Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_4/V11_411.TXT

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Subject: SPACE Digest V11 #411

SPACE Digest                                     Volume 11 : Issue 411

Today's Topics:
         NASA Headline News for 05/16/90 (Forwarded)
               Re: Oxygen prebreathing
    Re: Terraforming Venus (was: Manned mission to Venus)
              Re: Space Shuttle
               Spectroscopy on the HST
     Hubble Space Telescope Update - 05/16/90 (Forwarded)
               Re: EXOSAT observations
----------------------------------------------------------------------

Date: 16 May 90 16:32:10 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 05/16/90 (Forwarded)

-----------------------------------------------------------------
Wednesday, May 16, 1990               Audio Service: 202/755-1788
-----------------------------------------------------------------

This is NASA Headline News for Wednesday, May 16....

Kennedy Space Center technicians have removed a faulty coolant
valve from the shuttle Columbia.  The analysis revealed fragments
of a small crushed filter.  This may explain the reduced flow of
Freon in the Columbia's coolant system.  The valve replacement
activities begin today following a refill and test of the coolant
loop.  A new launch target date will be determined the end of
this week.

A protective net covering the Astro-1 payload served well during
the valve change.  Technicians servicing the coolant system
worked for the first time in vertical position.  Meanwhile, the
Broad Band X-ray Telescope, one of the Astro-1 telescopes, is
scheduled to be serviced with liquid argon on Thursday.  Closeout
activities of the airlock and avionics bays in the aft
compartment are underway.

                            ********

Since the launch of the Hubble Space Telescope, astronomers say
yesterday was as exciting as the day word came it was finally on
its own.  Controllers successfully locked on to guide stars and
used them for focusing.  The line of sight test scans went
well.  Operators continue to update a sluggish fixed head star
tracker and plans to begin the next acquisition sequence are
proceeding on schedule.

                            ********

It looks like a mission to retrieve a stranded Intelsat
communications satellite launched last March may be possible.
Associated Press reports payload manager William Green said if
Intelsat will pay the proposed $130 million in cost, NASA could
rescue the 5-ton spacecraft in late 1991 or 1992.  Intelsat will
decide next month.

                            ********

Spacecraft closeout activities at Kennedy Space Center have begun
to move the ROSAT to the launch pad.  The attach fitting which
connects the satellite with the Delta second stage is bolted on
and today the ROSAT will be installed in a transportation
canister.  The move to Complex 17 is scheduled for early tomorrow
morning. The launch target date is scheduled for May 31.

                            ********







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



Wednesday, May 16..................

                 12:00 Noon        Launch of Consort III, micro-
                                   gravity experiment flight from
                                   White Sands New Mexico.
                                   (Tape replay)

Thursday, May 17...................

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

                 12:00-2:00 P.M.   AMBLER planetary
                                   robot vehicle video followed
                                   by a series of video programs
                                   including:
                                   Mercury Program.
                                   Earth life of a spacecraft.
                                   Project Laser.


All events and times are subject to change without notice.
-----------------------------------------------------------------
NASA Select TV: Satcom F2R, Transponder 13, C-Band 72 Degrees
West Longitude, Audio 6.8, Frequency 3960 MHz.
-----------------------------------------------------------------
These reports are filed daily, Monday through Friday, at 12 Noon,
EDT.  This is a service of the Internal Communications Branch,
NASA HQ.

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

Date: Wed, 16 May 90 15:08:06 EDT
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Re: Oxygen prebreathing


>From: attcan!utgpu!utzoo![e-mail]  (Henry Spencer)

>>I don't know what "prebreathing" refers to, or why it is necessary.  Could
>>someone explain this?  Thanks in advance.

>Current spacesuits use a pure-oxygen atmosphere at the lowest possible
>pressure -- 2-3 psi -- because higher pressures just make the suits
>too stiff.  Trouble is, if you rapidly drop an astronaut from 15 psi to
>2, he's got a very good chance of getting "the bends", as nitrogen in
>solution in his body comes out as bubbles.  The only way to prevent this
>is to spend quite a while breathing pure oxygen (typically via a mask)
>first, to get all the nitrogen out of your body.

I've been meaning to ask - in the discussions of pressure changes (i.e.
decompression, breathing vacuum), there has been mention of the risks from
bubbles formed out of dissolved nitrogen and other gases. Oxygen bubbling
never seems to be mentioned. Is that because the oxygen is chemically bound
to the hemoglobin in the blood? This seems like the logical explanation to
me. Otherwise, going from 15 psi pure oxygen to 3 psi oxygen in the
prebreathing cycle would replace nitrogen bubbles with oxygen bubbles.
                 John Roberts
                 [e-mail]

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

Date: 16 May 90 21:22:00 GMT
From: thorin!homer![e-mail]  (Jonathan Leech)
Subject: Re: Terraforming Venus (was: Manned mission to Venus)

In article <[e-mail]> [e-mail] (Mark SOKOLOWSKI) writes:
>was there really some kind of cooling down?). In other words we will
>WARM UP Venus instead of cooling it.

