Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_6/V13_609.TXT

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Subject: SPACE Digest V13 #609

SPACE Digest                                     Volume 13 : Issue 609

Today's Topics:
      Re: Mars polar sampler (was:  Re: Why the space station?)
            Mars Quote Correction
    Re: Revising a biased history of space science funding
             Re: Gravity vs. Mass
      Re: Crater Found From 65-Million Year Old Asteriod
              Re: Budget Numbers Wanted
               AURA members, activities
             Re: Laser launchers
          Re: What comes after Fred's death?
         NASA Headline News for 05/21/91 (Forwarded)

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: 22 May 91 14:24:22 GMT
From: agate!spool.mu.edu!samsung!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: Mars polar sampler (was:  Re: Why the space station?)


\In article <[e-mail]>, Steve Schaper (ss) writes:
/ss> Would it possibly be less costly to send the polar corer probe
\ss> with onboard electron microscope, gas chromatograph, etc,

And Richard Caley responded:
RC\Maybe, but it would be a _real_ pain when you and discovered that what
RC/you really needed there was microsubluction boozalatron which, of
RC\course, is developed 2 years after the probe is launched.

Is there any consensus out there as to what to do to a martian
polar core section if space aliens landed tomorrow and sold you
one, or someone figured out a way to get some samples tomorrow?

I mean something besides the obvious: write lots and lots of masters
and PhD theses on it.

--
Phil Fraering || Usenet (?):[e-mail] || YellNet: 318/365-5418
''It hardly mattered now; it was, in fact, a fine and enviable
madness, this delusion that all questions have answers, and nothing is
beyond the reach of a strong left arm.`` - Larry Niven and Jerry
Pournelle, _The Mote in God's Eye_

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

Date: Thu, 23 May 91 11:02:10 PDT
From: [e-mail]
X-Vmsmail-To: UTADNX::UTSPAN::AMES::"[e-mail]"
Subject: Mars Quote Correction


CORRECTION:

In a recent posting I cited this quote:

"Mars is essentially in the same orbit.  Mars is somewhat the same
 distance from the Sun, which is very important.  We have seen pictures
 where there are canals, we believe, and water.  If there is water,
 there is oxygen.  If oxygen, that means we can breathe."
 -- J. Danforth Quayle, 18 November, 1989

In fact, according to Vol. 35, No. 1 (January, 1990) of the _Bulletin of
the American Physical Society_, Quayle said this in an 11 August, 1989
interview on CNN (by way of explaining why the US should undertake a
manned mission to Mars).  Apparently it was rerun on 18 November, since
that was the date listed in my other source, _The Quayle Quarterly_.

_____________
Dale M. Greer, whose opinions are not to be confused with those of the
Center for Space Sciences, U.T. at Dallas, UTSPAN::UTADNX::UTDSSA::GREER
"...what a waste it is to lose one's mind." - Dan Quayle

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

Date: 23 May 91 17:47:26 GMT
From: csus.edu!wuarchive!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Revising a biased history of space science funding

In article <[e-mail]> [e-mail] (Karl Stapelfeldt) writes:
>     Much of this unmanned exploration funding was directly related
>to supporting the manned lunar landings with automated
>precursor missions.  The scientific results of Lunar Orbiter and
>Surveyor were a direct offshoot of the manned program's need for
>landing site surveys.  It is preposterous to quote these budget
>numbers out of their programmatic context and imply that they
>demonstrate how well unmanned exploration does without budget pressure
>from manned programs.

In fairness, however, there is a flip side to this:  the scientific results
of those missions were a result of a *coordinated program* of exploration,
intended to culminate in ongoing manned exploration.  Neither Surveyor nor
Lunar Orbiter was dedicated to Apollo support, although both got high
funding priority because of that role and accordingly gave that role first
priority in their activities.  Surveyor's Apollo-support work mostly ended
with the first mission; some would argue that it ended with the first image,
showing that Surveyor 1's footpad -- designed to exert the same surface
pressure as those of the Apollo LM -- had not sunk far into the surface.
Lunar Orbiter's Apollo work was complete midway through the third mission
(out of a total of five).

