Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V11_5/V11_542.ZIP/V11_542

Internet Message Format | 1991-07-08 | 17KB

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson
Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/[e-mail] (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests)
          ID </afs/andrew.cmu.edu/usr1/ota/Mailbox/UaTkbFO00VcJ8URE4C>;
          Wed, 20 Jun 1990 01:29:53 -0400 (EDT)
Message-ID: <[e-mail]>
Precedence: junk
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Wed, 20 Jun 1990 01:29:15 -0400 (EDT)
Subject: SPACE Digest V11 #542

SPACE Digest                                     Volume 11 : Issue 542

Today's Topics:
            Nebula light emission
            Model Rockets in Orbit
              Magellan Update - 06/19/90
               Re: "KH-12" and LACROSSE
              Re:  HST amateur projects
            Re: Galileo Update - 06/14/90
          Re: NASA Data access on Internet?
       Lenoir monthly press meeting set for June 20 (Forwarded)
         Re: Aim For The Moon - model rocket contest
        Animation of Weather Satellite Photos
          Re: DSN Reliability and Resources Question

Administrivia:

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

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

From: [e-mail]
Date: Tue, 19 Jun 90 11:04:56 EDT
Subject: Nebula light emission


>Mark Maxwell asked about flouresence from nebula


    Actually, some nebulae are seen by reflected light, but the ones you are
    referring to glow by flouresence.  This is when short wavelength light
    is absorbed and then re-emitted at a longer wavelength.  Recall the
    so-called "black light posters" or the misnamed "neon" colors popular in
    fashion. The source of the short wavelength light is the embedded
    stars.  See such astronomy texts as the one by Abell, or Pasachoff and
    Kutner.


Mike Monce
Physics Dept
Connecticut College

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

Date: 19 Jun 90 13:57:00 PDT
From: "1st Lt. Henry S. Cobb" <[e-mail]>
Subject: Model Rockets in Orbit
To: "space+" <[e-mail]>


Five years ago, the MIT Aero/Astro Engineering department had something
going called Project Goddard.  The aim was to be the first non-governmental
organization to orbit a payload.  First stage was solid.  Second and third
stages (as I recall) were kerosine/LOX.  They got as far as burning up a
10-lb thrust prototype third stage engine on a test stand before I left.

The goal was to put 1 kilogram in orbit.  We learned a lot, especially that
things like guidance systems do not shrink nearly as easily as fuel tanks.
I don't know if the project is still going; in any case, the goal has been
achieved by the first launch of Pegasus, which was (more or less) a private
launch vehicle.

The SCOUT Planning Guide says that a Scout booster (21500 kg GLOW) can put
a 250 kg payload into a 200 Km orbit, which is about as low as you can get
and still call it an orbit.  Linear scaling says that an 86 kg model rocket
could put 1 kg into the same orbit.  Unfortunately, the scaling ain't
linear!

Scout is about as simple a rocket as you can get.  The stages are all solid
fuel, more or less the same as high-class model rocket engines.  The
guidance system is incredibly simple: a roll-yaw stabilization gyro, a
pitch stabilization gyro, and a timer.  The timer kicks the pitch gyro
occasionally to bend the trajectory downrange.  Even though it's 1960
technology, you're not going to build a system much lighter than that
with microprocessors.  The fourth (and optional fifth) stages are spun up
pointing in the right direction, but otherwise unguided.

Anyone who's seriously considering building a simple solid-fuel rocket
should take a look at the Scout.  To make a significantly smaller rocket,
you have to be able to significantly improve on that design.  It won't
be easy.

Not a Scout lover, just a skeptic -- Stu
(cobbhs @ afsd-ssd.af.mil)

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

Date: 19 Jun 90 22:55:50 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Magellan Update - 06/19/90


                     MAGELLAN STATUS REPORT
                          June 19, 1990

     The Magellan spacecraft continues to cruise and perform
nominally 51 days prior to encounter with Venus. Six of the seven
daily star calibrations were fully successful last week in spite
of increased solar activity. The average daily attitude update
was 0.05 degrees.

