PLEASE NOTE:
*
CCNet DEBATE: CHANGING SWORDS INTO SPACESHIPS
From Ian Crawford <iac@star.ucl.ac.uk>
I am astonished by several statements in Andrew Glikson's
'Thought for
the Day', but most of all by his assertion that
"Resources are limited - the $$$trillions required
for space
colonization are the very same $$$trillions required for
attempted
restoration of the terrestrial environment. These are also
the same
$$$trillions required to feed and alleviate the suffering
of billions
of already living human beings"
The $$$trillions required for space colonization are infact the
$$$trillions (actually about $1 trillion pa) currently soaked up
by the
military sector of the world economy. A transfer of these
resources to
space development would satisfy the same economic vested
interests in
the aerospace companies, but would be ethically preferable. In
fact,
space development would only require a fairly small fraction of
the
global military budget (say 10%) -- freeing the rest for
ethically
desirable developmental projects here on Earth.
Only when, and if, all the global military budgets have been
converted
to peaceable global developmental projects will it become
legitimate to
criticise the much smaller amounts spent on space development.
Should anyone be interested, I have developed these ideas in more
detail in the "Disarming for the future: changing swords
into
spaceships" (New Scientist, 19 May 1990, pp. 67-68), and
more recently
in Space Policy, 11, 219-225 (1995).
Ian Crawford,
UCL
*
CCNet DIGEST, 13 January 1999
-----------------------------
THOUGHT OF
THE DAY
From Tom
Gehrels <tgehrels@LPL.Arizona.EDU>
We should
keep in mind that e-mail is easily done, without
the lag of
mailing a letter or the benefit of a two-way
talk.
A quick
way to remind us of that e-mail weakness is to
understand
it as h-mail, where the h stands for hurt.
This may
help us to hold it down.
With
Cheers!
Tom
Gehrels
-------------------------------------------------------
(1) ALASKAN EARTHQUAKE TRIGGERED BY ATMOSPHERIC IMPACT?
Joe Rao <Skywayinc@aol.com>
(2) SPACE FRONTIER FOUNDATION FORMS NEO-WATCH COMMITTEE
E.P. Grondine <epgrondine@hotmail.com>
(3) MUSES CN ASTEROID SAMPLE RETURN AND ROVER MISSION PROGRESSES
Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
(4) ASTEROID B-612: "GROWN-UPS ARE LIKE THAT...THEY ARE NO
LONGER
INTERESTED IN ANYTHING BUT FIGURES....."
Bernd Pauli <bernd.pauli@lehrer1.rz.uni-karlsruhe.de>
(5) DEEP SPACE 1 MISSION UPDATE
Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
(6) SEARCHING FOR LIFE ON OTHER PLANETS WITH PLASTIC TELESCOPES
Andrew Yee <ayee@nova.astro.utoronto.ca>
wrote:
(7) THE INTERNET TURNS 30
Andrew Yee <ayee@nova.astro.utoronto.ca>
======================================
(1) ALASKAN EARTHQUAKE TRIGGERED BY ATMOSPHERIC IMPACT?
From Joe Rao <Skywayinc@aol.com>
Anchorage Daily
Tuesday, January 12, 1999
Meteor image lasting
Quake after flash stirred confusion
By PETER PORCO
Daily News reporter
Those lucky enough to have seen the streak of light in the sky
that
turned into an incandescent flash and felt its earth-shaking boom
over Southcentral Alaska Friday say they'll never forget it.
What scientists have since judged to have been a
larger-than-usual
meteor burning up as it bored through the atmosphere lit up Tom
Habecker's windshield as well as his fancy.
"The thing is burned on my retina," said Habecker, a
ranger at Denali
National Park and an astronomy buff. The light that blazed at
about
10:20 p.m. Friday "was the biggest thing I've ever seen in
the night
sky."
"You could feel it traveling through the house," said
Candice Bales,
a lawyer who lives in Palmer and felt the boom but never saw the
light. "It came from the Sutton area, as fast as it traveled
through
the house. We felt it with our feet."
