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Date: Mon, 8 Feb 93 07:45:08
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V16 #136
To: Space Digest Readers
Precedence: bulk
Space Digest Mon, 8 Feb 93 Volume 16 : Issue 136
Today's Topics:
Clinton's Promises (space) in Charlotte Observer
Meteor Riding/Netting (lets go fishing)
Mir Mirror
NASA Approved copy of TRASYS for SGI?
Riding Comets
Sabatier Reactors.
So what's happened to Henry Spencer?
Space Digest V16 #093
Space Grown Semiconductors
Units and Star Trek
Using off-the-shelf-components
Welcome to the Space Digest!! Please send your messages to
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----------------------------------------------------------------------
Date: Thu, 4 Feb 1993 21:59:42 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: Clinton's Promises (space) in Charlotte Observer
Newsgroups: sci.space
In article <1k6beeINNgtf@mojo.eng.umd.edu> sysmgr@king.eng.umd.edu writes:
>>... kill SS Fred and offer $10B, tax-free, to the
>>first US corporation or consortium to put a station on orbit and keep it
>>staffed by at least X people for a year and day. He should also offer $5B to
>>the second corporation/consortium to do the same thing...
>
> A) Who owns possession of the technology used to develop the station?
US industry, which the government is supposed to be helping.
Besides, why do you care? The idea is to get results, not "technology".
> B) Who owns the data?
What data? Oh, you want the station to send back data? Tell them that
once the station is up there, the government will pay for the data at
specified prices, after which the government will (of course) own it.
> C) How do you set the damned thing up without using goverment help
> in the first place? Guess who owns all the big launch facilities.
Commercial launch providers use those facilities routinely now (although
admittedly not without a lot of stupid hassles). Create enough of a market
and maybe some of the proposals for commercial launch sites will actually
happen. It sure would be useful.
> D) Does it have to be a U.S. corp? What if I use off-shore tech, say
> get the Italians into building my living modules?
Practical politics would probably dictate restricting it to US companies.
Who cares whether they use off-shore technology? If your priority really
is technology rather than an operational space station, write in a
requirement that any off-shore procurement of major subassemblies must
include the technology used to build them.
--
C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology
effect since OS/360. | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: Thu, 4 Feb 1993 20:44:22 GMT
From: Nick Szabo <szabo@techbook.com>
Subject: Meteor Riding/Netting (lets go fishing)
Newsgroups: sci.space
jbh55289@uxa.cso.uiuc.edu (Josh Hopkins) writes:
>Now picture yourself throwing a net in front of one of the
>hypersonic battleships.
Let's throw out the net or grappler at hypervelocity, so that its
delta-v with the asteroid is very low. If the delta-v between spacecraft
and asteroid is 4.0 km/s, we might throw the grappler back from the
spacecraft at 3.99 km/s. It then snags the asteroid at 10 m/s,
and a _very long_ bungee chord absorbs the remaining 3,990 m/s over
many minutes, until the spacecraft and asteroid have matched velocities.
Part of the energy can also be absorbed by a friction reel and heat
dissipation system, or by spinning up a flywheel which can then
be used to launch payloads the other way. (This gets back to the
rotating tether idea, which might also be used here).
The chord will be very heavy. If it's heavier than the spacecraft,
it takes less energy to move the spacecraft than to launch the
bungee chord & grappler. So, this technique works best if it is deployed
from the asteroid and reused. To save launch costs, we could use
chemical microreactors to make the bungee chords from cometary organics.
Bungee braking! :-)
--
Nick Szabo szabo@techboook.com
------------------------------
Date: Thu, 4 Feb 93 22:27:11 GMT
From: Leonard Spani <spani@mprgate.mpr.ca>
Subject: Mir Mirror
Newsgroups: sci.space
In article <4003@mowgli.mdavcr.mda.ca>, faubert@mdavcr.mda.ca (David M. Faubert) writes:
|> Hi,
|>
|> On the radio this morning I heard that the Russian mirror experiment could
|> be seen in the west from Vancouver, where I am. I went outside and, sure
|> enough, there was this extremelely bright light in the west. By extremely,
|> I mean around magnitude -5 I suppose. It was flickering slightly and it
|> was slightly yellow, which is what one would expect from a light outside
|> the atmosphere that low on the horizon.
|>
|> Did anyone else see it? I would like to have some confirmation that the
|> thing I saw was the mirror and not something else like another UFO.
|>
Yeah.. I saw something too.
