Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_2/V11_252.TXT

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Subject: SPACE Digest V11 #252

SPACE Digest                                     Volume 11 : Issue 252

Today's Topics:
            Re: release of images
NASA dedicates human performance lab at Ames Research Center (Forwarded)
             Space Report, Apr 10
              SEESAT source requested!!
            Re: release of images
           Re: TRAKSAT - satellite tracking program
       Re: Reports of Io's vulcanism before VOYAGER 1 ?
               Re: Interstellar travel
----------------------------------------------------------------------

Date: 11 Apr 90 22:14:01 GMT
From: usc!zaphod.mps.ohio-state.edu!rpi!crdgw1!ge-dab!puma!andrew.ATL.GE.COM![e-mail]  (John F Nixon)
Subject: Re: release of images

[e-mail] (Eugene Miya) writes:
>The Year lag was a controversial thing when it was instituted.
>Some people wanted THEIR data FOREVER.

I would note that there is still data from the "Dead Sea Scrolls" which has
not been made public (and this stuff was recovered beginning in 1947!!) for
similar reasons; the translators should have first crack at analysis.  Three
decades seems like enough time to me...

At least we'll get to see HST data after a year.  Are their any requirements
on data taken with, say, the Mayall scope to be released to the public after
a fixed period of time??

--

----
[e-mail]                    ...steinmetz!atl.decnet!jnxion

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

Date: 12 Apr 90 01:07:54 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: NASA dedicates human performance lab at Ames Research Center (Forwarded)

Mary Sandy
Headquarters, Washington, D.C.                    April 11, 1990

Donald G. James
Ames Research Center, Mountain View, Calif.


RELEASE:  90-53

NASA DEDICATES HUMAN PERFORMANCE LAB AT AMES RESEARCH CENTER


     NASA today unveiled its latest research laboratory designed
to answer fundamental questions about long-term human spaceflight
and to expand our knowledge of human factors in the nation's
increasingly crowded airspace system.

     The Human Performance Research Laboratory (HPRL) at NASA's
Ames Research Center, Mountain View, Calif., is the first U.S.
facility designed and built to study the human role in advanced
aviation and prolonged space travel.  Speaking at the dedication
ceremonies, Ames Center Director Dale Compton said that the HPRL
"will help scientists answer questions about the relationship
between humans and complex machinery.  Ambitious space goals,
like a lunar outpost, a Mars expedition or the National Aero-
Space Plane, depend on a better understanding of how humans will
interact with machines in these missions."

     Among the specialized laboratories and test facilities to be
included in the HPRL are those dedicated to development of
virtual environment workstations, computational vision and
advanced rotorcraft displays.  The HPRL also will contain a
unique design facility for the U.S. Army/NASA Aircrew-Aircraft
Integration program.

     Compton, together with special guests, also broke ground for
the new $8.6 million, 59,000 sq. ft. Automation Sciences Research
Facility (ASRF) in today's ceremonies.  The ASRF, scheduled for
completion in January 1992, will provide laboratories to conduct
research and technology development in automation and artificial
intelligence.

     Compton said, "the decision to locate the Automation
Sciences Research Facility and Human Performance Research
Laboratory in a single complex recognizes that artificial
intelligence (AI) and human factors research complement each
other.  A productive relationship between humans and machines is
critical in the aerospace program.  Forging the ultimate
relationship between people and computers depends on shared
research between AI scientists and human factors experts."

     One question these laboratories will address is how
humans will travel to Mars and return to Earth safely.  Mars
expeditions likely will depart from Space Station Freedom.
During the long trip to Mars, astronauts must rely more on
automated systems to make critical launch and mission operations
decisions.

     Complex mission objectives imposed by high technology
projects like the National Aero-Space Plane, Space Station
Freedom, a lunar outpost and Mars exploration require
computer-controlled systems that complement highly-trained
humans.  Specialized facilities in the HPRL and ASRF will greatly
enhance NASA's ability to develop and demonstrate computer
science technologies in artificial intelligence needed to support
the nation's aerospace endeavors.

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

Date: 10 Apr 90 13:43:26 GMT
From: frooz!cfa250![e-mail]  (Jonathan McDowell)
Subject: Space Report, Apr 10

Jonathan's Space Report

Apr 10, 1990 (no.34)
Fingers tightly crossed.....
----------------------------------------------------

The launch of orbiter Discovery and the Hubble Space Telescope
was scrubbed at T-4min on Apr 10 due to a problem with APU 1.
The APU (Auxiliary Power Unit) exhibited erratic behaviour during
startup. The launch may be attempted again on Apr 11.