    Insignificant, the point is to reduce the heat trap of the
atmosphere by changing its composition.

>And beside, I don't see we should
>disfigurate the venusian landscapes with craters. For God's sake,
>ALL the solid objects in our solar system (except Venus and Earth) are
>SURSATURATED with those boring, destructive round circles, so please,
>DON'T DESTROY THE BEAUTIE OF VENUS!!!!!

    This will come as a surprise to observers of Io and Europa (for
example).  If you take the time to learn a minimal amount of planetary
science and physics, your opinions might be better received.
--
    Jon Leech ([e-mail])    __@/
    ``The experiment must be wrong'' - Richard Feynman (as quoted by
    Eugen Merzbacher), upon hearing that experimental data did not
    agree with theoretical predictions. Feynman was correct :-)

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

Date: 16 May 90 20:09:48 GMT
From: swrinde!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Space Shuttle

In article <[e-mail]6> [e-mail] writes:
>a couple of trucks pulled up and connected three large hoses
>(opprox one foot diameter) to the shuttle, he asked me the purpose
>of these hoses.

Hoses that big will be for gas, not fluids, and by far the obvious
winner is cooling air.  The exterior of the shuttle is *hot* after
landing; the worst-case heating for payloads in the payload bay is
actually after landing, as reentry heat soaks through the structure.
I don't know for sure, but I'd be surprised if those hoses weren't for
cooling air for the cabin and (perhaps) the payload bay.
--
Life is too short to spend    |     Henry Spencer at U of Toronto Zoology
debugging Intel parts. -Van J.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 15 May 90 22:15:01 GMT
From: stretch.cs.mun.ca![e-mail]  (Chris Paulse)
Subject: Spectroscopy on the HST


I've seen mentioned in the bulletins regarding the Hubble Space
Telescope the Goddard High Resolution Spectrograph.  Would anyone be
so kind as to fill me in on what this apparatus is (will be)
capable of doing?

Regards
Chris Paulse
Memorial Univ.

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

Date: 16 May 90 16:07:11 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Hubble Space Telescope Update - 05/16/90 (Forwarded)

NEW YORK TIMES -- MAY 16

"Hubble Telescope Able To Focus"
By John Noble Wilford

"After three troubled weeks trying to steady a wiggling
spacecraft and fix its sights on the heavens, ground controllers
said yesterday that the Hubble Space Telescope was responding
reliably to commands and was for the first time focusing on guide
stars."

The Times says this latest activity clears the way for the
telescope's first picture on Sunday.  The story also reports NASA
officials are encouraged by this and quotes telescope test chief
Mike Harrington saying "it was a very satisfying day."

The Times also reports that other spacecraft tests including
those on the five instruments have been successful.

In conclusion, the paper quotes from telescope chief scientist
Dr. Ed Weiler, saying "for the first time we now are sure we know
where we are pointing and how to lock on to stars and maintain
our position.  It's a significant accomplishment."

                      * * * * * * * *

USA TODAY -- MAY 16

"Hubble Sets Up for Photo Show Sunday"

"The Hubble space telescope is pleasing its NASA handlers at
last."

USA Today says jubilant managers reported the telescope was able
to lock onto the correct set of guidance stars and quotes deputy
project manager Jean Olivier as saying "we've got high hopes
now."

The paper also quotes telescope scientist Dr. Weiler saying "as
an astronomer, it's the most exciting day since the launch."

USA Today, cautions that the telescope's troubles aren't over
just yet, though, citing the wobble which occurs each time the
telescope emerges from the Earth's shadow into sunlight.

                      * * * * * * * *

UNITED PRESS INTERNATIONAL -- MAY 16

"Hubble Space Telescope Mirrors Focused"
By Rob Stein

"Jubilant NASA scientists began focusing the Hubble Space
Telescope like a pair of giant binoculars and predicted the
orbital observatory could take its historic first picture of the
heavens Sunday."

The UPI reports that engineers sent commands Tuesday that moved
one of the two near-perfect mirrors about 240-thousandths of an
inch in the first steps of painstakingly focusing the telescope's
optical system.

The wire reports the work was part of a 36-hour process involving
the focusing of the secondary mirror which will be followed by a
38-hour guidance system test and then another 36-hour focusing
process.