     The foreground/background filter successfully rejected
several spurious interrupts on June 9 and 10, and aided the star
scanner unit to pick up the correct star pairs both days.

     The week was capped with a very successful test of the
personnel, the software and the command sequences required to
recover the random access memory safing within 10 hours of orbit
insertion. The breadboard test showed recovery from its
intentional safing configuration and successful orbit insertion.

     The spacecraft is now 113 million miles from Earth and has
closed to within less than 10 million miles from Venus. Its
heliocentric velocity is more than 80,000 miles per hour. One way
light time, as of Monday, was 10 minutes and nine seconds.

     SPACECRAFT
     Distance from Earth (mi)             113,888,559

     Velocity Heliocentric                80,630 mph

     One-way light time (6/18/90)         10 mins, 9 secs

       _   _____    _
      | | |  __ \  | |       Ron Baalke           |  [e-mail]
      | | | |__) | | |       Jet Propulsion Lab   |  [e-mail]
   ___| | |  ___/  | |___    M/S 301-355          |
  |_____/ |_|      |_____|   Pasadena, CA 91109   |

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

Date: 18 Jun 90 10:03:32 GMT
From: mcsun!ukc!icdoc!syma![e-mail]  (Nick Watkins)
Subject: Re: "KH-12" and LACROSSE

From article <[e-mail]>, by [e-mail] (Dragon Taunter):

>>>A while ago NASA and the Pentagon said one of the spy
>>>satellites (it sounded like KH-12) had not deployed
>>>properly from a shuttle and parts were supposed to
> I have read that the KH designations are no longer used and that the actual
> codename for the satellite was LACROSS or something like that.  I am under
> the impression that the USAF knew the satellite was lost so they intentionally
> blew it incase any parts of it should fall into the USSR.  Thus explaining
> they breakup into four peices.
According to Jeffrey Richelson's excellent new book, "America's Secret Eyes
In Space", the KH designations are no longer used, & so the new imaging
satellites are called Advanced KENNAN (KENNAN was the KH11). LACROSSE
however is a large radar satellite, and thus an equine of a different
hue entirely.
 Best book yet on imaging spysats, I'd say, & essential reading for all
contributors to this thread. Widely available in US, found mine in a San
Diego mall.
 As to what happened to the last 2 Shuttle launches of KH type
satellites, who knows? Not I.

Nick
--
Dr. Nick Watkins, Space & Plasma Physics Group, School of Mathematical
& Physical Sciences, Univ. of Sussex, Brighton, E.Sussex, BN1 9QH, ENGLAND
JANET: [e-mail]   BITNET: [e-mail]

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

Date: 18 Jun 90 15:50:36 GMT
From: mcsun!ukc!icdoc!mvax.cc.ic.ac.uk!sunc![e-mail]  (D.A.G. Gillies Supvsr Dr K.J. Bignell)
Subject: Re:  HST amateur projects

In article <[e-mail]> [e-mail] (Arnold G. Gill) writes:
>In article <[e-mail]>, [e-mail]
>(D.A.G. Gillies   Supvsr  Dr K.J. Bignell) says:
>>
>>In article <[e-mail]>
>>[e-mail]
>>(Ranjan S Muttiah) writes:
>>>How far into the edges of the universe can HST point ?
>> According to a NASA scientist writing in Scientific  American,about
>>14 000 million light years,or roughly 90% of the way to the big bang.
>     Isn't this a little bit misleading?  Given an object that is bright
>enough, one should be able to see it all the way back to the Big Bang (even if
>it has been red-shifted away).  I guess it is a little difficult to explain to
>the public that it is not how far you can see with HST that is important, but
>rather how faint and with what resolution.  In fact, in astronomy, asking how
>far is almost meaningless - it depends on far too many theories/assumptions.

