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1993-07-13
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Date: Fri, 13 Nov 92 05:00:04
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V15 #417
To: Space Digest Readers
Precedence: bulk
Space Digest Fri, 13 Nov 92 Volume 15 : Issue 417
Today's Topics:
ALTERNATIVE Heavy Element Creation in Universe
gloves in space
Japanese 1990 Lunar Probe
Lunar "colony" reality check (4 msgs)
Lunar "colony" reality check and Apollo fire
NASA Coverup
Pioneer 6 Update - 11/11/92 (3 msgs)
Reality check (2)
Space Digest V15 #412
Space Digest V15 #415
Space Propulsion Research
Space suit research?
Water and Moon Rocks?
Where are Pioneer and Voyager Headed?
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: Thu, 12 Nov 92 15:02:46 GMT
From: Dave Jones <dj@ekcolor.ssd.kodak.com>
Subject: ALTERNATIVE Heavy Element Creation in Universe
Newsgroups: sci.space
mcelwre@cnsvax.uwec.edu wrote:
> BIOLOGICAL ALCHEMY
>
>
> A very simple experiment can demonstrate (PROVE) the
> FACT of "BIOLOGICAL TRANSMUTATIONS" (reactions like Mg + O
> --> Ca, Si + C --> Ca, K + H --> Ca, N2 --> CO, etc.), as
>
>
This is well-known, and follows from research described in the 50s by an
associate of John W. Campbell, Jr., in which an avian source of auric
metal ovoids proved to involve SIMULTANEOUS fusion of low MW elements which
provided the driving energy for Fe + I -> Au.
Note that this experiment ALSO involved the results of sprouting beans.
--
||Dave Jones (dj@ekcolor.ssd.kodak.com)|Eastman Kodak Co. Rochester, NY |
------------------------------
Date: Thu, 12 Nov 92 11:08:09 PST
From: rborden@ra.UVic.CA (Ross Borden)
Subject: gloves in space
>In article <Bx9tw3.EzH.1@cs.cmu.edu| rborden@ra.UVic.CA (Ross Borden) writes:
>| A better idea might be to cast a glove from heat shrink plastic.
>|It would be just large enough for an astronaut to fit his hand into.
>|The cuff of the glove would have a seal to attach it to the sleave of his
>|suit. After fitting it on, he would gently heat the glove to form it to
>|his hand.
>| It should provide a few atmospheres, enough to prevent damage.
^^^
>One atmosphere is all we need.
Brain was not in gear before keyboard was engaged :-) Obviously,
that should be PSI, not atmospheres. We don't actually need a full atm.
for the gloves, since the suits themselves are only about 5 PSI. Three
in the gloves should be enough to minimize the pressure differential
between suit and gloves.
>--
>Bruce Watson (wats@scicom) Tumbra, Zorkovick; Sparkula zoom krackadomando.
>------------------------------
_______________________________________________________________________________
| .sig? I don't need no stinking .sig! |
| rborden@ra.uvic.ca |
-------------------------------------------------------------------------------
------------------------------
Date: 12 Nov 92 14:47:18 GMT
From: Curtis Roelle <roelle@uars_mag.jhuapl.edu>
Subject: Japanese 1990 Lunar Probe
Newsgroups: sci.space
baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes:
>In article <BxKFIA.5Er.1@cs.cmu.edu>, 0004244402@mcimail.com (Karl Dishaw) writes...
>>I saw a UPI dispatch saying that Japan launched two satellites to the
>>Moon in January 1990, but there wasn't anything in the FAQ about them.
>>Does anybody know what happened on that mission and whether they got
>>any useful data?
>>
Regarding useful data. As I recall it was an engineering mission more
than a science mission.
>I wrote this about the Japan probes a year and a half ago. I've also
>appended Yoshiro Yamada's post on a later lunar fly.
> HITEN STATUS REPORT
> March 8, 1991
> Japan's small Moon probe, Hiten, made its seventh lunar flyby on March 3,
>passing about 13,300 km from the Moon. JPL's Deep Space Network is tracking
>the spacecraft. On February 28, the 34 meter Goldstone antenna supported
>ranging tests on Hiten, and were successful. On March 1, the same antenna was
>used to collect 24 minutes of ranging and doppler data.
