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Space Digest Fri, 30 Jul 93 Volume 16 : Issue 948
Today's Topics:
<None> (2 msgs)
DC-X/Delta Clipper qustion. (2 msgs)
DC-X Prophets and associated problems
Did our CCD catch a high orbiting satellite or a near-Earth asteroid?
FTL communication?
Happy B-day NASA!
Questions on SETI? (2 msgs)
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, 30 Jul 1993 06:06:08 GMT
From: nsmca@ACAD3.ALASKA.EDU
Subject: <None>
Newsgroups: sci.space
Legal Question:
Could Canada have a space lottery, and can US citizens buy tickets, or charge
for tickets. And if a USA citezen wins, can they then go benefit of the
Canadian Company (the sponsor of the lottery, especially if its a MIR)..
Or would it be "Illegal"??..
If the US is too backwards to have a space lottery, then space can go to
canada, russian, europe or wherever..
===
Ghost Wheel - nsmca@acad3.alaska.edu
------------------------------
Date: 30 Jul 1993 08:31:49 GMT
From: Josh Hopkins <jbh55289@uxa.cso.uiuc.edu>
Subject: <None>
Newsgroups: sci.space
nsmca@aurora.alaska.edu writes:
>Legal Question:
>Could Canada have a space lottery, and can US citizens buy tickets, or charge
>for tickets. And if a USA citezen wins, can they then go benefit of the
>Canadian Company (the sponsor of the lottery, especially if its a MIR)..
>Or would it be "Illegal"??..
There aren't likely to be rules against what you are talking about. Lotteries
for Mir rides are not inherently illegal (as some may have inferred). However,
if you intend to hold a lottery you should talk to a lawyer and clear up all
the details. Lotteries tend to be heavily regulated, at least in the US.
--
Josh Hopkins jbh55289@uxa.cso.uiuc.edu
"Physics is like sex: sure, it may give some practical results,
but that's not why we do it."
-R. Feynman
------------------------------
Date: Fri, 30 Jul 1993 03:53:26 GMT
From: Tommy Nordgren <f85-tno@nada.kth.se>
Subject: DC-X/Delta Clipper qustion.
Newsgroups: sci.space
I have noticed that the basic layot of the DC-X/Delta Clipper design
layout is very similar to the several resuable plug nozzle designs
suggested in the sixties.
Will the Delta Clipper be a full plug nozzle design -
that is will the center of the base be extruded into a truncated cone,
that will be an important part of the force transfer from the rocket exhaust
gasses to the vehicle.
--
-------------------------------------------------------------------------
Tommy Nordgren "What is a woman that you forsake her
Royal Institute of Technology and the hearth fire,
Stockholm and the home acre,
f85-tno@nada.kth.se to go with the old grey widow maker."
--------------------------------------------------------------------------
------------------------------
Date: 30 Jul 1993 05:50:16 GMT
From: Josh Hopkins <jbh55289@uxa.cso.uiuc.edu>
Subject: DC-X/Delta Clipper qustion.
Newsgroups: sci.space
f85-tno@nada.kth.se (Tommy Nordgren) writes:
>I have noticed that the basic layot of the DC-X/Delta Clipper design
>layout is very similar to the several resuable plug nozzle designs
>suggested in the sixties.
> Will the Delta Clipper be a full plug nozzle design -
>that is will the center of the base be extruded into a truncated cone,
>that will be an important part of the force transfer from the rocket exhaust
>gasses to the vehicle.
When McDonnell Douglas produced its first plans in Phase I of the program the
Delta Clipper was to have been powered by an aerospike or aeroplug. They
quickly changed to standard rocket engines. I believe the current plan includes
eight engines, four "boosters" and four "sustainers." They are identical
except for the fact that the sustainers would have variable geometry engine
bells, thus giving them better performance at high altitudes. The booster
engines would shut down at a lower altitude.
Aerospike/aeroplug engines do seem to be usefull, but to my knowledge no one
has a flight-ready design. Rocketdyne did test both standard and linear
aerospike engines on test stands but they don't produce them. Part of the
reason aeroplug engines were considered for SSTO rockets is that they simplify
thermal protection for rear-first entry. For the Delta Clipper, which is
a more demanding nose-first entry design, the thermal heating takes place on
the nose so a rugged behind doesn't help as much.
