacecraft Command Language, which is a high-level language
developed expressly for operating spacecraft, with appropriate
ability to schedule and prioritize events that may be driven by
spacecraft resources (power, instrument availability) or external
events both predictable (sunrise) and unpredictable (component failure)...

LLNL has flown sounding-rocket missions using only R3000-series
processors, and I believe the local preference would be to fly
future satellites without having to worry about the limitations
of 1750s and the like ... but there's also much to be said for
using familiar, well-tested hardware when it will do the job...

	Jordin Kare



Date: 9 Feb 1994 03:30:55 GMT
From: Jordin Kare <jtk@s1.gov>
Subject: pronounciation of "Clementine"
Newsgroups: sci.astro,sci.space,sci.space.science

In article <9402090028.AA24758@cs.utexas.edu> obyrne@cp.dias.ie (Chris O'Byrne) writes:
>I had assumed the probe's name was pronounced "clem en TINE" (as in
>fork tine and indeed the song "oh my darling Clementine") but on
>Patrick Moore's Sky at Night TV programme he pronounced it "clem en
>teen ah" or "clem en teen eh".
>
>What's the correct pronounciation?

Clem en TINE.  Ghu knows where Patrick Moore's alternative came from.
Possibly the same place all the politicians get "nuc-u-lar" :-)

>How did the probe come to get this name in the first place?

Stu Nozette, who initially promoted the mission concept at SDIO,
 was thinking about asteroid mining (miner '49er's) and
about asteroid flybys (after which the spacecraft is "lost and gone
forever") and decided to call the (at that time embryonic idea for a)
mission "Clementine".  For a while, NRL made a determined effort to
use a more "official" name, DSPSE, the Deep Space Program Science
Experiment, but that got pronounced "Dipsy", and everyone else
kept calling it Clementine, so they eventually gave up...
(No doubt the DSPSE satellite should have used a computer with a SCSI bus :-)

Incidentally, the official Clementine logo shows a blond-haired woman
(Clementine) holding a shield (part of SDIO's logo), with a portion of
the moon in the lower foreground and an American flag sticking out of the
moon.  In the background is a brown rock (Geographos, presumably),
with a large "#9" stamped on it:  "And her shoes were Number Nine"

>-David Moore BSc FRAS, Editor, ASTRONOMY & SPACE magazine published by:
> Astronomy Ireland, P.O.Box 2888, Dublin 1, Ireland. VISA/MC accepted.


"In a lab up near the Beltway
Where the weather's seldom fine,
Lived a feller, an NRL'er
And his satellite, Clementine

	Oh, my darling, Oh my darling,
	Oh, my satellite, Clementine!
	You are launched and gone forever
	Send some data, Clementine!"

		Jordin (Bard of the Spaceways) Kare


Date: 1 Mar 1994 00:31:02 GMT
From: Jordin Kare <jtk@s1.gov>
Subject: Clementine???
Newsgroups: sci.space

marting@col.hp.com (Martin Guth) writes:
>Magnus Olsson (magnus@thep.lu.se) wrote:
>: I haven't seen anything on this newsgroup about Clementine for a while.
>: According to an article in Astronomy, it should have begun lunar mapping
>: a few days ago. Anybody know whether it's on schedule?
>
>Last I heard a few days ago from TV news is that it's in orbit around the moon.
>No word as to whether it's working or not. I really don't know what the big
>secret is, other than it's a Defense Dept. mission (partly, anyway).
>
>Martin Guth  marting@col.hp.com

No big secret, just a strong desire not to put out premature (mis)information
and (I suspect) bureaucratic delays in a system that hasn't done
anything like this before.  I believe the information drought will
be relieved once lunar mapping is well started and people involved can
think about other things for a while.

Meanwhile, to reassure the Net, I will take the liberty of stating that
as of last Thursday -- when I had a chance to stop in at the
operations center -- everything was fine.  Clementine was in Lunar orbit
and sending down images that looked very nice to my (untrained) eye.
All instruments were working.  Mapping hadn't started (there was some
"checkout and tuneup" time built in to the schedule) but
was expected to in the next few days.

A spectacular success so far, in my opinion.  Keep your fingers
crossed and stay tuned.

	Jordin ("Was that a _McDonalds_ in that crater?!") Kare


From: jtk@s1.gov (Jordin Kare)
Subject: Re: Stirling cycle in space
Date: 23 May 1994 20:11:50 GMT

In article <Cq663o.9I2@zoo.toronto.edu> henry@zoo.toronto.edu (Henry
Spencer) writes:

>In article <2rj4u1$8d3@unix.sri.com> wohlsen@sri.com writes:
>> ... whether engines based on the stirling cycle have been used in
>> space...
>
>Stirling-cycle coolers have been used, I believe, for cooling sensors.
>Nobody's used a Stirling cycle for power generation that I know of.

The Clementine IR cameras use
Stirling coolers.  The Clementine coolers are among the lightest to have
substantial lifetime.  The main limit on Stirling systems is that they
use sliding seals, and therefore have limited lifetime and a relatively
high risk of failure.  The Clem coolers have, as I recall, a 5000 hr
rated MTBF (and are actually probably good for substantially more than that)
but use relatively recently-developed flexural bearings.  Oxford Engineering
makes some considerably heavier long-life Stirling coolers that are
baselined for some future satellite systems (DOE's MTI satellite, e.g.).
There's also a problem with vibration, such that many systems must
use opposed-pair coolers to get low enough vibration levels.  (The
Clem coolers were singles, but small and well-balanced, and Clem was
not an extremely high-resolution system).

Incidentally, the Clem coolers were derived from technology developed
for cooling IR sensors for air-to-air missiles, FLIR, nd the like, where
run times are minutes to hours...

