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Date: Wed, 28 Oct 92 05:03:26
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V15 #352
To: Space Digest Readers
Precedence: bulk
Space Digest Wed, 28 Oct 92 Volume 15 : Issue 352
Today's Topics:
A career in the Space Program - or Forget It!?
Comet Collision
DataBase of all space flights a/v ?
HRMS for ETI
MET-4 VHRR
mystery lifting body craft depicted
Recognizing a Dyson sphere if you saw one
Slush Hydrogen question (2 msgs)
Smith-Tuttle Comet a threat to earth?
Two-Line Orbital Element Set: Space Shuttle
very small astro science sensors??
VIDEOTAPE OF OCT 9 FIREBALL
Welcome to the Space Digest!! Please send your messages to
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----------------------------------------------------------------------
Date: 27 Oct 92 19:59:42 GMT
From: Jack Romachek <romachek@golem.ucsd.edu>
Subject: A career in the Space Program - or Forget It!?
Newsgroups: sci.space
>> Should I try some new approach to job hunting in aerospace, or should
>> I totally concentrate on my other interest which is molecular biology?
>It all depends on you. If working in Aerospace is of such high intrinsic
>value to you, then you should push for it and nothing else, but ya got to
>be willing to go anywhere for it....
Sounds like a search for the Holy Grail...
>JPL may not be the best place to start
>off from....in fact anywhere in So Ca will be a waste....
JPL is the only place I have solid contacts. In fact, I was employed
on the Voyager Project before returning to finish my degree in San
Diego. I had expected return to JPL with the possibility of advancement,
but my friends are laying people off, and not hiring... I am told
that this is NASA-wide.
>Aerospace jobs
>are to be had, but in Georgia and Arizona.....
Could you be more specific, what's in Georgia and Arizona? Are they
immune from getting cut on the next round?
>Remember, it has to be of
>great importance to you....otherwise the grass will always seem greener
>when you look at other industries or professions....
There has to be better advice than this, like some solid facts on
available positions vs. number of applicants. My specialty is space
navigation and guidance, but if after three or four years of waiting
for a position to open and seeing continual layoffs and budget cuts,
then it becomes fairly clear that is not the way to go.
------------------------
romachek@golem.ucsd.edu
------------------------------
Date: Wed, 28 Oct 1992 04:06:32 GMT
From: "Richard A. Schumacher" <schumach@convex.com>
Subject: Comet Collision
Newsgroups: sci.space
>There is a greater change of dying from a train wreck or a car accident than
>getting plowed by the comet.
Agreed, since all of us will be dead anyway when P S/T returns. I still
maintain that any single, forseeable event which would kill all of humanity
deserves to be called a tremendous danger.
>Another thing to consider: How big is this comet? It doesn't have to hit
>us to do some major damage. YOOGE tidal waves, earthquakes, knocking
>the earth out of it's orbit, etc. Y'know...minor worldwide disaters.
No. It's a dirty iceball about 10 km wide at the most, so it masses
less than the island of Manhattan. If it doesn't actually hit the Earth,
the only effect will be one a hell of a spectacular show in space.
------------------------------
Date: Wed, 28 Oct 1992 09:05:16 GMT
From: Hartmut Frommert <phfrom@nyx.uni-konstanz.de>
Subject: DataBase of all space flights a/v ?
Newsgroups: sci.space
Hi,
Is there any comprehensive database on all spaceflights/launches/projects
a/v, including name, launch date/time, payload, orbit, etc, from the
beginning in 1957, for use on PC ? (Best PD or cheapware, optimal via ftp)
Thanx for any pointer.
--
Hartmut Frommert <phfrom@nyx.uni-konstanz.de>
Dept of Physics, Univ of Constance, P.O.Box 55 60, D-W-7750 Konstanz, Germany
-- Eat whale killers, not whales --
------------------------------
Date: 28 Oct 1992 03:38:57 GMT
From: "David M. Palmer" <palmer@cco.caltech.edu>
Subject: HRMS for ETI
Newsgroups: sci.space,sci.bio
nickh@CS.CMU.EDU (Nick Haines) tried to write:
> [... stuff, including reference, about how life probably emerged here ...]