No trace of the object is known to have been found, Alaska State
Troopers said. Military authorities said no plane or missile or
cannon fire was involved. And contrary to rumors, the Parks
Highway
was never shut down because of falling debris, the state
Department
of Transportation said.
Mystery and curiosity, however, surrounded the light and the boom
that followed the flash by three or four minutes.
Enough people called authorities Friday night to express concern
that
state troopers took a helicopter up to Mount McKinley the next
day to
search for a possible area of impact.
The flight Saturday arose partly out of a confusion with another
real
event - an earthquake that struck the McKinley area about 50
minutes
after the flash-boom. The small temblor, registering 2.5 on the
Richter scale, occurred at 11:14 p.m. Friday and was centered 45
miles northwest of Talkeetna, said geophysicistBruce Turner with
the
Tsunami Warning Center in Palmer.
Among the first calls into the center Friday night was from a
worker
with the state emergency services office,Turner said. The worker
said
the agency was getting lots of phone calls. He gave the warning
center an approximate time of the boom as between 10 and 11 p.m.,
Turner said.
Turner went to the office and found records of the 11:14 p.m.
quake
at McKinley.
The emergency services worker felt state troopers should
investigate.
So on Saturday, two troopers picked up Denali's South District
ranger
and flew into the area but found nothing, said Jane Tranel, a
park
spokeswoman.
Enough witnesses have reported seeing the flash of light that
some
general idea of its trajectory - streaking mostly westward over
the
Palmer-Wasilla area - can be guessed.
Habecker was in his car with another ranger and their wives,
driving
home to the park after a basketball game in Healy. They were
headingsouth on the Parks Highway less than a mile from the park
entrance, where the highway drops away in front and the view
opens
up.
Through the windshield, the sky erupted with light.
"The core was orange, bright orange, and in my mind I still
see
sparks coming off of it," Habecker recalled. "Behind
the bright white
tail was a long iridescent green-blue tail. It was the most
beautiful
green I've ever seen, like a hot gas green."
The object appeared low in the sky to the south and was streaking
left to right, or generally westward, for about five seconds,
Habecker said.
Witnesses in Anchorage reported seeing the object toward the
north,
about halfway up the sky, streaking more or less southeast to
northwest.
The Tsunami Warning Center reported that two seismometers - one
in
Palmer and one in Sutton - recorded imprints at 10:22 p.m. from
some
explosive event. The one in Sutton recorded it 20 seconds
earlier,
said Tom Sokolowski, the center's director.
* Reporter Peter Porco can be reached at pporco@adn.co
Copyright 1999, Anchorage Daily
=======================
(2) SPACE FRONTIER FOUNDATION FORMS NEO-WATCH COMMITTEE
From E.P. Grondine <epgrondine@hotmail.com>
From SPACE FRONT: The Quarterly Journal of the Space Frontier
Foundation
Volume 6, Number 2 Fall 1998
No Chicken Littles
by Richard Godwin
Even paranoids have enemies. And sometimes Chicken Little is
right:
the sky really is falling. Eventually.
Somewhere out there in the vastness of space, something big and
very
dangerous is heading towards our fragile planet. The scientific
evidence is in: the notion of a large comet or asteroid colliding
with
Earth is not only real, it's a mathematical certainty. It has
happened
before, it will happen again, and it could mean the extinction of
our
kind, along with most of the other species on Earth.
Events such as the Shoemaker-Levy 9 comet impacts on Jupiter,
Hollywood
disaster films and various reports of near misses of the Earth
and Moon
by asteroids are at last awakening the public and policy leaders
to
this issue. These media events and the attention they have
focused on
the threat posed by Near Earth Objects (NEOS) have pointed out
the lack
of any cohesive international policies in this area.
It has also become apparent that although some small amounts of
funding
are trickling down from governments to support this work, the
funds are
minimal, often politicized in their disbursement, usually limited
to
those observers in the funding nation, and spent in the wrong
areas of
the process.
