Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v13_0/v13_078.txt

Internet Message Format | 1991-06-28 | 18KB

Return-path: <[e-mail]>
X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson
Received: from hogtown.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/YbcbgF:00WBwAsY05e>;
          Sun, 27 Jan 91 02:02:41 -0500 (EST)
Message-ID: <[e-mail]>
Precedence: junk
Reply-To: [e-mail]
From: [e-mail]
To: [e-mail]
Date: Sun, 27 Jan 91 02:02:37 -0500 (EST)
Subject: SPACE Digest V13 #078

SPACE Digest                                      Volume 13 : Issue 78

Today's Topics:
Time change made in Gamma Ray Observatory science briefing and spacecraft showing scheduled at KSC on Jan. 29 (Forwarded)
            Salyut 7 is still up!
           Re: space news from Dec 17 AW&ST
           Re: space news from Dec 17 AW&ST
             Re: Ultimate Weapon
              Re: Space Station Weights

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: 24 Jan 91 18:56:24 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Time change made in Gamma Ray Observatory science briefing and spacecraft showing scheduled at KSC on Jan. 29 (Forwarded)


  Mike Braukus
  NASA Headquarters                                 Jan. 24, 1991
  202/453-1549

  Randee Exler
  Goddard Space Flight Center
  301/286-6256

  George Diller
  Kennedy Space Center
  407/867-2468

  KSC Release No. 12-91


  TIME CHANGE MADE IN GAMMA RAY OBSERVATORY SCIENCE BRIEFING AND
  SPACECRAFT SHOWING SCHEDULED AT KSC ON JAN. 29

       The Gamma Ray Observatory (GRO), which is scheduled to be
  launched aboard the Space Shuttle Atlantis in April, will be the
  subject of a science briefing and a showing of the observatory to
  be held at KSC on Tuesday, Jan. 29, at 10:30 a.m. EST.  (Editors
  please note that this is one half hour later than previously
  announced.)

       The Gamma Ray Observatory follows the Hubble Space Telescope
  as the second in NASA's "Great Observatory" series of
  astrophysics observatories.  GRO's four scientific instruments
  are designed to study gamma ray sources in the universe.  GRO
  will be the heaviest NASA low earth-orbiting satellite ever
  deployed from the Space Shuttle, weighing nearly 35,000 pounds.

       Participating in the briefing will be:

  P. Thomas Breakfield, Director of Shuttle Payload Operations,
  Kennedy Space Center

  John R. Hraster, GRO Project Manager,
  Goddard Space Flight Center

  Dr. Donald A. Kniffen, GRO Project Scientist,
  Goddard Space Flight Center

       Also participating on the panel and present at the showing
  of the Gamma Ray Observatory will be the members of the STS-37
  flight crew.  The astronauts flying aboard Atlantis for this
  mission are Steven R. Nagel, Commander; Kenneth D. Cameron,
  Pilot; and Mission Specialists Jay Apt, Linda M. Godwin, and
  Jerry L. Ross.

       The briefing will be carried on NASA Select, Satcom F2R,
  Transponder 13.  The V-2 circuits will also carry audio of the
  briefing and may be dialed directly by calling Area Code
  407/867-1220...1240...1260.

       At the conclusion of the briefing to be held at the KSC News
  Center, media will be provided transportation to the Payload
  Hazardous Servicing Facility (PHSF) for the GRO/astronaut photo
  opportunity.

       Electronic flash is permitted.  However, all lighting
  equipment must be self contained and battery powered.  High
  pressure sodium (orange) is the available light used in the
  facility.

       Appropriate clean room attire will be furnished.  In order
  to maintain payload cleanliness standards, leather or vinyl cases
  are not permitted within the clean room.  Special plastic bags
  will be furnished to carry camera accessories.  Flat, closed-toe
  shoes are required to be worn; no sandles or high heels.  No
  flame producing devices or tobacco products may be taken into the
  facility.

       Media needing accreditation should contact the KSC News
  Center at 407/867-2468 to arrange for badging.   Foreign press
  not possessing U.S. citizenship must arrange for their
  accreditation no later than 10 a.m. on Monday, Jan. 28, to allow
  24 hours for processing.