UPI states that if all goes well, the first picture, of a three-
billion-year-old star cluster located about 1,500 light years
from Earth, could be taken Sunday afternoon but cautions the
picture is actually part of a test and not expected to produce
new discoveries.
       _   _____    _
      | | |  __ \  | |       Ron Baalke           |  [e-mail]
      | | | |__) | | |       Jet Propulsion Lab   |  [e-mail]
   ___| | |  ___/  | |___    M/S 301-355          |
  |_____| |_|      |_____|   Pasadena, CA 91109   |

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

Date: 16 May 90 18:45:48 GMT
From: mcgill-vision!quiche!calvin![e-mail]  (Mark SOKOLOWSKI)
Subject: Re: EXOSAT observations

Newsgroups: sci.space
Subject: Re: Manned Mission To Venus
Summary:
References: <[e-mail]>
Sender:
Reply-To: [e-mail] (Mark SOKOLOWSKI)
Followup-To:
Distribution:
Organization: SOCS, McGill University, Montreal, Canada
Keywords:

In article <[e-mail]> [e-mail] writes:
>I believe you are correct that the visual distortions may not be
>'true'.  It's my understanding that it's a real near thing, though,
>which seems to indicate that in some places on Venus, given some
>'weather' conditions, it might or might not happen.  I'd be
>disinclined to bet one way or the other.
>
Many people are mistaken by the way those photos were taken i.e.
unlike the Vikings, the Veneras cameras scan an area centered on
the ground just beside the probe, with only the extreme edges of
the photos showing a glimpse of a horizon.
>
>I'm afraid you're going to have to explain to me just how you arrive
>at the conclusion that Venerean soil is "the same as our own in
>terms of composition" on the basis of some "reequilibrated" (i.e.,
>artificially colored) photos.
>
It's simply the team of russian scientists that modified the digitilized
pictures with data taking in account an oversaturation in yellow light.
In that way they obtained a photo looking like very much those of
solidified lava beds in Hawaii, or basalitic ocean floors (Venera 13,
if I recall it well).
>
>> I don't see why Venus would be so bleak. After all it is brighter on its
>> surface than in the cold darkness of the Oceans.
>
>True, but how would you know what's outside anyway?  Even if you could
>get there and survive to the surface, I can't imagine being able to do
>so for any length of time in anything with a weak point like a window in
>it.  And what does the heat/cold of outside matter, since you're not
>going to be walking around in it anyway?
>
How can you tell me I won't be able to walk ouside. Any kitchen oven
experiences the same kind of temperatures as those on Venus, and
you don't need any special equipement except gloves to handle the
things you put in it. The fact that the athmospheric pressure is 90
times greater there shouldn't be a big problem, since we will soon be
able to breath hydrox at more than 100 athmospheres, as recent
deep water experiments have shown.
>
>If you're going to live in a big can, why does it matter where the
>can is?  Why put it the most difficult place possible?  Personally,
>I'd rather live in a space settlement.  You could have everything
>you list as being the advantages of living on a ball of dirt, plus
>just think about being able to have zero-g at will.  And think about
>the view of the STARS!
>
It's a matter of taste. I like Venus, I like venusian landscapes. I don't
deny that there are people that won't want to go there. The thing is that
living in a manned venusian base won't be much more difficult than on any
other base in the solar system. And imagine: You'll be standing on a
solid surface greater than that of all the other solid bodies of the
solar system combined!!! All this world just for you!!! I'll be glad to
become a venusian.
>
>Only if you enjoy being burned and corroded to death.  We can build
>things that will keep air in and space out.  We can't build things
>that will keep Venus out of the people-pipe.  It's really that
>simple.
>
We won't need to build it. A small refrigeration unit powered by a
few hundred watts can maintain the temperature of a large room the
necessary 400 K below that of the exterior (with appropriate insulation),
and the pressure of hydrox will equal that outside: We will need only
a few centimeters of insulation. Don't forget that the luck is that
Venus has an athmosphere as significant as that of Earth's, so we don't
have to worry about the dangers of vacuum. As a plus, because
people will live in a 100 athmospheres environment, you'll be able
TO FLY, just as in 0 G in a space station.
>
>You lose.  I can't imagine what we could get from the Moon for
>weapons use that we don't already have.  The *big* thing often
>mentioned for the moon (other than sheer mass for shielding - which
>*could* be used for battle stations, but rock is hardly 'rare') is
>Helium-3.  This is for *power* fusion.  Bomb fusion we've already
>got.
>
False, only Angola and a few unstable african countries are providing
Tungstene, Zirconium, and other rare metals compulsory in the design
of modern military helicopters and jets, to only cite an example. Not
to mention the strategic importance of South Africa for the raw materials
essential to the weapons of the occidental world. So were will we go when
appartheit will be dismantled there :-)????

Mark S.
-------

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

End of SPACE Digest V11 #411
*******************