Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_0/V13_018.TXT

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Date: Mon,  7 Jan 1991 02:23:53 -0500 (EST)
Subject: SPACE Digest V13 #018

SPACE Digest                                      Volume 13 : Issue 18

Today's Topics:
               Re: Interstellar travel
            Re: Chiron and asteroid belts
             Re: * SpaceNews  31-Dec-90 *
           NASA Prediction Bulletin Format
        Re: Recent Newsstand Magazine Articles
           My last posting from this site (Philips)
   Re: Space Station Integrated Design Review completed (Forwarded)
          Re: Space News from Flight Int. for Dec90

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription requests,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

----------------------------------------------------------------------

Date: 31 Dec 90 18:29:24 GMT
From: hsdndev!frooz![e-mail]  (Steve Willner, OIR)
Subject: Re: Interstellar travel

From article <[e-mail]>, by [e-mail] (Henry Spencer):
> Setting aside the mythical "ramjet speed limit", there are two or three
> big, nasty problems with the Bussard ramjet:
> 1. Fusion of ordinary hydrogen is very slow
> 2. The inverse-square law demands humongous magnetic field intensities
> 3. Interstellar gas is not very ionized, and something might have to be
>     done to ionize it before you could get a useful grip on it with
>     a magnetic field, and doing that at reasonable energy cost is hard.

A useful rule of thumb is that interstellar matter is ionized at
densities lower than 1 hydrogen atom per cubic centimeter, neutral at
higher densities.  This density happens to be the average value for
interstellar space, but this average is made up of large regions of
lower density and small regions of (much) higher density.

You might have added:
4.  The Sun is located inside a large region of extremely low density:
something like 200 light years in radius with density less than 0.1 H
atom per cm^3.

> None of these is such an obvious derivative of the basic laws of physics
> that one can authoritatively state that there is no way around it, although
> number 1 is going to be a toughie.

The difficulties are enough that I wouldn't choose to spend my career
working on interstellar ramjet propulsion.
-------------------------------------------------------------------------
Steve Willner            Phone [phone]         Bitnet:   willner@cfa
Cambridge, MA 02138 USA                 Internet: [e-mail]

------------------------------

Date: 31 Dec 90 16:23:30 GMT
From: [e-mail]  (Heidi Hammel)
Subject: Re: Chiron and asteroid belts

David Tholen writes:

> | Henry Spencer writes:
> | > Mark Gellis writes:
> | > Also, does the existence of Chrion suggest that there might be
> | > large bodies like it in the cometary halo (most people think the
> | > average size of comets will be about 3-4 km., with the biggest ones
> | > being about 30-40 km.--I'm talking about the nucleus here, not the
> | > coma or the tail)?  Any ideas?
> | Seems a good possibility.  Last I heard, the dominant theory was that
> | Chiron is a dormant supercomet.  Triton and Pluto may well be the same sort
> | of thing on an even larger scale.
> Chiron is no longer dormant!  ..... [coma reported] ....
> Triton and Pluto, as well as all the other icy satellites of the outer planets
> have the potential for outgassing if they could be brought in closer to the
> Sun.  In fact, Pluto is probably losing some of its atmosphere due to Jeans
> escape, so one could argue that it is behaving something like a comet.

Triton is not dormant, either.  Voyager 2 images of Triton showed several
active plumes ejecting material into Triton's tenuous atmosphere.  The
precise mechanism driving the plume emission is still being hotly debated.
--
---      Heidi B. Hammel       ([e-mail])
--           "All the years combine, and melt into a dream ... "

------------------------------

Date: 31 Dec 90 18:39:53 GMT
From: idacrd![e-mail]  (Robert McGwier)
Subject: Re: * SpaceNews  31-Dec-90 *

From article <[e-mail]>, by [e-mail] (John Magliacane):
>
> * UoSAT NEWS *
> ==============
> of 9 microprocessors and 5000 kilobytes of RAM.  That's more computing
> power than had ever been launched by one rocket!
>
> UoSAT-3 (OSCAR-14) carries a 16-bit embedded microprocessor controller
> with 4.5 megabytes of RAM.  UoSAT-4 (OSCAR-15) carries the first
>

Its store and forward open access messaging system is now fully operational.

> UoSAT-4 (OSCAR-15) carries three microprocessors and a CCD Earth imaging
> camera.  Parallel processing available on the spacecraft will provide
>
This one carries nothing on since it failed shortly after launch.  It was
a grevious loss to UOS but a replacment is in preparation for launch in
1991 I believe.

>
> * ITALIAN MICROSAT *
> ====================
> Work continues in Italy on a new microsat amateur satellite.
> During the first week of December, the transmitter module, BCR module
>

We are indeed proud of our relationship with AMSAT-I in general but with
Alberto Zagni, I2KBD, and his crew in Milano.  They have taken Microsat
schematics, mechanical drawing, and without much help, have constructed
an operational Microsat.  So proud are we of them, that we have made his
group operators on PACSAT, the microsat run by AMSAT-NA.  A truly fine
new satellite building group is being formed in Milano and I am extremely
proud of them.