Clearly, support must be increased for those around the world who
search our skies to find, characterize and track these objects.
The
Watch Project was created to address these concerns.
Its primary goals are:
- To form a core group of the top experts in the field that
can act in
an advisory capacity to the media, entertainment
field and
governments.
- To increase the non-governmental funds available to
astronomers
involved in the search for NEO's via new private
sector initiatives.
- To disburse these funds impartially based on input from
those actually
in the field and doing the work.
- To begin planning concepts for what might need to be done
should
such Earth-threatening objects be discovered.
- To broaden the public discussion about NEOs to include
the promise
offered by these objects in the form of their
recourses, and given
the growing interest in their utilization, how they
might best and
safely be explored and used for the benefit of the
people of Earth.
- To develop means for amateurs to effectively participate
in the search
for NEOs
The Watch Council is intended to become the world's most
important body
of expertise in these areas of concern, and thereby to influence
the
perceptions of the public and policy makers when discussing NEOS,
the
levels and type of support required when applying government
funds to
NEO investigations, and to act as an independent voice in
upcoming
debates on their exploration and utilization.
To that end, we have begun assembling a Blue Ribbon team of
exactly
those people now seen as leaders in this field. Since we
are planning
to advise both media and governments, we have focused our
membership on
those not employed by governments.
Although we recognize that several of the world's top
participants in
the field are thus excluded from formal participation, we intend
on
working closely and consulting often with these important members
of
the community.
Currently The Watch Council includes:
- Richard P. Binzel: Professor in the Dept. of Earth, Atmospheric
and
Planetary sciences at MIT, a leading authority on the
spectra and
compositions of the near Earth and Belt asteroids.
- Dr.. Tom Gehrels: Professor of Planetary Sciences at the
University of
Arizona, the father and leader of the Spacewatch asteroid
search
programm, which pioneered the use of CCD imaging and
real-time
computer analysis to increase discovery rates of NEOS.
- Dr. Eleanor Helin: renowned astronomer affiliated with Jet
Propulsion
Laboratory, and for many years a pioneer in the discovery
of NEOS.
- Dr. John Lewis: University of Arizona, Professor of Planetary
Sciences and Co-Director of the Space Engineering Research
Centre,
U of Arizona. Author of 150 research publications as
well as the
popular science books, "Rain of Iron & Ice"
and "Mining The Sky."
- Laurel L. Wilkening: Authority on comets and meteorites and
editor of
the major research volume "Comets", has served
as Provost of the
University of Washington and chancellor of the University
of
California at Irvine. She was a member of The
National Commission on
Space.
The Watch was started with a grant of $50,000 provided by the
Foundation for the International Non-governmental Development of
Space
(FINDS).
======================
(3) MUSES CN ASTEROID SAMPLE RETURN AND ROVER MISSION PROGRESSES
From Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
From The "JPL Universe"
January 8, 1999
MUSES CN Progresses
By MARY BETH MURRILL
NASA and Japan's space science organization ISAS signed an
interim
agreement formally establishing the collaboration on the MUSES C
sample return and rover mission to an asteroid. Last year, the
announcement of opportunity for the MUSES CN science team was
released and proposals were received.
In the area of nanorover and spacecraft engineering, the project
tested the ISAS-developed heat shield materials at NASA's Ames
Research Center. The engineering models of the motors for the
MUSES
CN nanorover were delivered to JPL. The rover is about half way
finished with its detailed design, said Project Manager Ross
Jones.
In addition, he said, the electronic boards for the software
development model rover were completed.
JPL and The Planetary Society signed a memorandum of
understanding
establishing the society as an outreach partner with MUSES CN.
======================
(4) ASTEROID B-612: "GROWN-UPS ARE LIKE THAT...THEY ARE NO
LONGER
INTERESTED IN ANYTHING BUT FIGURES....."