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

Date: 19 Jan 91 04:41:30 GMT
From: isis!scicom![e-mail]  (Bruce Watson)
Subject: Salyut 7 is still up!



At about 22hr+change UTC something was sighted passing over
Israel.  At first it was thought to be a SCUD missile from Iraq.
(Seems like something serious is going on over there).  My first
thought was that they might have been lucky enogugh to see Salyut 7's
reentry; but no.  CNN reported later that it was the reentry of the
booster rocket from a Soviet spy satellite launch 12 hours earlier.
The CNN correspondent said that it was going from east to west
towards the Mediterranean sea.  That is hardly likely.  It was
in either in a 65 or 81 degree inclination orbit, which at that
latitude would take it from south to north or southwest to
northeast.  Question: why do these reporters get to see something
that in 30+ years of observing I've never seen?

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

Date: Mon, 21 Jan 91 08:40:51 -0500
From: "Allen W. Sherzer" <[e-mail]>
Subject: Re: space news from Dec 17 AW&ST
Newsgroups: sci.space

In article <[e-mail]>:
>I also don't think it would cost that much to man-rate one of the more
>reliable, smaller launchers such as the Delta,

It shouldn't cost anything more.

>if NASA were willing to accept a little more risk of launcher failure.

Actually, the operational record of the Delta, Titan, and Atlas is BETTER
than the operational record of the Shuttle. Realistic Shuttle failure rate
estimates show the Shuttle is no safer than an expendable.

This calls into question the entire 'man rating' process. Why add all that
expense when it doesn't add to safety?

  Allen

--
+----------------------------------------------------------------------------+
|Allen W. Sherzer | America does best when it accepts a challenging mission. |
|   [e-mail]   | We invent well under pressure. Conversely, we stagnate   |
|                 | when caution prevails.   -- Buzz Aldrin                  |

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

Date: 22 Jan 91 19:11:18 GMT
From: sdd.hp.com!wuarchive!julius.cs.uiuc.edu!rpi![e-mail]  (Michael V. Kent)
Subject: Re: space news from Dec 17 AW&ST

In article <[e-mail]> [e-mail] ("Allen W. Sherzer") writes:
>In article <F-6^X6&@rpi.edu> you write:
>>Getting NASA to accept the risk is not your problem.  Your problem is getting
>>Dan Rather and hence John Q. Public to accept the higher risk.  The U. S.
>>manned space program almost ceased to exist in 1986 due to 1 failure in 25
>>flights.
>
>That's not why it happened. For years NASA had been telling people that
>the Shuttle was safe. In fact, it was so safe that they could send up
>congresscritters and even a teacher. It turned out that not only wasn't
>it nearly that safe but it was being run in a manner which made it even
>less safe.
>
>Had NASA been up front with the risks and run a better operation the
>Chalanger disaster PR fallout wouldn't have been that bad. After all,
>Apollo 1 didn't come close to killing Apollo.

Yes, NASA had great claims of the reliability, maintainability, and just plain
ability of the space shuttle.  But NASA didn't get to build the Space Shuttle
they wanted.  The Space Shuttle was given the minimum budget to "get the job
done."  As a result, it doesn't do all of the things NASA wanted a shuttle to
do.  The politics of the early 70's required bringing everyone under the sun
into the Shuttle program to get it built.  The politics of the early 80's
required an accelerated launch schedule.  The politics of the early 90's are
affecting the Space Station in the same way.  The reason for all of this is
that we have a Congress, a public, and a press which has no idea of the
complexity and risks of access to space.

Apollo 1 didn't kill the Apollo program because the Apollo program was a
political one, not a scientific one.  We had the Russians to beat.  Nothing
-- not launch pad fires, nor rocket failures, nor bad weather -- was going
to stand in our way of beating those damn Russians.  That ambition -- for
better or for worse -- is gone forever.  Had Apollo 1 occurred today, the
result would be very similar to the Challenger aftermath.