> Hiten was launched into Earth orbit on January 24, 1990. The spacecraft
>was then known as MUSES-A, but was renamed to Hiten once in orbit. The 430 lb
>probe looped out from Earth and made its first lunary flyby on March 19, where
>it dropped off its 26 lb midget satellite, Hagoromo. Japan at this point
>became the third nation to orbit a satellite around the Moon, joining the
>Unites States and USSR.
> The smaller spacecraft, Hagoromo, will remain in orbit around the Moon.
>An apparently broken transistor radio caused the Japanese space scientists to
>lose track of it. Hagoromo's rocket motor fired on schedule on March 19, but
>the spacecraft's tracking transmitter failed immediately. The rocket firing
>of Hagoromo was optically confirmed using the Schmidt camera (105-cm, F3.1) at
>the Kiso Observatory in Japan.
Although the photograph confirmed firing of the rocket for lunar orbit
insertion, there is no direct evidence proving that Hagoromo entered
lunar orbit, or that it still remains in lunar orbit. This is
according to Robert Farquhar and David Dunham, who were both with
NASA-Goddard at the time. Radio contact with Hagoromo was never
regained, and the spacecraft is too small to be observed visually from
Earth. Hagoromo is "assumed" to be in lunar orbit, but the fact
that the transmitter failed when the rocket was fired raises some
doubt.
> Hiten will continue to make lunar flybys on a regular basis, typically
>once a month. According to Takahiro Yamada at ISAS, Hiten will be performing
>aerobreaking experiments on March 19 and 30. These experiments will be done
>using the atmosphere of the Earth. The next lunar flyby is scheduled for
>April 26.
[Hitten Ephemeris, and Yohiro Yamada's post -- deleted]
Japan has a second spacecraft that is busy making swingbys of the Earth
and moon. The Geotail spacecraft has made two passes of the moon, with
several more planned. Even-numbered lunar encounters are passages on the
moon's leading edge which removes orbital energy from the spacecraft.
Odd-numbered lunar encounters are passages on the trailing edge which cause
Geotail to gain energy. Last week Geotail came back home for a perigee
passage at Earth. Here is Geotail's schedule over the next couple months,
from information provided by David Dunham:
GEOTAIL ENCOUNTERS:
NOV 5 Perigee
8 Lunar #3
Dec 10 Apogee
Jan 10 Lunar #4
12 Perigee
Curt Roelle
roelle@sigi.jhuapl.edu
------------------------------
Date: Thu, 12 Nov 1992 14:50:44 GMT
From: "John D. Boggs" <jboggs@umaxc.weeg.uiowa.edu>
Subject: Lunar "colony" reality check
Newsgroups: sci.space,alt.sci.planetary
From article <1drh9aINN91n@gap.caltech.edu>, by carl@SOL1.GPS.CALTECH.EDU (Carl J Lydick):
> In article <1992Nov11.143433.18514@news.weeg.uiowa.edu>, jboggs@umaxc.weeg.uiowa.edu (John D. Boggs) writes:
> =>
> =
> =Yes to blindness in newborns, but it is the *nitrogen* that has the narcotic
> =effect in deep sea diving -- hence the use of helium for the really really
> =deep dives.
>
> If oxygen at high pressures DIDN'T cause the bad effects, why bother mixing it
> with helium? Yes, nitrogen has narcotic effects at high pressure, but so does
> oxygen.
> --------------------------------------------------------------------------------
Well, I'm not saying it doesn't have bad effects, I'm saying it doesn't have
*narcotic* effects. However, it's been pointed out to me via e-mail that
oxygen does indeed have narcotic effects as well as the nasy poison kill-you
effects at high pressure.
I guess we just got incomplete information in my dive classes. Or maybe
it's just that at sport diving depths nitrogen narcosis is much more likely
to set in that any narcotic effects of oxygen. Live & learn.
-John D. Boggs uunet!erato!jdb
------------------------------
Date: Thu, 12 Nov 1992 14:31:19 GMT
From: Andrew Hamilton-Wright <andrew@mks.com>
Subject: Lunar "colony" reality check
Newsgroups: sci.space,alt.sci.planetary
In article <BxKJ3t.Dux@acsu.buffalo.edu> v071pzp4@ubvmsb.cc.buffalo.edu (Craig L. Cole) writes:
>I'm no expert at deep sea diving or anything, but don't they use the helium
>to increase to total atmospheric pressure in their submerisibles? So that
>the pressure inside and outside the craft are more equal?
