Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_5/V11_547.TXT

Internet Message Format | 1991-07-08 | 15KB

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/QaU5jCa00VcJIWgU5F>;
          Thu, 21 Jun 1990 01:31:59 -0400 (EDT)
Message-ID: <[e-mail]>
Precedence: junk
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Thu, 21 Jun 1990 01:31:23 -0400 (EDT)
Subject: SPACE Digest V11 #547

SPACE Digest                                     Volume 11 : Issue 547

Today's Topics:
              Re: Model Rockets in Orbit
              Info from RISKS on Hubble
              Re: Model Rockets in Orbit
              Re: Saturn Rockets
               Re: Rockets to the moon
           Payload Status for 06/20/90 (Forwarded)
         NASA Headline News for 06/20/90 (Forwarded)

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]

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

Date: 20 Jun 90 13:01:38 GMT
From: mojo![e-mail]  (Doug Mohney)
Subject: Re: Model Rockets in Orbit

In article <Q~D$?[e-mail]>, [e-mail] (Michael V. Kent) writes:
>In response to 1st Lt. Henry S. Cobb, who writes about Project Goddard, MIT's
>attempt to perform the first private launch.  He writes, "...in any case, the
>goal has been achieved by the first launch of Pegasus...":
>
>Not to put down Pegasus -- it is an amazing accomplishment -- but I believe
>McDonnell Douglas beat OSC to orbit by a good seven months.

McDonnell-D was using a booster which was developed with government R&D money,
basically (correct me if I'm wrong). Pegasus was a more private venture, with
the government as a paying customer...

I suspect someone else will make a clear statement on the legalese of
a "private" launch.

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

Date:     Wed, 20 Jun 90 8:52:33 CDT
From: Will Martin <[e-mail]>
Subject:  Info from RISKS on Hubble

The following item was in the latest RISKS Digest; I scanned the recent
SPACE Digest traffic and did not find it posted there, so am sending a copy    to SPACE -- if it turns out to be a duplicate, my apologies...


RISKS-LIST: RISKS-FORUM Digest  Tuesday 19 June 1990   Volume 10 : Issue 10

Date: 19 Jun 90 03:09:36 CDT (Tue)
From: [e-mail] (Karl Lehenbauer)
Subject: More Space Telescope Problems

The June 18th issue of Aviation Week and Space Technology has a half-page
article on two problems the Hubble Space Telescope has been having.

One problem is that some RAM used by the fine guidance system is being
scrambled when the telescope passes through the South Atlantic Anomaly,
a region representing a "dip" in the Van Allen Belts that has been
known to be hazardous to spacecraft electronics for decades.  This happens
for a ten minute period during every 98-minute orbit.  The NASA deputy
project manager of the HST, Jean Olivier, said that they had evaluated
the radiation effects very carefully, but that they had apparently
miscalculated.

The data in the RAM is supplied, according to the article, by the
telescope's Rockwell Autonetics DF-224 general purpose computer.  The
magnetic core memory used by the Rockwell computer is not considered to
be susceptible to disruption by radiation.  Olivier said that the Rockwell
computer can be programmed to refresh the RAM ten times a second, with the
result being that a completely new set of parameters in the fine guidance
sensor electronics would be calculated every five seconds, thereby eliminating
the problem.

The second problem is with the telescope's solar arrays.  Analyses done in
Europe and the United States sugest that the poles that hold the solar
arrays in place, called bistems, bow under a 50F degree temperature gradient,
causing the ends of the arrays to move about ten inches, resulting in their
oscillating for up to six minutes.  Olivier said that the solution is to
program the spacecraft's magnetic torquers to apply counteracting forces.

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

Date: 20 Jun 90 16:12:48 GMT
From: usc!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Model Rockets in Orbit

In article <Q~D$?[e-mail]> [e-mail] (Michael V. Kent) writes:
>In response to 1st Lt. Henry S. Cobb, who writes about Project Goddard, MIT's
>attempt to perform the first private launch.  He writes, "...in any case, the
>goal has been achieved by the first launch of Pegasus...":
>
>Not to put down Pegasus -- it is an amazing accomplishment -- but I believe
>McDonnell Douglas beat OSC to orbit by a good seven months.

Only if you consider an ex-missile developed on government money to somehow
be a "private" launcher.
--
As a user I'll take speed over|     Henry Spencer at U of Toronto Zoology
features any day. -A.Tanenbaum| uunet!attcan!utzoo!henry [e-mail]

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

Date: 20 Jun 90 20:17:46 GMT
From: swrinde!cs.utexas.edu!milano!peyote![e-mail]  (Bob Mosley III)
Subject: Re: Saturn Rockets


...Henry's comments on the Saturn series of launch vehicles brings up two
questions:

1) We've seen the results of the Saturn program, but what about the progress
on the followup, the Nova series? I remember seeing photos of Werner Von Braun
standing beside small models of proposed Nova boosters, but these were from
1964 or so.