> My guess for P(life evolving | suitable planet) is 1e-12.
One way to estimate P(life | suitable planet), while adjusting for the
weak local anthropic principal ("how strange that we should be on
a planet which has life---NOT!" :-)) is to look at how long it took life to
evolve, and compare that to the length of the 'window of opportunity'
in whch life like ours could have started--not so early that the
Earth got resterilized by continued planetery bombardment and not
so late that there is no time to develop Usenet before the Sun
becomes inhospitable.
It turns out that life occurred just about as soon as the Earth was
tolerable, like within 100 million years (this number is approximate, I
don't know offhand the actual number. Nobody does.) (This leads to
speculation that life may have developed one or more times earlier as
well, but was wiped out each time when the next planetesimal was
accreted.) This is very near the start of the window, which is roughly
5 billion years long as a rough number.
This is compatible with a P(life | suitable planet) ~ 1. If P(life |
suitable planet) were small, then on those planets which did, against
the odds, develop life, there would be no preference for the beginning
of the window rather than the end, and much preference for the big, wide
middle.
However, until about 600 Million years ago, life didn't seem to do
much evolving, (from a fossil-viewing, anthropocentric, politically
incorrect dead-white-European-male viewpoint :-)). If the Cambrian
explosion (see this Month's Scientific American for a report on this)
had been delayed by a factor of three (which is nothing in terms of
astrophysics and the statistics of small numbers) brains might
not have evolved before old Mr. Sun decided to stretch out a bit
and eat the inner planets, a few billion years from now. (Sorry
about the tenses in the last sentence. I don't know how to
conjugate English verbs in the combined contrafactual subjunctive
past-factual future tense, if that is indeed the tense I should have used.)
This suggests that P(brains | life) is not close to 1, and so
life does not imply that brains (or even creatures more complex than
a jellyfish) will eventually arise.
However, P(brains) can be pretty low without making SETI hopeless.
--
David Palmer palmer@alumni.caltech.edu
------------------------------
Date: Mon, 26 Oct 1992 10:29:33 +0000
From: Andrew Haveland-Robinson <andy@osea.demon.co.uk>
Subject: MET-4 VHRR
Newsgroups: sci.space
In article <bertilg@epix.hks.se.2.0@bertilg> bertilg@epix.hks.se@bertilg writes:
>Hello,
>We are two computer engineers working on a project in reciveing weather
>sattelite pictures. Now we wonder if anyone has recieved high resolution
>pictures from MET-4 somwhere in Europe. We also want some advice on which
>reciever to use and software to use.
Can't help much, but you could try ftp from cumulus.met.ed.ac.uk
Change directory to "images". IR and visible images of Europe from
Meteosat, twice daily, in 1152 x 900 GIF format (size of Sun root window).
The subdirectory "gifs" has smaller 3x daily images of the Nordic areas,
the UK, and Europe.
Mail root@met.ed.ac.uk for further info.
Andy.
+-----------------------------------------------------------------------+
| Haveland-Robinson Associates | Email: andy@osea.demon.co.uk |
| 54 Greenfield Road, London | ahaveland@cix.compulink.co.uk |
| N15 5EP England. 081-800 1708 | Also: 0621-88756 081-802 4502 |
+-----------------------------------------------------------------------+
>>>> Those that can, use applications. Those that can't, write them! <<<<
------------------------------
Date: Wed, 28 Oct 1992 00:12:41 GMT
From: Dennis Newkirk <dennisn@ecs.comm.mot.com>
Subject: mystery lifting body craft depicted
Newsgroups: sci.space
In November's "Monitoring Times" (a magazine for radio hobbiests)
there is a 3 view drawing (page 43) from an anonymous source
of a small aircraft which the magazine links to the August 5
encounter of United flight 934 747 and a small fast wingless aircarft
over the California desert (recently reported in Av Week, etc..)