It was between 6:30pm and 7:30pm Vancouver time when I was driving home
from work. I couldn't get a good look at it, but it was definitely unusual
and didn't look like an aircraft or anything. It was very bright and seemed
to flicker a bit. The colour was different from the "usual star colour" but
I couldn't put a specific colour on it. It was not Venus, or whatever that
extremely bright "star" is that has been in the western sky lately. It
also appeared bigger than your average star, and slightly rectangular
(wider than it was high), but that may have been an illusion based on its
brightness. My first impression was that it was an unusual aircraft because
its lights were exceptionally bright and didn't blink.
I'm not sure of the direction (I was paying more attention to the
road), but I would *guess* it was more-or-less south in the sky. It
appeared to move very slowly, but that could be nonsense because I was
always moving when I was watching it. It was unusual enough that I would
call it a UFO (by strict definition), but the MIR mirror certainly sounds
like a good explanation. Could I have seen the mirror between 6:30pm and
7:30pm? Also, the object seemed to appear and disappear, would the mirror
do this? (A more likely explanation is that I simply lost sight of it
while driving and couldn't find it again when I looked back ;^)
When I got home, I couldn't find it anymore ;^(
|>
|>
|> Dave
|>
|>
|>
|>
Leonard.
--
***********************************************************************
| Leonard E. Spani | //!?\\ | (disclaimer-p) |
| spani@mprgate.mpr.ca | \\?!// | t |
*****************-<( "everybody thinks I'm paranoid" )>-***************
------------------------------
Date: 4 Feb 93 20:57:18 GMT
From: Michael McCulloch <lmccullo@nyx.cs.du.edu>
Subject: NASA Approved copy of TRASYS for SGI?
Newsgroups: sci.space
I'm looking for a NASA approved source for TRASYS. We have several SGI's
running IRIX 4.0.5.
Please don't direct me to COSMIC -- since the versions they release are
for VAX or CONVEX computers. Even with source code, some incompatibilities
are encountered if trying to port to SGI's (MIPS architecture).
Please respond directly to mmcculloch@nebula.tbe.com .
Michael McCulloch
Huntsville, AL
Teledyne Brown Engineering
------------------------------
From: Victor Wood <RM4Y@VM.OP.DLR.DE>
Subject: Riding Comets
Terry Ford asks in a message about the possibility of hitching a lift
on a comet.
Well, I suppose you could, but why bother? Not much fuel is used
in going over millions of KM of space. Most fuel is used in the
powering of electronic systems, transmitters and (any) experiments.
I think there is a project to cruise beside and land on a comet planned
but I can not think what it is called. I think, if I remember correctly,
it is suppose to take a comet core sample and return it to earth in a
fridge.
Im not to sure about that though. Maybe someone at NASA or ESA could
comment?
Victor Wood |
|
RM4Y@VM.OP.DLR.DE | "Life is a 50 pence paperback"
|
ROSAT Control K4 |
German Space Operations Center |
Muenchenerstr. 20 |
D-W8031 Oberpfaffenhofen |
+49 81 53 28 14 22
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
------------------------------
Date: Thu, 4 Feb 1993 19:46:45 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: Sabatier Reactors.
Newsgroups: sci.space
References: <1jutp0INNacf@digex.digex.com> <24JAN199320503892@judy.uh.edu> <1993Jan26.030319.11373@iti.org>
Organization: U of Toronto Zoology
Lines: 26
Sender: news@CRABAPPLE.SRV.CS.CMU.EDU
Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU
In article <1993Jan26.030319.11373@iti.org> aws@iti.org (Allen W. Sherzer) writes:
>... they will be using hydrazine thrusters. BTW, these thrusters are the
>single heviest items to be returned to Earth. They must be returned intact
>since it would be too dangerous to re-fuel them in orbit.
The Soviets/Russians have only been doing such refuelling for ten years,
after all...
>Dennis, The Wake Shield facility would cost NASA $93 million to build
>(according to their cost model). A private company is building it for
>$11 million. Spacehab would have costed NASA $1.1 billion (again,
>with their costing model). A private company is doing it for $153
>million. NASA would have taken eight years and $1 billion to build
>the same DCX vehicle which McD is building in two years for $60 million.
Also to the point, I'm told that if you put a standard piece of lab
equipment -- the sort of thing that might plausibly go into a space
station lab module -- through NASA's what-it-should-cost model, and
then compare to the actual commercial price, you begin to understand
why everything NASA does is so expensive. Forget cost overruns; even
when everything goes right, NASA pays far more than it should, because
its own cost models say things ought to cost that much, and no supplier
in his right mind is going to argue.
--
C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology
effect since OS/360. | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: Thu, 4 Feb 1993 21:48:38 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: So what's happened to Henry Spencer?
