Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V08/V8_327.TXT

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Date: Wed, 17 Aug 88 01:05:28 PDT
From: Ted Anderson <[e-mail]>
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Subject: SPACE Digest V8 #327

SPACE Digest                                      Volume 8 : Issue 327

Today's Topics:
           Most distant galaxy detected (Forwarded)
            Re: 95% vs. 99.9% reliability
                Re: Satellites
                August shower.
              Electromagnetic Launchers
            Re: 95% vs. 99.9% reliability
                Re: Satellites
----------------------------------------------------------------------

Date: 8 Aug 88 15:27:37 GMT
From: [e-mail]  (Peter E. Yee)
Subject: Most distant galaxy detected (Forwarded)

Charles Redmond
Headquarters, Washington, D.C.                   August 8, l988

Ray Villard
Space Telescope Science Institute, Baltimore, Md.


RELEASE:  88-111

MOST DISTANT GALAXY DETECTED

     Astronomers at NASA's Space Telescope Science Institute,
Baltimore, Md., and the University of California at Berkeley have
uncovered the most distant galaxy yet seen.

     Called 4C41.17, the newly-discovered galaxy is located at an
estimated distance of 15 billion light years -- more than 90
percent of the distance to the visible limits of the universe.

     The discovery was made by Ken Chambers, a graduate student
at Johns Hopkins University; George Miley, professor of astronomy
on leave from Leiden University, Netherlands, and stationed by
the European Space Agency (ESA) at the Space Telescope Science
Institute; and Will van Breugel of the University of California
at Berkeley.

     Extremely distant galaxies are of great interest to
astronomers because radiation from these galaxies takes billions
of years to reach the Earth.  The distance established for
4C41.17 means that what is being seen happened only a few billion
years after the Big Bang, which marked the beginning of the
universe.

     Such remote galaxies can be used to study the early stages
of the universe.  According to current cosmological theories, the
physical conditions of the early universe were very different
from those encountered today.  Hence, remote galaxies like
4C41.17 may help forge a better understanding of how galaxies
have evolved since the time of the Big Bang.

     Galaxy 4C41.17 also is intriguing because it has a
fundamentally different appearance from nearby galaxies.  It and
other high red-shift galaxies have unique, enigmatic properties,
say the researchers.  They certainly are not "normal" galaxies.

     Galaxy 4C41.17 is one of several extremely distant galaxies
discovered by Chambers, Miley and van Breugel during the past few
months using their newly-developed search strategy.  Their
strategy makes use of the fact that galaxies such as 4C41.17
produce intense radio emissions, millions of times more powerful
than those of our own Milky Way galaxy.  The unique radio
spectrum of these objects can be used to select the most powerful
and most distant of them.

     The researchers find that such galaxies have a distinctive
radio spectrum which peaks and then drops off at a much faster
rate than found in nearby radio galaxies.  This "ultra-steep"
spectrum indicates that the galaxies are intrinsically quite
luminous, though they appear very faint because of their
tremendous distances from Earth.

     Galaxy 4C41.17 was first identified in a survey of 51
distant radio galaxies conducted by the researchers.  Next,
detailed radio observations of 4C41.17 were made at various
frequencies using the Very Large Array Radio Telescope Facility
near Socorro, N.M.

     Those observations were then followed by an optical search
with the 2.1 meter telescope at Kitt Peak National Observatory.
A long-exposure image revealed 4C41.17's optical component which
has the characteristic appearance of a galaxy because the
component characteristic is elongated rather than star-like.

     Once the galaxy was identified optically, the researchers
established its huge distance by taking an optical spectrum which
uncovered emission lines in carbon and hydrogen produced by the
elements within the galaxy.
     The observations reveal that these lines are greatly shifted
along the spectrum, or reddened, more than those of any galaxy
previously observed.  This red-shift phenomena is attributed to
the fact that the universe is expanding, thus these galaxies are
moving away from the Earth.  Because the universe is expanding at
a uniform rate, the more distant a galaxy, the greater its red
shift.  This phenomenon can be used by astronomers as a measure
of distance.

     Chambers, Miley and van Breugel also discovered that
distant, high red-shift galaxies have mysterious properties.
Unlike nearby "normal" galaxies, say the researchers, the visible
light in distant radio galaxies appears to be stretched out along
the direction of their radio emissions.

     Although this effect is not yet fully understood, it
indicates a very close relationship between the starlight
presumed to be producing the optical radiation and the powerful
radio emissions.  The radio emissions may be produced by twin
jets of extremely fast particles which are spewed out from a
massive black hole rotating at the core of the galaxy.

     The most likely reason the visible images of galaxies like
4C41.17 are stretched along the directions of their radio
emissions is that the high velocity jets of particles, which
produce the radio radiation, also compress gas and dust along
their paths, triggering new star formations.  The new stars then
preferentially would be born along the jets' paths, creating the
elongated optical appearance seen in 4C41.17.