Michael Kent                                            [e-mail]

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

Date: 24 Jan 91 02:57:57 GMT
From: usc!zaphod.mps.ohio-state.edu!wuarchive!wuphys![e-mail]  (Ian H. Redmount)
Subject: Re: Ultimate Weapon

In article <[e-mail]> [e-mail] (Eric Anderson) writes:
>In article <[e-mail]>
>[e-mail] (Wayne Hayes) writes:
>>
>>To make the Earth into a black hole, you would have to
>>squeeze it into a ball about the size of a grape.
>
>A black hole of such small mass is inherently unstable, and will
>generally "evaporate" (by a somewhat complex process).  The other
>poster who mentioned a black hole over Siberia was referring to a
>proposition that a black hole of much less mass than the Earth was
>responsible for the blast.
>
It might be useful in this regard to keep some relevant magnitudes in
mind.  Firstly, to squeeze the earth into a black hole you would have
to spin it down as well as compress it.  If its angular momentum were
conserved in the compression it would form a naked singularity, not
a black hole.  To form a black hole from a spinning body the ratio
of its angular momentum to its mass squared (in units in which Newton's
constant G and the speed of light c are both 1) must be less than unity.
[See, e.g., ``Gravitation,'' by Misner, Thorne, and Wheeler (Freeman,
San Francisco, 1973), p. 878.]  For the earth this ratio is of order
500.  If you did spin it down before compression, it would form a
Schwarzschild black hole of circumference about 5.5cm---about the
size of a grape, as stated.

Such a black hole is classically stable.  Its lifetime owing to
quantum-mechanical ``Hawking evaporation'' [Hawking, Nature v. 248
(1974), p. 30] is of order T = (M/Mpl)^3 Tpl , where M is the black-hole
mass, Mpl the Planck mass, and Tpl the Planck time.  Since an earth-mass
hole has M~6x10^(27)g while Mpl~2x10^(-5)g and Tpl~10^(-43)s, the hole's
lifetime is of order 3x10^(54)s, or about 3x10^(36) times the present age
of the Universe.  That's not what is usually meant by the phrase
``inherently unstable'' (8-))!

>>The largest black holes postulated, in
>>the centre of some galaxies with masses of several million Suns,
>>*may* just be big enough to swallow a solar system.
>
>A black hole doesn't have to be *nearly* as large as a solar system to
>swallow it, it just needs sufficient "suck"... :-)
>
A typical ``supermassive black hole'' of 10^8 solar masses has a
Schwarzschild radius of about 2AU, sufficient to mess up the solar system
quite nicely.  Of course a solar-mass hole, with a Schwarzschild radius
of 3km, could do nearly as much damage, even in a distant encounter:
At distances beyond a solar radius it would have the same tidal disruptive
effects as a passing star (and no chance of ``seeing'' it).

The largest black hole I ever heard conjectured was one of 10^15-10^16
solar masses.  The Schwarzschild radius of such a hole would be of the
order of a kiloparsec.  The free-fall time from horizon to singularity
in such a hole is of the order of 1000 years [Misner, Thorne, and Wheeler,
op. cit., p. 836]:  A civilization on a swallowed solar system could rise
from prescientific beginnings to the discovery of general relativity in
time to discern its fate!  8-)

Ian H. Redmount

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

Date: Thu, 24 Jan 91 10:24:53 -0500
From: "Allen W. Sherzer" <[e-mail]>
Subject: Re: Space Station Weights
Newsgroups: sci.space
Cc:

In article <[e-mail]> Charles Radley writes:
+ |There is no point in reproducing all the material here.   I was
+ |interested to note that many of the points I had expressed in
+ |sci.space  are independently raised in the NASA Critique.
++ ...and are adequately dismissed in the LLNL reply.
+  You are being dogmatic.  Some of the NASA answers I agreed with, and
+some of the LLNL rebuttals were good too.

So which answers NASA gave did you find compelling?

+I was particularly
+impressed by LLNL actually referencing NASA's own studies in some of
+their rebut als, giving the NASA critique the apparance of being
+unaware of its own research results.

Appearance? What reason do you have to think NASA was AWARE of their
own research? They never addressed it in their responce.

+If congress appropriated more money it would be interesting to
+continue the study.

Congress HAS appropriated money to continue.

+There simply is no money in the NASA budget to study it.    And the budget
+continues to shrink.