The magazine states that the sketch is of a vehicle tested recently
on a hypersonic sled test track at Holloman AFB, NM. The magazine
also repeats stories of a small fast wingless craft that were in
Av Week a couple months ago.
For those who can't find the magazine at their news stand, I will
attempt to describe the drawing: basic shape and size (judging from
canopy size) is very similar to the X24-B, but with an added curved
underside. Add to that large flaired chines (like an SR-71's) to the
nose and inward canted tail surfaces like the F-177 prototype.
Dennis Newkirk (dennisn@ecs.comm.mot.com)
Motorola Inc, Land Mobile Products Sector
Schaumburg, IL
------------------------------
Date: 28 Oct 92 00:49:43 GMT
From: Erik Max Francis <max@west.darkside.com>
Subject: Recognizing a Dyson sphere if you saw one
Newsgroups: sci.astro,sci.space
train@ccwf.cc.utexas.edu writes:
> I may be wrong about this, I forget the aprroximate size of a dwarf star and
> wouldn't be anything near the size of a dwarf star would it? I thought dwarf
> stars, at least white dwarfs, were about the size of the Earth.
"Dwarf" usually means main-sequence dwarf, which is the same class of
star that the Sun is. Main-sequence stars can be all sorts of sizes,
ranging from very large and massive O or B stars to very dim and cool M
stars. Our sun, a G2 V main-sequence star, is above average, though.
----------
Erik Max Francis Omnia quia sunt, lumina sunt. Coming soon: UNIVERSE _ | _
USmail: 1070 Oakmont Dr. #1 San Jose CA 95117 ICBM: 37 20 N 121 53 W _>|<_
UUCP: ..!apple!uuwest!max Usenet: max@west.darkside.com 464E4F5244 |
------------------------------
Date: Sun, 25 Oct 1992 23:54:44 GMT
From: Jeff Greason ~ <greason@ptdcs2.intel.com>
Subject: Slush Hydrogen question
Newsgroups: sci.space
If I can fit another technical question in between the election-year
propoganda...
I've been wondering about "slush" hydrogen ever since hearing about it
as part of the X-30(NASP) program. I had always thought it was partially
frozen hydrogen, in an attempt to get the volume for hydrogen tanks
down to a reasonable level.
However, I've been unable to find any information other than verbal
descriptions of it (no numbers), and my initial assumption about frozen
hydrogen doesn't seem to hold up, as my CRC says:
Density(liquid) 70.8g/l @-253 degrees C
Density(solid) 70.6g/l @-262 degrees C
Now it is certainly possible that the density increases as the
temperature continues to decrease, but I don't have that information.
Can someone explain this to me?
P.S. I still have received no information on the real drive source for
solar sails. Help!
Disclaimer: All opinions expressed are my own, and do not reflect the
position of Intel, Portland State University, or Zippy the Pinhead.
============================================================================
Jeff Greason "You lock the door ... And throw away the key.
<greason@ptdcs2.intel.com> There's someone in my head, but it's not me."
<jeffg@eecs.ee.pdx.edu> -- Pink Floyd
------------------------------
Date: 28 Oct 92 04:23:34 GMT
From: Josh 'K' Hopkins <jbh55289@uxa.cso.uiuc.edu>
Subject: Slush Hydrogen question
Newsgroups: sci.space
greason@ptdcs2.intel.com (Jeff Greason ~) writes:
>P.S. I still have received no information on the real drive source for
>solar sails. Help!
A solar sail is just a big sheet of reflective material. The "drive source"
is the sun - the sail is pushed by radiation pressure from light.
--
Josh Hopkins jbh55289@uxa.cso.uiuc.edu
"We can lick gravity, but the paperwork's a bit tougher." Wernher von Braun
------------------------------
Date: Wed, 28 Oct 1992 02:28:39 GMT
From: James Davis Nicoll <jdnicoll@watyew.uwaterloo.ca>
Subject: Smith-Tuttle Comet a threat to earth?
Newsgroups: sci.space
In article <mcdonald.443@aries.scs.uiuc.edu>, mcdonald@aries.scs.uiuc.edu (J. D. McDonald) writes...