How far did development go on the Novas, and when did they officially get the
axe?

2) We've seen a great deal of text files appearing on here over the years. Is
there an archive site available for them? i'd be curious to see what's been
posted that I've missed....

                            OM

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

Date: 20 Jun 90 17:01:42 GMT
From: [e-mail]  (Lawrence Curcio)
Subject: Re: Rockets to the moon

Some detailed calculations, here.

Assumptions:

Rocket takes off from platform above significant air resistance

Gravity doesn't change much during burn time

Rocket is composed of class N clusters, because Class N engines
have the best mass ratios

Top stage is one N engine

Each stage carries stages above it that total half of the mass of
the current stage => mass ratio of each stage is 2.0

There is no payload or structural mass other than the engines
themselves.

So here's a BASIC program that does some quick calculations:

10 TB=3.78:REM BURN TIME
20 EV=7*5280:REM ESCAPE VELOCITY=7 MILES/SECOND
30 EV=EV*12*2.54/100:REM M/SEC
40 PRINT "ESCAPE VELOCITY=";EV
50 VE=211*9.8:REM EXHAUST VELOCITY=Isp*g
60 PRINT "Ve=";VE
70 N=4:REM MASS RATIO OF BARE N ENGINE
80 N=(4+2)/(1+2):REM MASS RATIO OF EACH STAGE
90 REM ASSUME ALL UPPER STAGES ARE 1/2 CURRENT STAGE MASS
100 PRINT "MASS RATIO EACH STAGE=";N
110 RV=VE*LOG(N)-9.8*TB:REM CORRECTED FOR GRAVITY
120 PRINT"VELOCITY INCREASE EACH STAGE=";RV
130 NSTAGE=INT(EV/RV +.999):REM ROUND UP
140 PRINT"MIN STAGES FROM 150K FEET";NSTAGE
150 NENG=3^(NSTAGE-1):REM WORK IT OUT
160 PRINT"ENGINES REQUIRED=";NENG
170 COST=NENG*1300
180 PRINT "MINIMUM COST IN $";COST

Output:

ESCAPE VELOCITY= 11265.41       (M/sec)
Ve= 2067.8                      (M/sec)
MASS RATIO EACH STAGE= 2
VELOCITY INCREASE EACH STAGE= 1396.246   (M/sec)
MIN STAGES FROM 150K FEET 9
ENGINES REQUIRED= 6561
MINIMUM COST IN $ 8529300   (That's $8,529,300.00)

Any calculational errors? Please correct and repost.


I don't think this is practical, but I AM ready for SOMETHING!
Larry Curcio (CMU)

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

Date: 21 Jun 90 03:07:23 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Payload Status for 06/20/90 (Forwarded)


    Daily Status/KSC Payload Management and Operations 06-20-90.


    - STS-35 ASTRO-1/BBXRT (at OPF) -

    The payload bay doors will be reopened today and experiment
    purge lines will be reconnected.


    - STS-37 GRO (at PHSF) -

    Propellant system leak checks will be performed today.


    - STS-40 SLS-1 (at O&C) -

    CITE interface testing continues.


    - STS-41 Ulysses (at ESA 60) -

    Ulysses systems test continues.  CITE MUE validation at the
    VPF and goal software verification at the O&C will be active
    today.


    - STS-42 IML-1 (at O&C) -

    Rack, floor, and module staging is continuing.


    - STS-45 Atlas-1 (at O&C) -

    Sepac installation will occur today.


    - STS-46 TSS-1 (at O&C) -

    Paper closure is active today.


    - STS-47 Spacelab-J (at O&C) -

    Rack 4 will be removed from the handling frame on first
    shift.  Rack 11 staging continues on second shift.

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

Date: 21 Jun 90 03:05:36 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 06/20/90 (Forwarded)

-----------------------------------------------------------------
Wednesday, June 20, 1990             Audio Service:  202/755-1788
-----------------------------------------------------------------

This is NASA Headline News FOr Wednesday, June 20.......


At the Kennedy Space Center Launch Pad 39-A yesterday, the
Auxiliary Power Units #1 and #2 were successfully hot fired on
the Space Shuttle Atlantis.  The Countdown Demonstration Test
with the STS-38 flight crew is scheduled for this Wednesday and
Thursday, June 20-21.  It will include a simulated engine firing
and cutoff at 11:00 A.M. on Thursday.  The official launch date
will be set at the Flight Readiness Review which is scheduled for
next week.