Agreed that those programs have to be viewed in context... but the fact
that said context was an organized program with specific goals is just
as important as the fact that manned exploration was one of those goals.
--
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  [e-mail]  utzoo!henry

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

Date: 23 May 91 20:15:49 GMT
From: att!cbnewse!cbnewsd![e-mail]  (lewis.h.mammel..jr)
Subject: Re: Gravity vs. Mass


What's the largest granite sphere through which a 1 meter diameter
hole could be drilled without having it collapse due to self-gravity ?

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

Date: 15 May 91 17:02:18 GMT
From: olivea!samsung!think.com!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!pitt!nss![e-mail]  (Paul Blase)
Subject: Re: Crater Found From 65-Million Year Old Asteriod

to: [e-mail] (John A. Weeks III)

 JA> CNN is running a story tonight about the asteriod that
 JA> supposedly killed off the dinosaurs 65-million years ago.  They
 JA> report that `scientists' have found the remains of a 102 mile
 JA> wide crater left by the impact.  The crater lies partly on the
 JA> Yuctan, with much of it submerged in the Gulf.

No need to put quotes around 'scientists'; the crater was originally
discovered by oil exploration teams, scientists have just got around
to finding additional confirmation (according to the story I read,
the original evidence is several years old, but the oil company
was sitting on it for other reasons (having to do with keeping the
oil field confidential)).

 JA> This is where it gets really wierd: CNN further reported that
 JA> this is evidence that a gigantic impact killed off the
 JA> dinosaurs.  I was under the impression that an impact was
 JA> suspected to have happend all along based on the Iridum layer,
 JA> but that no one has connected the extinction to the impact.
 JA> After all, there was an earlier massive dinosaur extinction at
 JA> then end of the Jurassic period, but no suspected impact.

Although the iridium layer is pretty good evidence for an impact, no one
had ever found the crater from the impact that produced it.
Some scientists theorized that the layer could have been produced
volcanically.  I'm not sure what you mean by "no one has connected....",
that connection was what was causing all of the fuss in the first place!
Actually, meteor strikes are suspected in many extinctions, although the
evidence is, of course, somewhat fuzzy at present.

--- via Silver Xpress V2.26 [NR]
--
Paul Blase - via FidoNet node 1:129/104
UUCP: ...!pitt!nss!Paul.Blase
INTERNET: [e-mail]

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

Date: 21 May 91 13:21:10 GMT
From: olivea!samsung!news.cs.indiana.edu!widener!hela![e-mail]  (Allen W. Sherzer)
Subject: Re: Budget Numbers Wanted

In article <[e-mail]> [e-mail] (William Dow Rieder) writes:

>*Original NASA budget - what the President asked for.

The budget delivered to Congress requests $15.75 billion. NASA asked for
$17.7 billion.

>    (with breakdowns by category/progect)

There are about four pages of breakdowns. I can't type that in now.
However, the Administration requested $2.03 billion for the station.
$2.9 billion was for Space Science and Applications.

>*Original HUD/whatever budget

Sorry I don't have those numbers handy.

  Allen
--
+---------------------------------------------------------------------------+
|Allen W. Sherzer |        Allen's tactics are too tricky to deal with      |
|   [e-mail]   |             -- Harel Barzilai                           |
+---------------------------------------------------------------------------+

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

Date: 21 May 91 05:06:54 GMT
From: sdd.hp.com!think.com!paperboy!hsdndev!dartvax!mars!nic!kira!emily![e-mail]  (Garrett Wollman)
Subject: AURA members, activities

In my acronym posting, I mention that AURA, the Association of
Universities for Research in Astronomy, operates STScI, and (I think)
that JHU is one of the members.  I would like to know, preferably from
someone in a position to know, who the other members of AURA are, and
what their other activities besides STScI are.  The first respondent
will get a mention in the credits, as usual.  (Unless it's someone
who's already in the credits.)