     During the last few years, several attempts have been made
to draw conclusions about the evolution of the universe by
assuming that distant radio galaxies have similarities with
nearby galaxies.  The unexpected discovery of the strange
elongated appearance, associated with extremely distant radio
galaxies, forces astronomers to rethink some of their previous
deductions.

     Galaxy 4C41.17 also provides an important clue in
determining when galaxies were formed, a question that has
intrigued astrophysicists.  The researchers say that their
discovery establishes conclusively that, in contrast to some
theories, galaxies were forming only a few billion years after
the Big Bang.

     This research was supported by NASA, ESA, the National
Science Foundation, the Hopkins Ultraviolet Telescope project,
and the Space Telescope Science Institute.

     The Space Telescope Science Institute is operated for NASA
under a contract with the Goddard Space Flight Center, Greenbelt,
Md., by the Association of Universities for Research in
Astronomy, Inc. (AURA).  AURA is located on the Johns Hopkins
University campus in Baltimore.

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

Date: 8 Aug 88 16:02:23 GMT
From: [e-mail]  (Mike Smithwick)
Subject: Re: 95% vs. 99.9% reliability

In article <[e-mail]> [e-mail] (Keith Rogers) writes:
>
>I just don't see why they have to spend more than
>two years without a single flight, missing many important launch windows
>for various projects, just to have an all temperature space shuttle,
>when they could have just flown it on a warm day in almost perfect safety.
>
>Keith Rogers

Right after the event, NASA did announce that they intended to go ahead
with Crippin's Vandenburg launch in June of '86 since the SRBs were of
a different design and so couldn't suffer the same failure. Plus, the
warmer West coast weather would also ease problems. But we all know
what happened to those plans, don't we. . .

Remember though, that the Accident Review Board came up with a list
of "Criticality 1" problems which were fixable during the downtime. So,
I imagine that they simply decided that it wouldn't be wise to risk another
failure from another problem which could be repaired.



--
               *** mike (starship janitor) smithwick ***
"Due to the Writer's Guild of Amierica strike, this signature is
 temporarily cancelled".
[disclaimer : nope, I don't work for NASA, I take full blame for my ideas]

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

Date: 8 Aug 88 19:07:52 GMT
From: concertina![e-mail]  (Steve Hix)
Subject: Re: Satellites

In article <[e-mail]>, [e-mail] (Henry Spencer) writes:
> In article <[e-mail]> [e-mail] (Steve Hix) writes:
> >Pioneer 6    12/16/65 US    (still returning good data)
> >Pioneer 7    8/16/66  US    (still active)
> >Pioneer 8    12/13/67 US    (still active)
>
> You missed Pioneer 9, which is also still active.

Oops!  (See below)

> And I think one of the
> earlier ones -- Pioneer 8? -- is out of contact and presumed dead, as of
> quite recently.

My list, unfortunately, doesn't cover events after December 29, '87.

> You also missed Pioneers 10 and 11, heading out of the solar system.

Also two Mariners, as pointed out in another message.

Thanks for the corrections (from various sources) to the list I
originally sent out.  The errors, btw, are my fault:  The list I
was getting the info from has all the correct entries.

This is what comes of trying to scan through 2,979 launches during
lunch. :}

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

Date:     Mon, 08 Aug 88 14:04:30 -0900
Reply-To: <[e-mail]>
Sender: <[e-mail]>
From: Robert Jesse Hale III            <[e-mail]>

   I have been appointed representive of ISECCo for Space digest.  If you have
any questions, comments or suggestions please send them to me not to the
digest unless you decide it is worthy of the nets attention.  If I don't
reply to you within a week we are having a problem with the net.  Then if you
choose to use space digest to contact me.  At times the net looses an issue
or two,  please be persistant.     Robert J. Hale III

I am not an elected member, only a representive of a "people" space intrest
group.




                         SPACE:  Do you want to go?

     The  International Space Exploration & Colonization Co.  (ISECCo) is  an
organization  dedicated to the greatest effort mankind has  ever  undertaken:
extra-terrestrial  emigration.  Join us on the forefront of science and  help
us explore and ultimately settle the cosmos.

     ISECCo is developing space technology with the aim of reducing the  cost
of  getting  to, and surviving in, space.  We are  building  an  ecologically
sealed  unit  capable  of  supporting 2 people.  This  biosphere  will  be  a
prototype  for  self-contained  lunar  and  interplanetary  colonies.   Other
projects  include research and development of launch systems,  both  material
and human.

     The  ecologically sealed unit, or biosphere, has already  been  designed
and  construction  will begin in 1989.  Aerospace plane  concepts  are  being
studied  and  once an acceptable design has been selected, a  working  scaled
prototype will be built for air-launch.  Sub-orbital flight will test  design
parameters  and demonstrate concept viability.  Mass drivers are  also  being
considered  for use to launch material from terrestrial and  lunar  surfaces.
Research  in robotics, remote sensing, video communication,  and  space-based
power  stations is expected to begin early in the next decade.    Methods  of
making  space  colonies financially independent are  being  evaluated.   This
includes space manufacturing, satellite service and repair, space hotels, and
space mementos.