>
>This is the opposite of space -- these guys are trying keep there craft
>from imploding due to pressure. Increasing the pressure inside the craft
>reduces the loads on the craft's strucutre.
True, and the mix gas at very high pressures is He to avoid Nitrogen
Narcosis (intoxification - Leads to one of my Favourites : Martini's
Law - Sixty feet down = 1 Martini)
But this brings up another point I have always wondered about: Does
the sudden decompression of the capsule during ascent (The previously
mentioned drop in pressure from near atmospheric to the .3 atm mentioned)
cause any (temporary) medical effects similar to the 'bends' found in
diving when returning from a high pressure environment to a low?
These effects are driven by the presure ratios involved.
(Said effects would include temporary numbness, shortness of breath,
(which I am sure occurs anyway) and possible pain in the joints)
-andrew
--
/|| // // ,'/""\' Andrew Hamilton-Wright andrew@mks.com (519)884-2251
/ ||/// //\' `\\\ Database(Admin), Mortice Kern Systems Inc.
/ |/ /_// \\___/ 56 Scottsdale, Guelph,Ont.
o/ "Everything is possible except skiing through a revolving door"
------------------------------
Date: 12 Nov 92 16:11:58 GMT
From: Doug Mohney <sysmgr@king.eng.umd.edu>
Subject: Lunar "colony" reality check
Newsgroups: sci.space,alt.sci.planetary
In article <1992Nov12.045803.1096@ke4zv.uucp>, gary@ke4zv.uucp (Gary Coffman) writes:
>The inverse square law is a hard master. A microwave array on the Moon
>needs a gain 1,000,000 times that of an array at LEO to produce the same
>beam on Earth's surface. A Lunar array needs to be 100 times larger than
>an array at GEO and is available only 12 hours a day to any given site on
>Earth, and receives solar power only 2 weeks a month.
Wellllll, yes and no.
You build more than one array. Build a bunch of them, since some are going to
get wiped out by incoming garbage at some point in time :) Real estate is
cheap.
There's also some tricks you can do with the beam which you can't do with an
SPS, but I don't have the references or the SEI guy here to remember exactly
what you can do.
> It would take decades
>of concentrated work to build a Lunar array after permanent manned presence
>is established on the Moon, if the array is to be constructed from native
>materials.
Decades? You've been sipping from Szabo's cup, I see. :) The metals for
rectennas (?) are easy enough to cook up and stamp/mold/whatever.
Play in the intelluctual sandbox of Usenet
-- > SYSMGR@CADLAB.ENG.UMD.EDU < --
------------------------------
Date: Thu, 12 Nov 1992 00:02:19 GMT
From: Josh 'K' Hopkins <jbh55289@uxa.cso.uiuc.edu>
Subject: Lunar "colony" reality check
Newsgroups: sci.space,alt.sci.planetary
carl@SOL1.GPS.CALTECH.EDU (Carl J Lydick) writes:
>Power produced on the lunar surface and beamed directly to earth would have a
>number of drawbacks:
> 1) You'd need a very tight beam, which you'd have to be able to aim.
This is supposedly possible if you have very large antennas, something that is
much easier on the Moon than in orbit.
> 2) Even if you manage to take care of 1), the energy would be
> available at any particular place on Earth only 12 hours out of the
> day, with efficiency of the microwave link going down toward the
> ends of the period.
Which is a good reason to use interconnected power networks.
> 3) Any particular lunar installation will be inoperative for half of
> every lunar month, with decreasing efficiencies toward either end
> of the period in which it's operational.
True, but if you can build one you can build two. Alternatively you can do
interesting things with polar stations. However, I suspect that it would just be
easier to have multiple stations.
Mind you, I'm not saying lunar power is a great idea, but most of the technical
difficulties can be worked around.
--
Josh Hopkins jbh55289@uxa.cso.uiuc.edu
The only thing worse than writing a program that is constantly crashing on user
errors is remembering that you're the only one who uses the program.
------------------------------
Date: Thu, 12 Nov 1992 14:43:00 GMT
From: soc1070@CRABAPPLE.SRV.CS.CMU.EDU
Subject: Lunar "colony" reality check and Apollo fire
Newsgroups: sci.space,alt.sci.planetary
In article <1992Nov11.225129.28676@gn.ecn.purdue.edu>, mechalas@gn.ecn.purdue.edu (John P. Mechalas) writes...