It is possible to build "clearance seal", flex-bearing coolers with
very long lifetime, but expensive and relatively untested technology.

Notwithstanding all of the above, NASA Lewis, among others, have
proposed using Stirling-cycle generators with radioisotope heaters
as a high-efficiency alternative to the abysmally inefficient thermoelectric
converters now used in RTG's for deep space probes.  The system mass
is about the same as for thermoelectrics, but the amount of
plutonium needed is about 1/3 as large.  (I've been known to refer to
Stirling/radioisotope power systems as "radiodynamic power", which
has a wonderful '30's SF sound to it, doesn;t it?)

>There also has been only very limited interest in solar-dynamic power
>generation of any kind, since people tend to mistrust moving parts and
>circulating fluids compared to the relative simplicity of solar arrays.

There's more to it.... Another problem is that solar arrays will give you
_some_ power even if you lose attitude control; concentrator-based
solar-dynamic systems will shut down completely.  And, of course,
solar-dynamic lacks "heritage" (the usual chicken and egg problem
for advanced space technology).

	Jordin (a Stirling character) Kare


From: eder@hsvaic.boeing.com (Dani Eder)
Subject: Re: Clementine
Date: 31 May 94 17:40:33 GMT

> HALAN@whqvax.picker.com (JOHN HALAN) writes:
>
>As I am curious to hear the justification of our most renoun and august
>skeptics, I ponder the following questions:
>
> 1.  Why in the world does the US military NEED to launch a satellite to take
>     over 1,500,000 high resolution images of the surface of the moon?!?!?!
>
> 2.  Why does the US military NEED to orbit a satellite around the moon in
>     order to perform Advanced Ballistic Missile Defense Technology testing?!?

I'll take a stab at answering these questions.  My answers don't
come from any special knowledge about Clementime, but they do
draw on over a decade of space work, including supporting SDI
projects.

(1) Taking pictures of the Moon was incidental to the primary mission:
an engineering test of a bunch of new military space hardware.  Since some
of the new equipment was sensors, including cameras, you needed to take
pictures of _something_.  The Moon probably looks a lot more like an
ICBM warhead (dark grey) than the Earth, so it makes a better target.

(2) One of the things they were testing for was how the equipment stands
up to radiation.  Once you were in an elliptical orbit that goes
through the Radiation Belts, the velocity increment to go to the
Moon was pretty small.  And they had a propulsion and guidance system to
test, so the extra cost to go to the Moon was even smaller.  Targeting
a planetary body is a very sensitive test of the accuracy of a guidance
system since the body's gravity amplifies any initial error in the
trajectory.

> 3.  What is it that the US military NEEDS to test while in orbit around the
>     moon, that can't be tested while in orbit around the Earth?
>     (Perhaps particle beam Star Wars technology on the dark side?)

(3) See answer (1)

> 4.  Why was the military allowed to get away with this project?  Except for
>     ICBMs and spy satellites, the military is not supposed to be in space.
>     Why isn't this project being carried on by the "civilian" NASA?

(4) Even if your argument that the military only has a few functions in
spac is correct, surely you allow the testing of improved spy satellite
hardware?


> 5.  Just what is the Balistic Misslle Defense Organization, and why do they
>     have the power and authority to send a satellite to the moon?

(5) It is an agency of the Defense Department commanded by a two or
three star general.  They have the same power delegated to them by US Law
to handle military space activities that NASA has for civilian space
activities.
There is not any treaty that prohibits them from _all_ presence in
planetary space (as opposed to Earth orbit space).  Certain things, like
weapons of mass destruction _are_ prohibited.


> 6.  Does anyone actually believe that Clementine was actually thrown together
>     on a shoestring budget and it ONLY cost $100 Million dollars?

(6) That sentence is self-contradictory.  No normal person considers
$100 million a 'shoestring', but in the world of aerospace it is a reasonable
amount of money.  It's about what it costs to buy a moderately large
commercial communications satellite.  Clementine is smaller than such
a comsat, but then it also has more unique, one-off equipment, so I don't
see any reason to question the figure.  Sure, the Hubble Telescope cost
$1.4 billion, but it's also about 20 times the size of Clemetine.

The R&D behind the new sensors probably amounts to several times the
Clementine budget, but that's a different category of spending.  The $100
million is claimed to cover design and construction of Clementine
itself.



> 7.  What is so important on the moon that the militaty would rather have
>     1.5 Million high-res images of the moon, than say, 5 brand spanking
>     new F-15E fighters?

(7) Check your price list, $100 million only buys you 2 new F-15E's.
And if you are so hot on conspiracy theories, how do you know that Clemetine
isn't a cover for a future military base on the Moon?  Or a search
for Enemy bases on the Moon?  Considering the billions per year that
go into Earthly reconnaisance, sending one small probe to the Moon
just to make sure nobody else is using it for a base seems to be a reasonable
idea.  And what about sending an ICBM around the Moon, and deploying the
warheads and decoys back there where nobody can see what your doing?
If you watch really closely an ICBM in flight near the Earth might give
away the difference (you could see the decoy balloons inflating or
calculate the object masses by the burn times for the bus to position the MIRV
warheads.


-----

More generally, I believe that the SDIO, now BMDO, and the military
generally, have done at least as much as NASA in advancing space
development.  They probably have wasted almost as much money as NASA.
Both are agencies of the US government, so what difference does
it make who does what?  For that matter, most of the astronaut corps
is military personnel anyway, and the DOD funds almost a billion
dollars a year of basic science, so the dividing line is not as clear
as you might think.

Dani Eder


--
Dani Eder/Rt 1 Box 188-2/Athens AL 35611/(205)232-7467


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