>
> * BADR-1 DECAYS *
> =================
> BADR-1, a Pakistani satellite launched by the People's Republic of China
>

Good riddance. This was a ripoff (err uhh I meant `copy') of UOSAT-2.
They insisted on operating the thing in the low end of 2 meters (in
the 2 meter EME band) and would never tell anyone anything.  This had
very very litte to do with amateur radio.  It was a terrible misuse
of amateur radio frequencies.  I happy the Pakistani's successfully
launched their first satellite but I am deeply distressed that it went
into service in the amateur radio bands and did not operate in the
amateur satellite service.

> John A. Magliacane


Thanks John for publishing this news.  It is a nice service.

Bob

--
____________________________________________________________________________
    My opinions are my own no matter    |    Robert W. McGwier, N4HY
    who I work for! ;-)            |    CCR, AMSAT, etc.
----------------------------------------------------------------------------

------------------------------

Date: 31 Dec 90 18:24:39 GMT
From: ncis.tis.llnl.gov!blackbird![e-mail]  (TS Kelso)
Subject: NASA Prediction Bulletin Format


As a service to the satellite user community, the following description
of the NASA Prediction Bulletin's two-line orbital element set format is
uploaded to sci.space on a monthly basis.  The most current orbital elements
from the NASA Prediction Bulletins are carried on the Celestial BBS, (513)
427-0674, and are updated several times weekly.  Documentation and tracking
software are also available on this system.  The Celestial BBS may be
accessed 24 hours/day at 300, 1200, or 2400 baud using 8 data bits, 1 stop
bit, no parity.

==============================================================================

Data for each satellite consists of three lines in the following format:

AAAAAAAAAAA
1 NNNNNU NNNNNAAA NNNNN.NNNNNNNN +.NNNNNNNN +NNNNN-N +NNNNN-N N NNNNN
2 NNNNN NNN.NNNN NNN.NNNN NNNNNNN NNN.NNNN NNN.NNNN NN.NNNNNNNNNNNNNN

Line 1 is a eleven-character name.

Lines 2 and 3 are the standard Two-Line Orbital Element Set Format identical
to that used by NASA and NORAD.  The format description is:

Line 2
Column     Description
 01-01     Line Number of Element Data
 03-07     Satellite Number
 10-11     International Designator (Last two digits of launch year)
 12-14     International Designator (Launch number of the year)
 15-17     International Designator (Piece of launch)
 19-20     Epoch Year (Last two digits of year)
 21-32     Epoch (Julian Day and fractional portion of the day)
 34-43     First Time Derivative of the Mean Motion
        or Ballistic Coefficient (Depending on ephemeris type)
 45-52     Second Time Derivative of Mean Motion (decimal point assumed;
           blank if N/A)
 54-61     BSTAR drag term if GP4 general perturbation theory was used.
           Otherwise, radiation pressure coefficient.  (Decimal point assumed)
 63-63     Ephemeris type
 65-68     Element number
 69-69     Check Sum (Modulo 10)
           (Letters, blanks, periods = 0; minus sign = 1; plus sign = 2)

Line 3
Column     Description
 01-01     Line Number of Element Data
 03-07     Satellite Number
 09-16     Inclination [Degrees]
 18-25     Right Ascension of the Ascending Node [Degrees]
 27-33     Eccentricity (decimal point assumed)
 35-42     Argument of Perigee [Degrees]
 44-51     Mean Anomaly [Degrees]
 53-63     Mean Motion [Revs per day]
 64-68     Revolution number at epoch [Revs]
 69-69     Check Sum (Modulo 10)

All other columns are blank or fixed.

Example:

NOAA 6
1 11416U          86 50.28438588 0.00000140           67960-4 0  5293
2 11416  98.5105  69.3305 0012788  63.2828 296.9658 14.24899292346978

Note that the International Designator fields are usually blank, as issued in
the NASA Prediction Bulletins.

--
Dr TS Kelso                           Assistant Professor of Space Operations
[e-mail]          Air Force Institute of Technology

------------------------------

Date: 30 Dec 90 17:56:19 GMT
From: van-bc!rsoft!mindlink![e-mail]  (Ed Meyer)
Subject: Re: Recent Newsstand Magazine Articles

> [e-mail] writes:
>
> Msg-ID: <[e-mail]>
> Posted: 30 Dec 90 23:39:42 GMT
>
> Org.  : University of Virginia
> Person: Laura Hayes Burchard
>
> While we're on the subject, I noticed in Time that the New York Times
> failed in its attempt to get the tapes of the Challenger's final moments
> released, with NASA arguing that the privacy of the astronauts' families
> demanded that they be kept secret.  I'm curious; have the families
> actually said this?  I recall that in the immediate aftermath, at least
> one family was attempting to get them released for use in a suit against
> NASA.
>    [ ... ]

Laura, I agree with your question.  If NASA doesn't have sworn statements from
families and/or authorized representatives then I don't know how they can make
specific claims.  On a more general scope, secrecy is usually the tip of an
"iceberg" associated with fear(s).  If so, wonder what the fear(s) may be.