>In article <11NOV199215071378@vx.cis.umn.edu> soc1070 writes:
>>
>>I'll concede this one. Re-reading the section of _Carrying The Fire_,
>>the actual cause of death is not explectly stated. However, death by
>>burns is implied. The text makes it sound as though the entire inside
>>of the capsule was consumed by fire. Probably sells more books that way.
>
>I have not heard of that book. Who was the author? If you are interested,
>check out Mike Gray's _Angle of Attack_. It's a history of the Apollo
>program, centering on the engineering aspects of the missions. Fascinating
>stuff.
>
>--
>John Mechalas "I'm not an actor, but
>mechalas@gn.ecn.purdue.edu I play one on TV."
>Aero Engineering, Purdue University #include disclaimer.h
_Carrying The Fire_ was written by Michael Collens (CM pilot on Apollo 11).
Its sort of a autobiography of his life as a test pilot then astronaut.
Great book, really well written.
------
Tim Harincar Millions long for immortality
Central Minnesota who don't know what to do with
Association of Rocketry themselves on a rainy Sunday
soc1070@vx.cis.umn.edu afternoon. -Susan Ertz
------------------------------
Date: 12 Nov 92 14:51:46 GMT
From: Henry Troup <hwt@bcarh11a.BNR.CA>
Subject: NASA Coverup
Newsgroups: sci.physics,sci.space
In article <1992Nov4.092243.1@fnalo.fnal.gov>, higgins@fnalo.fnal.gov
(Bill Higgins-- Beam Jockey) writes:
|>Hidden assumption: this film is playing back on your TV set at the
|>same speed it was photographed. (Or is it video?) In any case, you
|>need to know the correct frame rate to get an accurate value for t, and
Is there video of (Al Shepherd's?) golf shot in the moon? Apollo 15?
(senility strikes early - accumulated hypoxia effects:-) It seems to me
that that would be analysable for gravity, as the effect of the
horizontal impulse would give a confirming time scale. Or the astronaut
regularly hits three mile tee shots.
Henry Troup - H.Troup@BNR.CA (Canada) - BNR owns but does not share my opinions
"It's a good thing we don't get all the government we pay for."
------------------------------
Date: Thu, 12 Nov 1992 14:43:47 GMT
From: "John D. Boggs" <jboggs@umaxc.weeg.uiowa.edu>
Subject: Pioneer 6 Update - 11/11/92
Newsgroups: sci.space,sci.astro
From article <1992Nov11.170839.20313@elroy.jpl.nasa.gov>, by baalke@kelvin.jpl.nasa.gov (Ron Baalke):
>
> Pioneer 6 was launched on December 16, 1965 and is the oldest surviving
> spacecraft. Pioneer 6 was last supported on December 16, 1990, on the
> 25th anniversary of its launch, and no problems were encountered then.
Where is Pioneer 6 now? Is that the one that passed Pluto's orbit some
time back? How far has it gotten? [I'm out of touch with space stuff
since I gave up sci-fi]
-John D. Boggs uunet!erato!jdb
------------------------------
Date: 13 Nov 92 00:47:42 GMT
From: Ron Baalke <baalke@kelvin.jpl.nasa.gov>
Subject: Pioneer 6 Update - 11/11/92
Newsgroups: sci.space,sci.astro
In article <1992Nov12.144347.5579@news.weeg.uiowa.edu>, jboggs@umaxc.weeg.uiowa.edu (John D. Boggs) writes...
>From article <1992Nov11.170839.20313@elroy.jpl.nasa.gov>, by baalke@kelvin.jpl.nasa.gov (Ron Baalke):
>>
>> Pioneer 6 was launched on December 16, 1965 and is the oldest surviving
>> spacecraft. Pioneer 6 was last supported on December 16, 1990, on the
>> 25th anniversary of its launch, and no problems were encountered then.
>
>Where is Pioneer 6 now? Is that the one that passed Pluto's orbit some
>time back? How far has it gotten? [I'm out of touch with space stuff
>since I gave up sci-fi]
>
Pioneer 6 is in solar orbit in the inner part of the solar system. Four
spacecraft were launched in the 1960's to study the Sun, Pioneer 6, 7, 8 and
9. All but Pioneer 9 are still alive. Here are the orbital elements for
Pioneer 6.