Anatoli Solov'yov (Komandir) and Aleksandr Balandin (Bortinzhener)
continue in orbit aboard the Mir complex. The Soyuz TM-9 transport
and the Progress M-3 freighter are currently at the station.
Solov'yov and Balandin have been in space for 58 days.

The Pegasus winged rocket made its first flight on Apr 5, launched by
the NASA NB-52 over the Pacific Ocean.  NASA's Pegsat satellite was
successfully placed in orbit, together with the second DARPA Global Low
Orbiting Message Relay satellite.

Remember Westar VI? Challenger deployed it in Feb 1984, the Pam-D upper
stage failed and left it in low orbit.  Discovery retrieved it in Nov
84, and the insurance company sold it.  The satellite eventually ended
up as Asiasat 1, property of Asia Satellite Communications Co of Hong
Kong.  Asiasat 1 returned to orbit on Apr 7 aboard a Chinese Chang Zheng
3 launch vehicle.  This was the first Chinese launch of a non-Chinese
satellite, from Xichang Space Center.

Kosmos-2063, an early warning satellite, was launched on Mar 27.

Apr 12 will mark the 29th anniversary of the first human flight in
space by Yuriy Alekseevich Gagarin aboard the spaceship 'Vostok'.

(c) 1990 Jonathan McDowell

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

Date: 11 Apr 90 12:17:10 GMT
From: mcsun!hp4nl!nikhefh![e-mail]  (Greg Retzlaff)
Subject: SEESAT source requested!!

I am looking for a copy of the SEESAT code (or equivalent) that
will take the satellite orbital elements posted to the net and
supply predictions.  Many thanks to anyone that can help me out!

Greg Retzlaff
NIKHEF-K
Dutch Institute for Nuclear and Particle Physics
Amsterdam
--
Greg Retzlaff, NIKHEF-K
Netherlands Institute for Nuclear and Particle Physics
The most common things in the universe  | We are all in the gutter,
are hydrogen and stupidity.             | but some of us look at the stars.

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

Date: 12 Apr 90 01:59:52 GMT
From: haven!uvaarpa!murdoch!astsun.astro.Virginia.EDU![e-mail]  (Greg S. Hennessy)
Subject: Re: release of images

In article <[e-mail]> [e-mail] (John F Nixon) writes:
#At least we'll get to see HST data after a year.  Are their any requirements
#on data taken with, say, the Mayall scope to be released to the public after
#a fixed period of time??

I don't know what is written on paper, but in practice the only copy
of the data is what the astronomer takes with them when they leave the
peak. There is a real problem in archiving the amount of data
generated by a nights observing with a CCD. When Burbidge was in
charge, he would pester astronomers to send back the plates, or pay
for them. In theory the data does become public domain, but NOAO is
far too busy trying not to shut down telescopes to have the resources
to do anything about archvial. The national facilities, NRAO and NOAO
are now getting fewer dollars now than in 1984, which means that when
figured in constant dollars (for inflation) they have gotten a 30
percent budget cut. Ain't Reagan wonderful, not to mention Bloch.

-Greg Hennessy, University of Virginia
 USPS Mail:     Astronomy Department, Charlottesville, VA 22903-2475 USA
 Internet:      [e-mail]
 UUCP:        ...!uunet!virginia!gsh7w

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

Date: 10 Apr 90 19:06:47 GMT
From: mcsun!ukc!tcdcs!swift.cs.tcd.ie!ccvax.ucd.ie![e-mail]  (Gordon T Gopher at CCVAX)
Subject: Re: TRAKSAT - satellite tracking program

In article <[e-mail]>, [e-mail] (Brian Roberts) writes:
> Neat satellite tracking program available anonymous ftp
>
>          Paul E. Traufler
>          111 Emerald Dr.
>          Harvest, Al.  35749
>          205-726-5511 (work)
>          205-830-8450 (home)
>

- sounds neat all right Paul - any chance of getting hold of the source code ?
(OK so I'm paranoid (-| )

        Neil.


--------------------------------------------------------------------------------
Neil Conway [e-mail] | Disclaimer ? HA! I'll die of surprise if
            [e-mail] | this even makes it onto the net... :-)
--------------------------------------------------------------------------------

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

Date: 11 Apr 90 14:06:26 GMT
From: mcsun!ukc!edcastle![e-mail]  (Bob Gray)
Subject: Re: Reports of Io's vulcanism before VOYAGER 1 ?

In article <[e-mail]> [e-mail] (Daniel Fischer) writes:
>P.S.: What do you think - does Io or Triton deserve the title "strangest body
>in the solar system? As shown above, Io has a good reason to be active, but
>Triton...?