 When asked how far HST could point,I replied with the figure I had heard
quoted.The response to your follow up is simple - no you can't see all the
way to the Big Bang,because until 100 000 years after the Big Bang matter and
radiation were coupled,and the universe was opaque.It wasn't until things
were cool enough for *atoms* (rather than nuclei) to form that photons could
decouple from the matter to give a transparent universe.Even if this were not
true,red shift is pretty significant.HST is NOT a radio telescope,so if all the
radiation you are detecting is downshifted beyond near-infrared,it's not much
use.
 I repeat - should there be QSO's or proto-galaxies at distances out to
14 billion ly,then HST should have a good chance of finding them.

            David Gillies ([e-mail])

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

Date: 19 Jun 90 06:59:22 GMT
From: mtndew![e-mail]  (Stephen J. Friedl)
Subject: Re: Galileo Update - 06/14/90

>      The AC/DC bus imbalance measurements have remained very stable.  The AC
> measurement continues to indicate a near short circuit to chassis.

How can the spacecraft function with its AC power supply nearly
shorted to ground?  Why is it not disabled entirely?  Am I missing
something, or is this A Big Deal?

     Steve

--
Stephen J. Friedl, KA8CMY / Software Consultant / Tustin, CA / 3B2-kind-of-guy
[phone]  / [e-mail]  / {uunet,attmail}!mtndew!friedl

Sat-is-fac-tion (sat' is fak" shen) n.   Seeing Pick Systems cave into UNIX

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

Date: 14 Jun 90 21:32:26 GMT
From: dev!dftsrv!amarna.gsfc.nasa.gov![e-mail]  (John 'Fast-Eddie' McMahon)
Subject: Re: NASA Data access on Internet?

In article <[e-mail]>, [e-mail] (Thomas F. Smith) writes...
:In the article it says "...anyone with access to the Internet,
:BITNET, or Telenet computer network can call NSSDC computers
:arount the clock.  Callers can review a menu of services and

(Mucho general information deleted)

:Their you have it.  The capability exists.  Those who know how
:to do it must be the ones who have a "real" need for the data!
:
:So HOW?
:
:Anybody willing to provide the info?

The SPAN (Space Physics Analysis Network) Management Office is part of
the National Space Science Data Center (NSSDC), they can probably assist you in
accessing the menu systems.

Contact:    [e-mail]

Keep in mind that these systems are primarily for legitimate research projects,
not casual browsing.  Please contact them only if you plan on doing research.

------------------------------------------------------------------------------
John "Fast Eddie" McMahon                        [e-mail]
Code 930.4 - Advanced Data Flow Technology Office      SDCDCL::FASTEDDY (SPAN)
NASA Goddard Space Flight Center in Greenbelt, MD               [phone]
------------------------------------------------------------------------------
Disclaimer:  These are my views.  Although I am a NASA contractor, I do not
             speak for NASA or ST Systems Corporation.  I don't work for
             Jim Green, the National Space Science Data Center, or any of it's
             support organizations.

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

Date: 19 Jun 90 18:24:14 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Lenoir monthly press meeting set for June 20 (Forwarded)

Mark Hess                                          June 18, 1990
Headquarters, Washington, D.C.
(Phone:  [phone])


EDITORS NOTE:  N90-45

LENOIR MONTHLY PRESS MEETING SET FOR JUNE 20


     NASA Associate Administrator for Space Flight Dr. William B.
Lenoir will hold his monthly review with the news media on
Wednesday, June 20, from 3 until 5 p.m. EDT.  The review will be
held in Room 425, Building 10-B, 600 Independence Ave., S.W.,
Washington, D.C.

     Space Shuttle Director Robert L. Crippen and Space Station
Freedom Director Richard H. Kohrs also may participate in the
review.