Each entry is as follows:
MISS indicates the mission name, followed by its launch date in the
form of an L followed by YYMMDD. The last number on this line is
a U followed by YYMMDD, which indicates when the database was updated.
EPOCH = First number is epoch of elements as YYMMDD. HHMMSS.
Second number is start time, third number is stop time for elements.
Start and stop times given as YYMMDD.FF (i.e. FF is fraction of a day).
X = Classical elements in Earth ecliptic and equinox of 1950.
First line gives, left to right: semimajor axis (km), eccentricity,
inclination (degrees).
Second line gives, left to right: longitude of ascending node
(degrees), argument of periapsis (degrees), mean anomaly.
All elements are Sun-centered.
________
MISS PIONEER 6 L651216 U850304
EPOCH = 651216. 000000. 651216.00 731218.00
X = 134387958.00000 94.2805931000e-03 .16916329000000
-101.49333000000 4.5929197000000 -3422.7628000000
EPOCH = 731218. 000000. 731218.00 820101.00
X = 134367314.34489 94.2609224339e-03 .20239761376389
-109.09551548849 12.226221186036 -38.025874630285
EPOCH = 820101. 000000. 820101.00 830101.00
X = 134425840.00000 94.4089691000e-03 .16864667000000
-102.58174600000 5.4331765000000 119.68898000000
EPOCH = 830101. 000000. 830101.00 850101.00
X = 134443580.00000 94.3645660000e-03 .16903797300000
-102.57813800000 5.4968432700000 -178.04414400000
EPOCH = 841101. 000000. 850101.00 991231.00
X = 134453616.99108 94.2278871396e-03 .16897494141936
-102.62726688528 5.4036423943013 -122.93463008118
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Give people a second
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | chance, but not a third.
|_____|/ |_|/ |_____|/ |
------------------------------
Date: 12 Nov 92 16:56:19 GMT
From: Randy Jordan <jordan@warped.pnl.gov>
Subject: Pioneer 6 Update - 11/11/92
Newsgroups: sci.space,sci.astro
In article <1992Nov11.170839.20313@elroy.jpl.nasa.gov>, baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes:
|>Xref: pnl-oracle sci.space:15125 sci.astro:11423
|>Path: pnl-oracle!ogicse!uwm.edu!zaphod.mps.ohio-state.edu!swrinde!sdd.hp.com!elroy.jpl.nasa.gov!kelvin.jpl.nasa.gov!baalke
|>From: baalke@kelvin.jpl.nasa.gov (Ron Baalke)
|>Newsgroups: sci.space,sci.astro
|>Subject: Pioneer 6 Update - 11/11/92
|>Keywords: Pioneer 6
|>Message-ID: <1992Nov11.170839.20313@elroy.jpl.nasa.gov>
|>Date: Wed, 11 Nov 92 17:08:36 PST
|>Article-I.D.: elroy.1992Nov11.170839.20313
|>Sender: news@elroy.jpl.nasa.gov (Usenet)
|>Reply-To: baalke@kelvin.jpl.nasa.gov
|>Organization: Jet Propulsion Laboratory
|>Lines: 21
|>News-Software: VAX/VMS VNEWS 1.3-4
|>Nntp-Posting-Host: kelvin.jpl.nasa.gov
|>
|>
|> PIONEER 6 STATUS REPORT
|> November 11, 1992
|>
|> Yesterday, the Deep Space Network's 70 meter antenna in Goldstone,
|>California supported a tracking pass of the Pioneer 6 spacecraft. Receiver
|>lock was attained, but we were unable to attain telemetry lock because no
|>subcarrier was detected. The expected bit rate was 16 bps uncoded telemetry.
|>The AGC (Automatic Gain Control) was initially at -175.3 dbm, but was seen to
|>fluctuate causing the receiver to toggle in and out-of-lock. The problem is
|>under investigation.
|>
|> Pioneer 6 was launched on December 16, 1965 and is the oldest surviving
|>spacecraft. Pioneer 6 was last supported on December 16, 1990, on the
|>25th anniversary of its launch, and no problems were encountered then.
|> ___ _____ ___
|> /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
|> | | | | __ \ /| | | | Jet Propulsion Lab |
|> ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Give people a second
|>/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | chance, but not a third.
|>|_____|/ |_|/ |_____|/ |
|>
--
Where is Pioneer 6 and how far away?