Special to sci.astro readers... do you think I should extend my
posting of the full acronym list from just sci.space and alt.tla to
sci.astro as well?  I am very much inclined towards avoiding real
astro issues unless they can somehow be integrated into the space
material; do you think this would be useful?

Special to sci.space readers... any idea what the breakdown is for
people who read sci.space.shuttle who do/do not also read either
sci.space or sci.astro?  Or should I just stick to sci.space and not
worry about them?

Advance notice... when the acronym list is next posted, probably on
Memorial Day (not sure which one, the actual day or the Monday
holiday), I will also be posting diffs.  Hopefully this will make it
easier for people to just look at the new material without wading
through the old stuff.

-GAWollman

Garrett A. Wollman - [e-mail]

Disclaimer:  I'm not even sure this represents *my* opinion, never
mind UVM's, EMBA's, EMBA-CF's, or indeed anyone else's.

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

Date: 21 May 91 15:31:57 GMT
From: umich!ox.com!fmsrl7![e-mail]  (Ron Carter)
Subject: Re: Laser launchers

In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>So laser launchers *aren't* HLV replacements. That's where this all
>started. I thought I was thinking *small* when I postulated 1000 kg.

For some purposes, yes, laser launchers *are* HLV replacements.
Not for sending up large payloads in one piece, but for cheap
shipment of bulk commodities.  Rocket fuel, water, air and food
will be required in considerable quantity by a vigorous space
station or manned planetary mission effort, and it makes great
sense to cut those shipment costs down to the bone.  Losing
30 lbs of food, or ice, or frozen hydrazine is no big deal,
so a great deal worse reliability can be tolerated in a laser
launcher than in an HLV.  Flaw tolerance cuts costs.

There is a further reason to have a laser launcher be small.
Given current commodity requirements, a large launcher must
be amortized over a small number of payloads, while a small
launcher can be amortized over many payloads.  A laser launcher's
capital costs scale roughly with payload size, so for best
return, it is optimal to make the payloads small and then
run the launcher all day long.  At 30 pounds every 4 minutes,
it takes only 89 hours to launch a Titan IV worth of payload.
I don't think a Titan IV pad can be turned around in < 4 days,
and I doubt the assembly line can build them that fast.
75,000 lbs/week is a pretty fast launch rate, no?

>>>.... We must attain the highest specific impulse that we can to keep
>>There's another faulty assumption....  Typical rockets run 20 and up.
>Less than one order of magnitude difference.

(We're up over 2 orders of magnitude so far.)

>You're right there. I went back and checked the articles where the figure
>came from. 1 kw/cm^2 .... big oops, I multiplied by 100 instead of 10,000
>to convert from cm^2 to m^2.

(Now make that 4 orders of magnitude.  It really looks different now.)

Good, you found the article.  Can you please cite the publications
and authors, and tell me if the 1 KW/cm^2 is the point of onset for
ionization, or thermal blooming?  I'll wager it's the latter.
And please tell what wavelength the authors were using, it is
very significant.

Incidentally, the characteristic impedance of free space is about
377 ohms per square, if memory serves.  1 KW/cm^2 implies an RMS
electric field strength of 614 volts/cm, which is nowhere near
the dielectric breakdown point of air.  100 GW/m^2 is 10 MW/cm^2,
implying an RMS FS of about 61 KV/cm.  That's where I'd start
to worry about things turning to plasma.

Incidentally, Scientific American published a design for a
nitrogen laser some years ago.  The power output (in short
pulses) was several megawatts.  It did not ionize air.

I haven't found my previous tether study.  I'll have to re-do
it from the ground up, I'm afraid.  It might not get done for
a week or two.

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

Date: 22 May 91 00:06:54 GMT
From: sdd.hp.com!wuarchive!waikato.ac.nz![e-mail]
Subject: Re: What comes after Fred's death?