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

Date: 19 Jun 90 18:36:28 GMT
From: sam.cs.cmu.edu![e-mail]  (Vincent Cate)
Subject: Re: Aim For The Moon - model rocket contest


If you send $2.00 to:

Aerotech, Inc
1955 South Palm St,  Suite 15
Los Vegas, NV 89104

  you can get a catalog of large engines.  They at least go
up to "M" and maybe "N".  Aerotech's phone numbers are [phone]
and [phone].  An "M" sells for $995.  A "G" sells for $17
at a local store.  I do not have a catalog yet, but it seems prices
are going to be doing something like:

A
B
C       $1
D       $2
E       $4
F       $8
G      $16
H      $32
I      $64
J     $128
K     $256
L     $512
M    $1024
N    $2048

The above estimated prices are probably not too far off for "G" and up.
There is some place that sells them for 30% off.

In case you did not already know, each letter has twice the newton-seconds
of the previous one.  A "G" has about 120 N-S of thrust and the fuel
weighs about 60 grams (I don't know the case weight).  While "A" to "D"
are rather small, there are large rocket motors for sale for reasonable
prices.  Note that if you had one stage for each of the above motors
your total motor cost would be about $4,096.  Your delta-V should be
more than enough to get escape velocity if your payload is about the
weight of an "A".   Note that the transmitter may transmit a high
powered burst for a very short time, say 1/100 of second every 100
seconds, so as not to use very much power.  With a 90 foot dish on the
ground we should be able to pick up such a signal.  I think us little
guys could really make rockets to send things into space!!!!!!!!!!!


It seems you may have to be a member of Tripoli before you can buy
large engines (at least from some places).  Tripoli's address is:

Tripoli Rocketry Association Inc.
P.O. Box 87669
San Diego, CA  92138-7669


The important point is that a small rocket gets the same delta-V for
the same payload/fuel ratio of a large rocket if it has the same Isp
and these "little" rockets have about the same Isp.  This means that
ROCKETS SCALE DOWN VERY WELL except for air resistance and control.
If all you want to do is go up, control may not be much of a problem
(could fins and spinning be enough?).  Getting into orbit would be
hard since you would need good control.  The higher you get the less
of a problem air resistance will be.  Smaller rockets do have smaller
diameters, but air resistance does cause lower payload/fuel ratios for
small rockets getting the same delta-V as larger ones.

   -- Vince

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

Date: 15 Jun 90 16:47:41 GMT
From: [e-mail]  (James R. White)
Subject: Animation of Weather Satellite Photos


Does anybody know of any software that will display a series of GIF
files in rapid succession that runs on the MAC?  It would be useful
for animating the weather satellite photos.

--
 James R. (Bob) White            ||  [e-mail]
 Los Alamos National Laboratory  ||  Phone [phone] (Work)
 N-6 / MS K559                   ||  Phone [phone] (Home)
 Los Alamos, NM  87544  USA      ||  FTS 843-3853

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

Date: 18 Jun 90 17:11:04 GMT
From: mcsun!ukc!icdoc!syma![e-mail]  (Nick Watkins)
Subject: Re: DSN Reliability and Resources Question

From article <[e-mail]>, by [e-mail] (Mark SOKOLOWSKI):
> In article <[e-mail]> [e-mail] (Dieter Kreuer) writes:
>>
>>How much did ESA get for delivering the first SPACELAB module
>>to NASA? I'll never understand why they gave it away for free (it
>>was worth $1 billion, as far as I remember).
> Spacelab was given away free.
I think we (ESA) agreed to deliver the first set of hardware & NASA were to pay
for any further sets. I also seem to recall they actually did buy one,
am I right ?
 I think ESA's motivation was a leg up into manned Space Technology,
plus the early 1970's shuttle traffic model which anticipated rather a
lot (900 in 10 years ?) more Shuttle flights than we have seen,
necessitating more than one set of hardware.

Nick
--
Dr. Nick Watkins, Space & Plasma Physics Group, School of Mathematical
& Physical Sciences, Univ. of Sussex, Brighton, E.Sussex, BN1 9QH, ENGLAND
JANET: [e-mail]   BITNET: [e-mail]

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

End of SPACE Digest V11 #542
*******************