Meanwhile, at the Kennedy Space Center Orbiter Processing
Facility, preparations are underway to open the payload bay doors
of the Space Shuttle Columbia early next week to allow access to
the Astro-1 payload and the Broad Band X-Ray Telescope.  The 17-
inch disconnect valve on the external tank was removed and the
valve was shipped out to the vendor.  A new valve is being
installed.

In preparation for launch of the CRRES at Cape Canaveral in
Florida, the Atlas Centaur Rocket sucessfully completed the
Countdown Dress Rehearsal Test.  The spacecraft will be taken to
the launch pad next Tuesday.  The launch is scheduled for 4:50
P.M. EDT on July 9.
                            ********

The Magellan spacecraft continues to cruise and perform well.  It
is scheduled to encounter Venus in 50 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 spacecraft
is now 113 million miles from Earth and has closed to within less
than 10 million miles from Venus.  It is now traveling over
80,000 miles per hour.

                            ********

President Bush is scheduled to speak to NASA employees,
contractors and teachers attending an education seminar today
following his arrival at the Marshall Space Flight Center in
Huntsville, Alabama.  The President will participate in a
briefing on the Space Exploration Initiative and tour of the
Hubble Space Telescope facilities.  Coverage of the tour begins
at 3:00 P.M.  His live remarks will be on NASA Select TV at 3:30
P.M. EDT.








--------------------------------------------------------------
Here's the broadcast schedule for Public Affairs events on NASA
Select TV.  All times are Eastern.


Wednesday, June 20......

           3:00 P.M.          Coverage will begin of the
                              President's arrival at
                              the Marshall Space Flight Center.
           3:10 P.M.          The President participates in a
                              Question and Answer Session.
                              Highlights of his
                              tour of the Hubble
                              facilities will be included.
           3:30 P.M.          The President's live address.

           4:00 P.M.          X-29 Press Conference tape replay
                              at 12:45 P.M. at the Watergate.

Thursday, June 21

          10:00 A.M.          STS-38 Countdown Demonstration
                              Test.  The simulated liftoff will
                              begin at 11:00 A.M.

          11:30 A.M.          NASA Update will be transmitted.

Friday, June 22.........

          11:00 A.M.          CRRES mission briefing and photo
                              opportunity.  For more information
                              call 407/867-2468.

-----------------------------------------------------------------
All events and times are subject to change without notice.  These
reports are filed daily, Monday through Friday, at 12:00 P.M.
EDT.  This is a service of the Internal Communications Branch,
NASA HQ.  Contact: JSTANHOPE or CREDMOND on NASAmail or at
202/453-8425.
-----------------------------------------------------------------
NASA Select TV:  Satcom F2R, Transponder 13, C-Band 72 Degrees
West Longitude, Audio 6.8, Frequency 3960 MHz.
-----------------------------------------------------------------

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

Date: Wed, 20 Jun 90 23:26:30 EDT
From: [e-mail] (Keith F. Lynch)
Cc: Re:HAWAII/[e-mail], [e-mail]

> From: usc!zaphod.mps.ohio-state.edu!uwm.edu!bionet!arisia!cdp![e-mail]

> Some soils in Hawaii contain as much as 31.7% aluminum.

And it's a common food ingredient - check some labels.  But you object
to a few tons being dumped in the air near Hawaii?

> The volcano releases sulfuric acid, whereas SRMs produce a much more
> concentrated hydrochloric acid.

Volcanos produce both acids.  Hydrochloric acid is also found in the
human stomach.

> If there is an accident involving plutonium, it may take 50,000
> years before humans would be allowed to move back!

No isotope of plutonium is more radioactive than the ore it was mined
from, after 600 years.  And the isotope that's used in space probes
has a half life of only 88 years.

> ... one of the most toxic substances known.

Wrong.  I wouldn't sprinkle it on my food, but any exposure much
less than that is pretty safe.  Others on this list mentioned that
Edward Teller offered to eat as much plutonium as a reporter will
eat caffeine.

> The U.S. has launched more than 30 RTGs with a significant failure
> rate of 10-15%.

Does this include the RTGs that were cleaned off and reflown?  How
many broke open?  Any?  How many people were hurt by them?  Any?

> BERYLLIUM and its compounds are severe pulmonary irritants, skin
> irritants and skin sensitizers.

A few years ago I was working on a project that involved handling
beryllium sheet metal.  I wasn't poisoned.  My skin was unharmed.

I suggest you re-evaluate the reliablity of your sources.
                                ...Keith

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

End of SPACE Digest V11 #547
*******************