RJ
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
To Thyne Own Self be true...
myne opinions are.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
------------------------------
Date: Thu, 12 Nov 92 15:51:03 GMT
From: Doug Mohney <sysmgr@king.eng.umd.edu>
Subject: Reality check (2)
Newsgroups: sci.space
In article <BxKxDv.14u.1@cs.cmu.edu>, roberts@cmr.ncsl.nist.gov (John Roberts) writes:
[in reference to doing work on the moon...]
>I think a lot of the initial work could be done with robots, more cheaply than
>sending humans there right away. (Once we know more, and hopefully have more
>appropriate launchers, we can send humans.)
You'll need some humans hanging around, just to apply duct tape.
Play in the intelluctual sandbox of Usenet
-- > SYSMGR@CADLAB.ENG.UMD.EDU < --
------------------------------
Date: Thu, 12 Nov 92 08:59:06 EST
From: Bill Collins <GE777010@brownvm.brown.edu>
Subject: Space Digest V15 #412
Apollo 1 fire:
One of the main reasons that the fire was so devastating was the fact
that at the time Apollo capsules had 100% oxygen atmospheres at normal
atmospheric pressure (14.7 lbs./sq.inch). That's a lot of oxidizing
agent to help with combustion! After Apollo was allowed to fly subsequent
to the Apollo1 fire the pressure was dropped to 5.3 lbs/sq. inch (am I
right, Henry?).
Bill
------------------------------
Date: Thu, 12 Nov 1992 09:19 EST
From: "Howie McCausland (802)388-3711x5754" <HOWIE%MIDD.BITNET@mitvma.mit.edu>
Subject: Space Digest V15 #415
I have been puzzled while reading the discussions of the anticipated close
encounter with comet Switf-Tuttle in 2126. While various posters have specu-
lated about schemes to deflect the comet's path should it look like an actual
collision was imminent, nobody has addressed the really interesting possibil-
ity: Let's be daring, and try to aim the sucker into a trajectory that per-
mits aerocapture into an earth orbit!
Now, I suppose one contemplating such an attempt would have to ask oneself,
"Do you feel LUCKY today?", but it makes for an interesting thought experiment
at least. The aerocapture itself shure would be one hell of a show for
people underneath!
How possible would this be? Does the mass, velocity, etc. of the comet allow
sufficient energy to be dissapated in the atmosphere to permit capture?
What would likely environmental effects be? What mass of useful volatiles
could thus be delivered to earth orbit? What impact would outgassing from
the orbiting comet nucleus have on near-earth space activities? Inquiring
minds want to know.
Hell, if we're going to speculate about 2126, let's be imaginative!
Howie McCausland
Middlebury College
------------------------------
Date: Thu, 12 Nov 1992 05:05:44 EST
From: William Fabanich <WAF102@psuvm.psu.edu>
Subject: Space Propulsion Research
Newsgroups: sci.space
What universities are best knownfor their research into space propulsion
research ? How about a list, a ranking, and/or general opinions ? Whatever you
might feel answers this question best.
Thanx,
Bill Fabanich
waf102@psuvm.psu.edu
------------------------------
Date: Thu, 12 Nov 1992 14:00:12 GMT
From: "Michael K. Heney" <mheney@access.digex.com>
Subject: Space suit research?
Newsgroups: sci.space
In article <BxL47u.6Fs.1@cs.cmu.edu> roberts@cmr.ncsl.nist.gov (John Roberts) writes:
>
>In the NASA Select coverage of a Shuttle mission (this year, I think) in which
>EVAs were used, I believe the commentator remarked that with something other
>than the usual pre-EVA cabin depressurization, only about half an hour of
>EVA pre-breathe was required. I considered that to be an astounding
>statement, but I never heard any followup. (I'm pretty sure that the mission
>was STS-49, and the cabin pressure was 10.2 psi.)
I remember that, too - I recall that the Shuttle cabin pressure was reduced
to 8.4 (?) psi, which gretly reduced the pre-breathe times. Given the
number of EVA's they had to do on that flight (Intelsat rescue), this
was a Very Good Thing.
--
Mike Heney | Senior Systems Analyst and | Reach for the
mheney@access.digex.com | Space Activist / Entrepreneur | Stars, eh?