In article <[e-mail]>, [e-mail] (Henry Spencer) writes:
> In article <[e-mail]> [e-mail] (Steve Willner) writes:
>>Hasn't it occurred to anyone that life sciences research (keeping a
>>couple of astronauts in orbit for a year or so) can be done without a
>>space station?  All that should be needed are another couple of
>>shuttle orbiters, extended duration modifications (up to 30 days is
>>already planned), and rendezvous capability.
>
> Much of the life-sciences work people would like to do involves experimental
> animals other than astronauts, and non-trivial amounts of hardware.  Taking
> it from one orbiter to another would be quite a job.
> --
> And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
> "beans are more important".             |  [e-mail]  utzoo!henry

    To do this you would need two shuttles up a once (obviously). I may be
wrong but I don't think mission control can handel this.

    What about an extended extended duration orbitter. A couple of shuttle
flights (or unmanned rockets) put up a food canister and a space lab (more than
one possible). The shuttle to be used is launched with extra fuel for thrusters
in it's payload bay. Up it goes and you have a temporary space station. Might
also be good having a shuttle up there permantly (satelite repairs, etc).

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

Date: 21 May 91 20:05:01 GMT
From: [e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 05/21/91 (Forwarded)


             Headline News
Internal Communications Branch (P-2) NASA Headquarters

  Tuesday, May 21, 1991    Audio Service: 202 / 755-1788

This is NASA Headline News for Tuesday, May 21, 1991 . . .

Launch officials at Kennedy Space Center have delayed the lift-off of
the STS-40 Columbia mission to no earlier than Friday.  Efforts
continue to understand data received yesterday concerning a main
propulsion system temperature sensor that failed during cryogenic
propellant loading last fall, and replacement of a balky General
Purpose Computer (GPC #4) is being considered.  Also in question is the
performance of a multiplexer-demultiplexer unit (MDM), which functions
as an interface between the Orbiter/Solid Rocket Booster (SRB)
hydraulics, SRB ordnance, orbital maneuvering and reaction control
systems, and the Orbiter's GPCs.

Mission management teams are currently meeting to address these issues
and to determine what actions may be necessary to insure flight
readiness of Columbia for the STS- 40 life science mission.

NASA Test Director Mike Leinsbach noted during this morning's countdown
status briefing, that the  hold was in accordance with safety
recommendations  developed after the Challenger accident.  The hold was
also made in time to decide not to load research animals aboard
Columbia's Spacelab module, allowing more flexibility for
rescheduling.

                   * * * * * * * * * * * * * * * *

In a press briefing yesterday afternoon, NASA space flight chief, Dr.
William B. Lenoir, reiterated NASA's disappointment in the House
Appropriations Subcommittee on VA, HUD and Independent Agencies'
proposal to scuttle the Space Station program.  Lenoir was optimistic
that the program would continue and he emphasized its importance to
U.S. space technology and space operations leadership, aerospace
economic competitiveness, education, space science, commercial
applications, international cooperation and aerospace jobs.

                   * * * * * * * * * * * * * * * *

Test data analysis and hardware inspection are currently underway at
Stennis Space Center on the last of Space Shuttle Endeavour's main
engines.  Engine 2035 testing was completed Friday, bringing to four
(three flight engines and a spare) the number of Endeavour SSME's that
have undergone acceptance testing.

The first Pratt & Whitney high-pressure fuel turbopump for the Space
Shuttle Main Engine arrived at Stennis Space Center over the weekend.
The fuel turbopump is expected to undergo testing on an SSME.  Stennis
personnel tested a high-pressure oxidizer pump on a research and
development main engine in March.

* * * * * * * * * * * * * * * * * * *

Admiral Truly will deliver the commencement address at Stevens
Institute of Technology in Hoboken, New Jersey, today.

---------------------------------------------------
---------------------
NOTE:
NASA Select television schedule undergoing revision at Headline News
press time.


This report is filed daily at noon, Monday through Friday.  It is a
service of NASA's Office of Public Affairs.  The contact is Charles
Redmond, 202/453-8425 or CREDMOND on NASAmail.  NASA Select TV is
carried on GE Satcom F2R, transponder 13, C-Band, 72 degrees West
Longitude, transponder frequency is 3960 megaHertz, audio is offset 6.8
MHz, polarization is vertical.

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

End of SPACE Digest V13 #609
*******************