     Generous  donations from our members are our current source  of  income.
Future  funding  will be supplemented through venture  capital,  grants,  and
companies wishing to operate in space.

     Space  colonies  are  feasible  with  today's  technology.    Tomorrow's
technology  will  make  them economically viable.  Help us  turn  today  into
tomorrow and come with us on the ultimate journey: Come with us to the stars!

     For more information send your address to:
          U.S. mail:                         Bitnet:
               ISECCo                          FNRJH@ALASKA
               P.O. Box 60885
               Fairbanks, AK 99706

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

Date:         Mon, 08 Aug 88 19:37:20 CST
From: "SKott L. Underwood" <[e-mail]>
Subject:      August shower.

I have heard that there is an upcoming meteor shower
visible sometime in August here in the U.S.  If any-
body has any info on this event, please respond  via
SPACE or e-mail.
                     --- SKott (UCPL040 at UNLVM)

P.S. I will be in the Rockies  later this month  and
     would  like to know the dates and areas of  the
     sky to be observing.

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

Date: Mon, 8 Aug 88 21:36:22 EDT
From: [e-mail] (Paul F. Dietz)
Subject: Electromagnetic Launchers

I was thinking a little more about that scheme I described for
launching from Earth-based electromagnetic launchers.  A major
problem with the scheme was that a fixed launcher sends payloads
into different orbits depending on the time of launch.  This
complicates rendezvous with a LEO space station, for example.

But you can change orbital parameters without rockets, by exploiting
the nonsphericity of the Earth.  The plane of orbits can precess
(nodal regression) and the major axis of eccentric orbits can be made
to rotate (apsidal rotation).

Here's an updated scheme for launching mass to a space station in LEO:

  (1) An EML shoots a payload into a highly eccentric orbit with the
     same inclination as the station's orbit.  A small burn at apogee
     raises the perigee into the upper atmosphere.

  (2) Aerobraking lowers the apogee to several thousand miles.
     A small burn at apogee raises the perigee above the atmosphere.

  (3) The difference in nodal regression rates between the orbit
    of the space station and the payload matches the planes of the
    orbits.  This might take several weeks.

  (4) When the planes are matched, the payload aerobrakes further
   and enters a low phase matching orbit.  Rendezvous.

This should remove restrictions on the orbit of LEO space stations
that could be supplied by this scheme.

    Paul F. Dietz
    [e-mail]

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

Date: 8 Aug 88 21:46:48 GMT
From: a![e-mail]  (Jay Wooten)
Subject: Re: 95% vs. 99.9% reliability

In article <[e-mail]>, [e-mail] (Keith Rogers) writes:
>     Sure the O ring thing had to be fixed, but did it have to kill
> the entire U.S. space program in the meantime?

You can bet the Soviets would have hardly missed a beat in sending up
another one (something they've proved several times in the past).

Isn't it interesting that the space "program" of the (once) pioneering
leader has become so hamstrung by politics and public/media pressure not
to fail, while the otherwise world leader in repressive bureaucracy plods
ahead unflinchingly to world leadership in space.

       ~ Round the decay of that colossal wreck, boundless and bare ~
       ~ The lone and level sands stretch far away................. ~
       Jay Wooten  Los Alamos National Lab  ARPA: [e-mail]

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

Date: 9 Aug 88 02:38:48 GMT
From: [e-mail]  (Eugene Miya)
Subject: Re: Satellites

In article <[e-mail]> [e-mail] (Bill Turner) writes:
>> [Text of satellite list deleted]
>
>Isn't it a bit depressing that a deep scientific mission hasn't
>been launched by the US since 78?
>
>--Bill Turner

Your are telling me? 8-)  It's extremely depressing! 8-(
But, you the American public wanted "men" in space.  [Just stating
the facts (all those cards and letters).]
You see what is depressing is knowing the (or thinking about
the original proposed dates for Missions, largely killed,
by Ronnie and friends [Ed Meese who came to Caltech one fateful
date in 1981]).  You see I think of Galileo as a 1982 launch (when
my friends were doing ODs [orbit determinations], you
might think of it as 1989 or what ever.  Frank at JPL thinks of it
as a 1978 launch, and he proposed the Mission!  [Think how depressed
he would be [he isn't]].  Even worse are the single Solar/Polar mission
(rather than tandem), and the total lack of a comet rendezvous.
There were other missions cancelled as well.

Another gross generalization from

--eugene miya, NASA Ames Research Center, [e-mail]
  resident cynic at the Rock of Ages Home for Retired Hackers:
  "Mailers?! HA!", "If my mail does not reach you, please accept my apology."
  {uunet,hplabs,ncar,decwrl,allegra,tektronix}!ames!aurora!eugene
  "Send mail, avoid follow-ups.  If enough, I'll summarize."
Gee, lots of SDI postings: remember Star Wars is a trademark of Lucasfilm, Ltd.

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

End of SPACE Digest V8 #327
*******************