>In article <STEINLY.92Oct26125854@topaz.ucsc.edu> steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes:
>
>
>>Speed relative to Earth is 50 km/s
>Lord Almighty! 1/6 the speed of light!!!!!! ???????
Hmmm. That would make a lightyear about 63 AU, Alpha
Centauri about 260 AU away, and light from the sun would take
about 5 days to reach Earth. Earth orbits at 0.6 'C', and I
*think* the sun should be a blackhole if C=50 km/s....
I think you're a tad low on the value of C.
------------------------------
Date: 28 Oct 92 06:22:45 GMT
From: TS Kelso <tkelso@afit.af.mil>
Subject: Two-Line Orbital Element Set: Space Shuttle
Newsgroups: sci.space
The most current orbital elements from the NORAD two-line element sets are
carried on the Celestial BBS, (513) 427-0674, and are updated daily (when
possible). Documentation and tracking software are also available on this
system. As a service to the satellite user community, the most current
elements for the current shuttle mission are provided below. The Celestial
BBS may be accessed 24 hours/day at 300, 1200, 2400, 4800, or 9600 bps using
8 data bits, 1 stop bit, no parity.
Element sets (also updated daily), shuttle elements, and some documentation
and software are also available via anonymous ftp from archive.afit.af.mil
(129.92.1.66) in the directory pub/space.
STS 52
1 22194U 92 70 A 92300.93750000 .00103280 00000-0 25599-3 0 127
2 22194 28.4623 88.9806 0006174 316.5369 265.3455 15.94356868 673
--
Dr TS Kelso Assistant Professor of Space Operations
tkelso@afit.af.mil Air Force Institute of Technology
------------------------------
Date: 27 Oct 92 16:57:45 GMT
From: Les Degroff <degroff@IntelliCorp.COM>
Subject: very small astro science sensors??
Newsgroups: sci.astro,sci.space
Day dreaming; thinking about writing a SF story I hit upon
an interesting "creative" problem which I would appreciate any
non proprietary ideas on.
What kind of measurements could be made by sensors or
systems of sensors that would fit through a 1 mm hole in 10 milliseconds.
(measurements must be completed in 10 milliseconds)
Is there any way one could expect to locate the probes location with
sensors of that size in that short of time. (assume the location is within
the local galactic cluster, and you can post process data as much as
needed.) Les DeGroff
(I may try to write this story if I can find or figure out some
plausible solutions to the technical problem)
------------------------------
Date: Wed, 28 Oct 1992 01:07:26 GMT
From: pbrown@uwovax.uwo.ca
Subject: VIDEOTAPE OF OCT 9 FIREBALL
Newsgroups: sci.astro,sci.space
For anyone out there who might have taken actual video of the Oct 9
fireball seen over the East Coast of the US at about 8 p.m. (or know
of someone who did) could you PLEASE send me an email note with that
information.
A group of interested meteor astronomers are tracking down all avaliable
video tapes of the event to determine an orbit for the object. At present
we have uncovered 17 seperate video tapings of the event from several
states. The fireball produced a meteorite which hit the trunk of a high
school student's car in Peekskill, New York. Though scientists were only
"loaned" the meteorite for a one week period (before the owner wanted it
back for the auction block) enough physical and chemical details of the
object were measured to make a decisive classification. The meteorite
turned out to be an L6 chondrite - a very common type. But, since there
is likely enough information out there (still largely hiding ;) ) to
determine an orbit the event is very unusual.
If your local station ran a locally shot video of the event on the night
of Oct 9 I would be very, very interested to get that information. If you
know of someone at a football game that night with a camcorder the odds
are pretty good they may have some valuable tape.
In any case please pass along any such information on the event.
Peter Brown
Dept. of Physics
University of Western Ontario
London, Ontario
N6A 3K7
Canada
peter@canlon.physics.uwo.ca
****************************************************************************
------------------------------
End of Space Digest Volume 15 : Issue 352
------------------------------