I doubt NASA could impliment it in their current state anyway. Maybe in
a few years. As to shrinking budgets, they will be less of a problem because
they are spending far less money.

++ BTW, since you
++ saw the critique, can you tell me who wrote it and where they are
++ from?
+  No idea.   Irrelevant anyway,

I don't think so. It tells me that the persons who wrote the critique
didn't want their names associated with it.

+they got no money to continue any
+evaluation, unless you can persuade somebody to do it after hours.

They have enough money to start prototypeing this year.

+But then it would not have the authority of NASA.....

No, just the authority of LLNL and the DoE.

++So what. If the approach is good then the politics of the people
++ advocating it are not relevant!
+  Then why does LLNL waste valuable time with that stuff ?  NASA's
+charter is technical, not political.

Because as Mr. Faering points out the the US alone nature reduces
program cost and schedule. I'll admit that Dr. Wood is a very patriotic
person (like most DoE people) but I don't see the relevance.

+The vu-graphs show no weight or
+cost allocations for science.   LNNL replies that will be handled ad
+hoc after the fact.

Compared to the NASA 90 day SEI study, LLNL allocates the same percentage
of its budget to science. Because of its compressed schedult we will see
more science at any point in time with LLNL than NASA.

Even compared to Freedom it would be better. Had this plan been funded when
it first came out we would have a large station in orbit doing life science
work with huge growth potential for other work one year BEFORE Freedom FEL.

+Freedom was expensive & heavy because it included a large up
+front science capability.

No, Freedom is heavy and expensive because they didn't have a mission
for it, let the contractors and centers run open loop, and ignored
system integration issues for years. The Reston program office is ONLY
NOW (six years into the program) getting a handle on the situation. Now
that they know what's going on, NASA wants to move the program office
and start all over again.

+Crew transportation remains unaccounted for, the LLNL vu-graphs
+presented no cost or weight data for that big ticket item.

I'm sure there is a lot of stuff unaccounted for. We are only seeing
the result of a small study effort. They could use a Soyuz in a pinch
so an inexpensive solution exists.

+   Your space activist newsletter also mentions External Tank and
+LLNL in the same paragraph.   Why ?

Because since we need to start over again we should put more thought
into it this time. I like LLNL and think it can work but I may be
wrong. It would be nice to have an inexpensive fallback in case I
am wrong.

+Which is better ?

I have no idea. For a small fraction of the cost of Freedom we
could prototype several alternatives. Whichever works can then
be expanded on. I suspect we will find each alternative has good
and bad points (I have always thought a ET could be made into a
wonderful dry dock to repair/integrate satellites).

+I called External Tank corp and they have minimal technical data, no mass
+budgets.

I was refering to the SSI External Tank Study.

+ET seems oversold.

Could well be. I have seen several alternative ideas from LLNL to ET
to even stranger things. I'm sure they all won't work.

+How can you advocate to our lawmakers that
+we should fund such a system ?

Because it might work. At least it's worth looking into.

+   Your efforts are on the verge of permanently grounding the
+manned space program.  Already PMC for Freedom is gone, which was
+its principle purpose.

There is no stronger supporter of manned space than I. What is harming
manned space is not me but rather our aerospace full employment way
of doing things.

Consider Freedom. Congress said to NASA: for the next ten years you can
have $1.5B growing to $2B; what can you build for that? NASA studied the
problem and came back with something like CDSF or ISF at ten times the
cost. There is a lot of space work which isn't happening because of this
waste.

+This is a perfect illustration that it is the CONGRESS, advised by
+such as you, whose on-again off-again mood swings are bleeding the
+program, yet all you do is blame NASA......

Congress is indeed a large part of the problem but until NASA realizes
their share nothing will happen.

But remember, sometimes Congress helps NASA out. Sources of Freedom
said last July that they didn't want full funding for Freedom. They
needed a cut so they could blame the redesign on it.

      Allen
--
+----------------------------------------------------------------------------+
|Allen W. Sherzer | America does best when it accepts a challenging mission. |
|   [e-mail]   | We invent well under pressure. Conversely, we stagnate   |
|                 | when caution prevails.   -- Buzz Aldrin                  |

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

End of SPACE Digest V13 #078
*******************