--
Josh Hopkins jbh55289@uxa.cso.uiuc.edu
"Physics is like sex: sure, it may give some practical results,
but that's not why we do it."
-R. Feynman
------------------------------
Date: 29 Jul 1993 19:45:15 -0400
From: Matthew DeLuca <matthew@oit.gatech.edu>
Subject: DC-X Prophets and associated problems
Newsgroups: sci.space
In article <238dfp$sh5@access.digex.net> prb@access.digex.net (Pat) writes:
>Why is NASA with all it's budget problems funding NASP.
>200 Million dollars last FY. it's cancelled now, but
>why were they not averse to Pour Money into a program
>that had no physical chance of success, while not
>even giving TOKEN funding to a highly possible program
>like DC-X.
NASP is hardly an impossible project. Very difficult, sure, but not
impossible.
Besides, even if it *is* impossible, how do you determine that before you
put some money into it and do some research?
--
Matthew DeLuca
Georgia Institute of Technology "Never fight a land war in Asia."
Office of Information Technology
matthew@prism.gatech.edu - MacArthur
------------------------------
Date: 29 Jul 93 19:30:49 GMT
From: Bruce Watson <wats@scicom.AlphaCDC.COM>
Subject: Did our CCD catch a high orbiting satellite or a near-Earth asteroid?
Newsgroups: sci.astro,sci.space
In article <CAw8I2.H6q@news.cis.umn.edu| bryj0001@student.tc.umn.edu (Claia O Bryja-2) writes:
|a 30-inch telescope and a CCD just east of Minneapolis/St. Paul, our camera
|snapped the motion trail of something interesting. The exposure time was 15
|seconds, and the trail extended about 100 arcsec. Going at that rate, if it
|were a satellite in a circular orbit, it would have a period of about 50 or
|60 hours. This seems a bit long. How many satellites orbit that far out?
|The direction of the streak was close to north-south, and we were pointing
|fairly close to zenith, so this satellite would have to be in a polar orbit
|also (our latitude is 45 N).
Your object may have been one of the Soviet Prognoz satellites launched
from 1972 to 1978 into very eccentric orbits (~500 x 200,000 km)
with an inclination of 65 degrees. Five of the seven launched are
thought to be in orbit, but the elements are not known. Email me
more details.
--
Bruce Watson (wats@scicom.alphaCDC.COM)
------------------------------
Date: 29 Jul 93 17:34:47 GMT
From: "Theodore F. Vaida ][" <tfv0@ns1.cc.lehigh.edu>
Subject: FTL communication?
Newsgroups: sci.space
In article <CAwK3G.6qp@sugar.NeoSoft.COM>, mmarolda@NeoSoft.com (Mike Marolda) writes:
>In article <WCHAYWARD.52.743906897@CHEMISTRY.watstar.uwaterloo.ca> WCHAYWARD@CHEMISTRY.watstar.uwaterloo.ca (Colby Hayward) writes:
>> Here's a nutty little concept that was posted on a sci-fi newsgroup
>>(somewhere in the rec.arts.startrek region, I think).
>> What if you had an ideal rod (ie. massless, uncompressable,
>>unbendable) that was one lightyear long, suspended in space. You have two
>>observers, one at each end (A and B). So we have:
>> A ---------------------<one lightyear>------------------- B
>> So, what happens when the observer at A grabs the rod and pulls it
>>towards him/her? Wouldn't the end at B move also? At the same time?
>>If no, why not?
>> Its got me puzzled.
>I believe the fastest the "signal" would travel would be at the speed of sound
>for the material that rod is made of.
>Mike Marolda
>mmarolda@sugar.neosoft.com
If the rod was ideal, massless and uncompressable/strainable (ie:
undefined Young's modulus (infinte stress/zero strain)) then the
rod would travel at end B at the speed it was pulled at end A. If the
material had ANY elasticity (streachability) then it would stretch and
the 'signal' would travel at the speed of sound for that material...
you see the speed of sound for the above ideal material (undefined Y)
is infinite! Unless somone with a mat.sci degree knows better (I get
this from 'Structures: Why things Dont Fall Down').