Newsgroups: sci.space
I wrote:
>Second, I visited Edwards and Dryden, and finally met Mary Shafer.
>It was a great visit, even though I wasn't entirely well by that point,
>and Mary's every bit as nice in person as on the net.
I should say, though, that Mary did one unkind thing: she warned the
Dryden tour guide (Mary seems to know everyone at Dryden) not to let me
try to sneak off with one of the SR-71s. Rats. I was looking forward
to making a run for the border at Mach 3...
--
C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology
effect since OS/360. | henry@zoo.toronto.edu utzoo!henry
------------------------------
From: BRIGGSP@Citadel.edu
Subject: Space Digest V16 #093
Rich Kolker <rkolker@nuchat.sccsi.com> writes:
>All these kids... I was in elementary school, I was in nursary school, geez :-).<
Amen, bro. Until this very moment I thought I was still young. But I was
not TAKING a class when the Challenger explosion occurred, I was TEACHING one.
The deartment lab tech had the TV tuned in during the passing period between
classes, so I got to see the replay of "Go at throttle-up" and then went into
class to teach Mechanics.
Now the JFK assassination, Iwas in fifth grade for THAT; but you young sprouts
were probably not around then ...
Regards,
Patrick R. Briggs
Dept. of Physics
The Citadel
Charleston, SC 29409
briggsp@citadel.edu
call disclaimer(joke,dashed_lines)
------------------------------
Date: 4 Feb 93 21:31:24 GMT
From: Steinn Sigurdsson <steinly@topaz.ucsc.edu>
Subject: Space Grown Semiconductors
Newsgroups: sci.space,sci.materials
In article <1993Feb3.231051.1@stsci.edu> gawne@stsci.edu writes:
In article <STEINLY.93Feb3183518@topaz.ucsc.edu>,
steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes:
[refering to space grown semiconductors]
> See Nature, _360_ 293-294 26 Nov 1992 for a summary review + references
OK, I tried that and discovered what I suspect most others will. The
Nov 92 issues are currently "at the bindry" for binding. Lovely.
I can't get anything that was published between July 92 and Dec 92
it would seem.
So, Steinn, if you have a spare few minutes might you post a brief
review of what the Nature article had to say?
Darn, I don't suppose Henry feels like making amends for the
frightful shortage of AvWe summaries recently...
Now, the actual sci.mat post was mainly concerned with
semi-conductor fabrication? The article focuses on protein
synthesis.
Basically, they say it has been hit&miss so far, some crystals
grow better, some worse. Some that grow better have since been
improved on Earth by using different techniques, no crystals
that wouldn't form at all on Earth have yet been formed in space.
For those that have been grown well in space only, none have yet had
a structure determined!? Basically they say that the best thing to
do is to spend a lot of time in orbit doing a lot of experiments
with someone on the spot to massage them along and that there may
never be a magic rush of new crystal formation + concominant structure
solutions... but they do think some crystals will only be successfully
grown in micro-g and may make it worthwhile.
BTW looks like there's now a journal decdicated to the issue,
"Journal of Applied Microgravity Technology" - might be a good
reference source. Journal of Crystal Growth also looks like
they deal with it a lot, specifically volumes 76 and 110
looks like they might be micro-g specials...
| 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: Thu, 4 Feb 1993 22:04:41 GMT
From: David E Turner <deturner@IASTATE.EDU>
Subject: Units and Star Trek
Newsgroups: sci.space
My understanding is that velocity is equal to c*warp^3 in the original
Star Trek and c*warp^5 in Star Trek: The Next Generation.
------------------------------
Date: Thu, 4 Feb 1993 22:05:00 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: Using off-the-shelf-components
Newsgroups: sci.space
In article <1993Jan27.190735.17499@cc.ic.ac.uk> atae@crab.ph.ic (Ata Etemadi) writes:
>... I just wondered what other components might be
>out there which are standard and space-qualified. I don't imagine
>for one minute that these components will be chosen for major space
>missions since they are just not expensive enough. Maybe the UOSAT
>folks will be willing to give them go...
It depends on who you ask. NASA is pretty fussy. Others aren't.
In practice, "space qualified" often means "it's been tried in space
and it works". The UoSAT people have been heard to complain that as
soon as they fly something once, the price zooms because the vendor
now thinks it's "space qualified" and therefore worth a lot more.
--
C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology
effect since OS/360. | henry@zoo.toronto.edu utzoo!henry
------------------------------
End of Space Digest Volume 16 : Issue 136
------------------------------