Kensington, MD (near DC) | * Will Work for Money * |
------------------------------
Date: 12 Nov 92 14:44:33 GMT
From: Dave Jones <dj@ekcolor.ssd.kodak.com>
Subject: Water and Moon Rocks?
Newsgroups: sci.space
Bruce Hendler (bruceh@mothra.rose.hp.com) wrote:
>
> The other evening I was watching a PBS special about the moon. I briefly
> caught a portion of the program about some scientists creating water
> from moon rocks brought back by one of the Apollo missions. It was being
> done by introducing hydrogen into the rock. They showed this working...
> you could see water dripping from the moon rock. Could someone please
> explain this in more detail. Like I said, I only caught a glimpse of it and it
> totally amazed me.
>
> Thanks in advance...
>
This is not a particularly big deal. Water, being hydrogen oxide, can
be formed from hydrogen and any source of oxygen. There was a recent
posting to the effect that some elements in moonrock are in a relatively
high oxidation state, so it's no surprise that you get some kind of reaction
with hydrogen under mild conditions. If you really up the temperature you can
extract almost all the oxygen from minerals using hydrogen, except for
the part locked up in silicates. The result is metal (useful), water
(if you don't throw it away as steam) and slag.
Since water is a valuable commodity on the moon, but hydrogen is scarce,
there's interest in taking hydrogen there and using it to make the
water for bases. Since hydrogen represents only 11% of the mass of
the equivalent of water, it makes sense to ship that instead. The only
question was, how easy is the trick? The answer seems to be: pretty easy.
--
||Dave Jones (dj@ekcolor.ssd.kodak.com)|Eastman Kodak Co. Rochester, NY |
------------------------------
Date: Thu, 12 Nov 1992 16:41:25 GMT
From: Nick Haines <nickh@CS.CMU.EDU>
Subject: Where are Pioneer and Voyager Headed?
Newsgroups: sci.space
In article <1992Nov11.225206.7968@samba.oit.unc.edu>
cecil@physics.unc.edu (Gerald Cecil) writes this table:
The Starflight Handbook, p.6 quotes figures from
Cesarone, Sergeyevsky, and Kerridge, ``Prospects for the
Voyager Extra-Planetary and Interstellar Mission'', JBIS 37
(March 1984), 99-116. Anyone have this handy?
The Starflight book gives the following table:
Pioneer 10 Pioneer 11 Voyager 1 Voyager 2
Loss of Signal 1994/59 AU 1996/45 AU 2012/121 AU 2013/106 AU
Departure Vel
Asymptotic (AU/yr) 2.4 2.2 3.5 3.4
Trajectory angle
to Earth Orbit plane 2.9 12.6 35.5 -47.5
(degs)
Closest stellar 3.27 1.65 1.64 0.80
approach (ly)
Star Ross 248 AC +79 3888 AC +79 3888 Sirius
yrs to reach 32,600 42,200 40,300 497,0000
The Pioneer 11 & Voyager 1 trajectories look quite different, but they are
both going in the general direction of AC +79... whose name gives the Dec
at least.
I did some back-of-envelope figures on these, and something's wrong
with them. To 2sf, these are the distances of P-11 and V-1 from the
sun at their respective closest approaches to AC +79 3888):
Pioneer 11: 1.5
Voyager 1 : 2.2
In order to obtain these, of course I've had to assume that the probes
will be travelling at a constant velocity equal to their asymptotic
velocity. This should be a good approximation (the sun's influence at
these distances being tiny). Having got these figures, we can
calculate a number for the distance to the various stars, by
Pythagoras. AC +79 3888 must be sqrt (1.5^2 + 1.65^2) = 2.23 ly from
the sun, according to the Pioneer figures, and sqrt (2.2^2 + 1.64^2) =
2.74 ly from the sun according the the Voyager figures. Not only are
these numbers very different from each other, they're also much less
than the correct distance to AC +79 3888.
Doing the same calculation for Ross 248 gets us a distance of 3.5 ly
(correct figure is 10.3), and for Sirius 26.8 ly (correct figure is
8.7 ly).
So am I going wrong or are these figures just nonsensical?
(back-calculating from the distances to Ross 248 and Sirius gives me
`yrs to reach' of 268,000 and 170,000 respectively).
Nick Haines nickh@cmu.edu
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End of Space Digest Volume 15 : Issue 417
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