------------------------------

Date: 31 Dec 90 17:13:29 GMT
From: agate!linus!philabs!briar![e-mail]  (Robert Casey)
Subject: My last posting from this site (Philips)

Goodbye.  Philips is having layoffs, and they did it at my site.  Only reason
that I haven't got told officially yet is that I'm out sick on disability (eye
trouble).  But several reliable sources tell me that I'm to be canned when I
return to work (Jan 2).  My normal remote dial-up computer access code no
longer works, I'm using a friend's code, at his house.  Don't think they can
tell whose.

The kind of work I did is television R&D, including HDTV (high defination TV,
regular NTSC television, developing patents (I have 11) in this field.  Also
have done DSP, & high speed digital logic design, up to 114MHz clock speeds.  I
posted my resume on misc.jobs.resumes  Or call me up and I'll mail anyone
interested a copy of it, and a list of my patents.  Will consider anywhere in
USA.  Corporations, and colleges (someone at a college called me about 2 weeks
ago, call again).
Also give my name and number to any and all headhunters.

Robert Casey            Amateur radio WA2ISE
855 Oradell Ave         Amateur radio packet:  WA2ISE@KD6TH
Oradell, NJ 07649
201-261-4066

Don't try to use e-mail, as Philips is going to delete my computer account the
day I get officially canned.  I don't expect to be able to log on again.

This is the dark side of American life.  But getting layed off is better than
getting killed in or near Tianamen Square.

------------------------------

Date: 31 Dec 90 14:40:41 GMT
From: eagle![e-mail]  (Ronald E. Graham)
Subject: Re: Space Station Integrated Design Review completed (Forwarded)

In article <[e-mail]>, [e-mail] (Nick Szabo) writes...

Based on Fred ISPDR report...

>>     The Integrated System Preliminary Design Review (ISPDR) for
>>the Freedom space station, a major milestone leading to the
>>construction, launch and assembly of the station, was completed
>>on schedule this week....

>Oh boy!  More blueprints!  More spreadsheets!  More CAD files!
>Who needs a space station when we can have more designs? Way to go
>NASA!!!

Such a demonstrated understanding of the Fred program.  Must have worked
on it for a while.

>>     "This was an outstanding effort," said Robert Moorehead,
>>Deputy Director for Space Station Freedom Program and
>>Operations.  "Not only did we accomplish the PDR on schedule, we
>>made the schedule despite having to devote a lot of time and
>>attention to other issues, like weight and power and EVA
>>(extravehicular activity) resources."

>Aw, shucks, who needs a space station with power and EVA anyway?
>Let's put aside these "other issues" and get back to painting
>pretty 3-D CAD pictures.  Who do you guys think you are, engineers?
>    :-) :-)

Yes.  What did you say you were again?
        :-) :-)

[blar, blar, blar...]

>>     "Certainly there will be design changes," said Moorehead,

>Certainly!  And certainly there will be NASA propaganda posted about
>how "outstanding" the design work is and whining about NASA not getting
>enough $billions from Congress.  Certainly we will see more pretty
>pictures in Av Week, and everybody will say "ooh" and "ahh", and
>nobody has to build a thing!  The money just keeps on coming in, and the
>more you screw up the more you get!  Wheeeee, what fun!!!    :-) :-)
>The Mir lottery isn't a scam.  *This* is a scam.

And, of course, you'd have had the darn thing up there by now.  :-) :-)

Follow-ups to alt.mouth.foam.  Happy holidays.

RG

------------------------------

Date: 31 Dec 90 18:12:36 GMT
From: zaphod.mps.ohio-state.edu!samsung!umich!sharkey!amara![e-mail]  (Tim McDaniel)
Subject: Re: Space News from Flight Int. for Dec90

[e-mail] (swaraj jeyasingh) writes:

   RSFSR's Ministry of Communications and Information Technology will
   pay R100 million ($176) ...

I heard that the Soviet Union's inflation was bad, but THAT bad?
568000 rubles per dollar?  8-)

(US$176 million would also be silly, though.  What's it a typo for?)

--
Tim McDaniel                 Applied Dynamics Int'l.; Ann Arbor, Michigan, USA
Work phone: [phone]                        Home phone: [phone]
Internet: [e-mail]                UUCP: {uunet,sharkey}!amara!mcdaniel

------------------------------

End of SPACE Digest V13 #018
*******************