--
---------==============Sig file cover sheet=====================---------
->POLAR CAPS<- or tfv0@lehigh.edu
Pages including this page: 1
-----
"One must not confuse John Donne's famous quote `No man is an Island' with
New York Telephone's `We're all connected'" - Dad
------------------------------
Date: 30 Jul 1993 06:18:45 GMT
From: George William Herbert <gwh@soda.berkeley.edu>
Subject: Happy B-day NASA!
Newsgroups: sci.space
In article <29JUL199316203508@juliet.caltech.edu> irwin@juliet.caltech.edu (Horowitz, Irwin Kenneth) writes:
>According to a blurb today on CNN, today is the 35th anniversary of the signing
>of the National Aeronautics and Space Act by President Eisenhower, which led
>to the creation of NASA.
Eeek! I was born on the same day NASA was founded, and didn't know all
these years???
I'm not quite sure what to think, except that I hope I get flamed less
when I'm 35 ;-)
-george william herbert
Retro Aerospace
(I still have a year to fly an orbital payload before I turn 25, though.
Wish me luck 8-)
------------------------------
Date: 30 Jul 93 07:35:15 GMT
From: "S.H." <sr600uab@sdcc16.ucsd.edu>
Subject: Questions on SETI?
Newsgroups: sci.space,sci.math
On my last post:
> Impossible.
>
> Else, tell them to try to figure out how to detect the London whether
^^^^^^^
> first with only marginary certainty requirements. Consider to fix
> their own problems first.
>
Either substitute " whether" for "weather", or take them to be the same...
un_cer...
H.S. | " He continued walking further, down, without looking back, without
| worrying he would ever find a way to get back. He didn't care -
| only wished he might meet a rain on the way - whether it was a
| happy rain, or a sad rain..."
( ranwk.t_6/1992. La Jolla, SanDiego )
------------------------------
Date: 30 Jul 93 06:20:35 GMT
From: "S.H." <sr600uab@sdcc16.ucsd.edu>
Subject: Questions on SETI?
Newsgroups: sci.space
In article <1993Jul29.085057.10570@lut.ac.uk> N.A.Stennett@lut.ac.uk (NA Stennett) writes:
>
> I have a couple of questions about the SETI program and I was wondering
>whether anybody out there on the net could enlighten me.
> Firstly given the equipment that is being used, how far away would
>somebody using such equipment be able to detect intelligent life on earth?
>I am assuming that the source signal would have been transmitted for a
>sufficent length of time to reach the receiver.
Even it did reached the receiver, it would not be certain that
the receiver would understand the messages.
" Everybody sees the picture. Does everybody know what it means ? "
> Secondly, I seem to recall a posting on the net which talked about
>a coded message that was either transmitted from Arecibo(sp?) or included
>on one of the Voyager or Pioneer probes. However this message was given to
>a team of "experts" to decode and unfortunately they failed! (I have probably
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
I see. Is this also true? -:)
A Term of "experts" was also given orders to "encode" messages also.
>got the facts completely wrong so prehaps somebody could put me straight).
No. You were right. They had failed.
>If this is the case then how do we propose to detect incoming signals with any
>degree of certainy.
Impossible.
Else, tell them to try to figure out how to detect the London whether
first with only marginary certainty requirements. Consider to fix
their own problems first.
>Is it that we could detect the signals quite easily by
>measuring the power levels at certain frequencies and if they are continually
>above the background levels or varying in a consistent manner then we can
>conclude that they must be from a unnatural source.
This could be true. The sender simply has no control over the
tranmision line. Any noises siginal could possibly be added to
the source "above the backgroud level".
> However we would have great difficulty in trying to decode the signals?
Certainly. Unless if they can decode the noise at the same time.
>Finally, in after ten years the project has found nothing. What would
>we be able to deduce?
Nothing.
It takes an intel. to Read an intel.
>
>#=============================================================================#
># E-mail: N.A.Stennett@lut.ac.uk
Un_necessary.
------------------------------
End of Space Digest Volume 16 : Issue 948