There is one body in the solar system that is away ahead of
anywhere else in terms of activity, peculiar chemical
reactions, and general strange behaviour.

It is that big lump of rock next to the little lump of rock
third out from the sun.
    Bob.

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

Date: 11 Apr 90 23:20:42 GMT
From: swrinde!cs.utexas.edu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca![e-mail]  (Christopher Neufeld)
Subject: Re: Interstellar travel

In article <[e-mail]> [e-mail] (Jeffrey Kirk Bennett) writes:
>[on the practicality of interstellar travel]
>
>1. The goal is to find intelligent life and/or a habitable planet. It
>seems to me that both are extremely
>    rare events. Though I've no doubt that there is life somewhere else
>in the universe, I'm sure it is
>    an exceedingly rare event.
>
   Maybe, maybe not. This is one of the things which we might find out
by sending automated probes to the stars.

>2. I don't see mankind inventing practical anti-matter propulsion or
>whatever the current idea is
>    in the next century or two.
>    One
>related question is- are there
>    thermodynamic efficiency considerations which limit the maximum
>possible speed? Would
>    these depend on the method of propulsion used?
>
   No thermodynamic constraints appear.

>    The point is, due to relativistic mechanics, wouldn't it be a 1-way
>trip? If you travelled to a
>     star 5 light-years away at .9c, wouldn't a few centuries or
>millenium pass on Earth?
>
   Certainly not. If you go 5 light years at 0.9 c, it will take 5.555
years in the Earth frame for you to complete the journey. In the ship's
frame, ignoring acceleration and deceleration time, it will take 2.42
years.

>How severe is the time dilation effect? Again, I'm not a physicist.
>What happens to time during
>     the acceleration and deceleration- when the velocity is not
>constant.
>
   To good approximation the instantaneous relativistic corrections for
constant velocity situations can be used here.

>     Does anyone know how to figure that all out
>realistically, including all the
>     non-constant terms.
>
   Yes.

>How long would a trip take at .1c, .5c and .9c
>in both ship's and Earth's
>     time?
>
   In the Earth's frame the time taken is just distance/velocity. In the
ship's frame this number is multiplied by the quantity sqrt(1-v^2/c^2).

>3. Assuming all the fuel is burned during the acceleration and
>deceleration phases, how would
>    the craft return?
>
   You can bet a lot of money that there will be a gas giant in the
solar system where you land. Such things will show up on the HST, and so
the aspiring traveler will know before leaving whether there is such an
entity. This is a good source of hydrogen, which can be reaction mass,
or fusion fuel, or energy source for an antimatter factory.

>4. Even if it had the fuel to return, how would it find the Earth again,
>since it is not exactly
>    standing still, and may have moved unpredictably due to passing
>stars, black holes, etc. in
>    the path of the Sun.
>
   Certainly not. Such unpredictable behavious is on the scale of
millions of years, not decades. Most easily, the Sun has to be one of
the stars in a certain range of distances (you know how far you've come)
and the spectral lines of the Sun would identify it unambiguously. Also,
the Earth is a prominent radio star which should be obvious several
solar systems away. Of course, this last fact may change as we begin to
pipe our signals through fiber optics to replace the "RADIATION" which
carries our radio and television signals.

   Personally, I am confident that humans will send manned slowships to
the stars within the next five hundred years, barring some sudden
disaster. Of course, if FTL shows up it could be much sooner. General
relativity makes so many contradictory statements on the subject of FTL
that there are actually a few different blueprints for FTL drives in the
scientific literature which are fully consistent with general
relativity. Don't bet that FTL will ever appear, though. I believe it
might, but there seems to be a deficiency in our present understanding
of the universe and causality.

>On a related note- can't we dismiss UFO reports out of hand? My
>reasoning is this:
>
>1. There are no little green men on the moon. Therefore, E.T.'s would
>have to come from
>    outside the solar system = other stars.
>
   Non sequitur. How about creatures floating in the atmospheres of the
gas giants, colonizers from other solar systems who live in the asteroid
belt (when you think about it, once you've arrived at another solar
system there seems little reason to drop yourself down a deep gravity
well), or half a dozen other possibilities.

>2. If something is coming from another star, it would have to have near
>light-speed travel.
>
   Why? What if they hibernated, or had naturally extended life spans,
or used generation ships, etc.

   Well, this has been fun....


--
 Christopher Neufeld....Just a graduate student  | "Like most
 [e-mail]              | intellectuals he is
 [e-mail]          Ad astra! | intensely stupid."
 "Don't edit reality for the sake of simplicity" |  Marquise de Merteuil

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

End of SPACE Digest V11 #252
*******************