From Bernd Pauli <bernd.pauli@lehrer1.rz.uni-karlsruhe.de>
For everybody to enjoy and contemplate - The Little Prince,
chapter 4:
I had thus learned a second fact of great importance: this was
that
the planet the little prince came from was scarcely any larger
than a
house!
But that did not really surprise me much. I knew very well that
in
addition to the great planets - such as the Earth, Jupiter, Mars,
Venus - to which we have given names, there are also
hundreds of
others, some of which are so small that one has a hard time
seeing
them through the telescope. When an astronomer discovers one of
these
he does not give it a name, but only a number. He might call it,
for
example, "Asteroid 325."
I have serious reason to believe that the planet from which the
little
prince came is the asteroid known as B-612. This asteroid has
only
once been seen through the telescope. That was by a Turkish
astronomer, in 1909. On making his discovery, the astronomer had
presented it to the International Astronomical Congress, in a
great
demonstration. But he was in Turkish costume, and so nobody would
believe what he said. Grown-ups are like that...
Fortunately, however, for the reputation of Asteroid B-612, a
Turkish
dictator made a law that his subjects, under pain of death,
should
change to European costume. So in 1920 the astronomer gave his
demonstration all over again, dressed with impressive style and
elegance. And this time everybody accepted his report.
If I have told you these details about the asteroid, and made a
note
of its number for you, it is on account of the grown-ups and
their
ways. When you tell them that you have made a new friend, they
never
ask you any questions about essential matters. They never say to
you,
"What does his voice sound like? What games does he love
best? Does
he collect butterflies?" Instead, they demand: "How old
is he? How
many brothers has he? How much does he weigh? How much money does
his
father make?" Only from these figures do they think they
have learned
anything about him.
If you were to say to the grown-ups: "I saw a beautiful
house made of
rosy brick, with geraniums in the windows and doves on the
roof,"
they would not be able to get any idea of that house at all. You
would have to say to them: "I saw a house that cost $
20,000." Then
they would exclaim: "Oh, what a pretty house that is!"
Just so, you might say to them: "The proof that the little
prince
existed is that he was charming, that he laughed, and that he was
looking for a sheep. If anybody wants a sheep, that is a proof
that
he exists." And what good would it do to tell them that?
They would
shrug their shoulders, and treat you like a child. But if you
said to
them: "The planet he came from is Asteroid B-612," then
they would be
convinced, and leave you in peace from their questions.
They are like that. One must not hold it against them. Children
should always show great forbearance toward grown-up people.
But certainly, for us who understand life, figures are a matter
of
indifference. I should have liked to begin this story in the
fashion
of the fairy-tales. I should have liked to say: "Once upon a
time
there was a little prince who lived on a planet that was scarcely
any
bigger than himself, and who had need of a sheep..."
To those who understand life, that would have given a much
greater air
of truth to my story. For I do not want any one to read my book
carelessly. I have suffered too much grief in setting down these
memories. Six years have already passed since my friend went away
from me, with his sheep. If I try to describe him here, it is to
make
sure that I shall not forget him. To forget a friend is sad. Not
every one has had a friend. And if I forget him, I may become
like
the grown-ups who are no longer interested in anything but
figures...
It is for that purpose, again, that I have bought a box of paints
and
some pencils. It is hard to take up drawing again at my age, when
I
have never made any pictures except those of the boa constrictor
from
the outside and the boa constrictor from the inside, since I was
six.
I shall certainly try to make my portraits as true to life as
possible. But I am not at all sure of success. One drawing goes
along
all right, and another has no resemblance to its subject. I make
some
errors, too, in the little prince's height: in one place he is
too
tall and in another too short. And I feel some doubts about the
color
of his costume. So I fumble along as best I can, now good, now
bad,
and I hope generally fair-to-middling.
In certain more important details I shall make mistakes, also.
But
that is something that will not be my fault. My friend never
explained anything to me. He thought, perhaps, that I was like
himself. But I, alas, do not know how to see sheep through the
walls
of boxes. Perhaps I am a little like the grown-ups. I have had to
grow old.
(Antoine de Saint-Exupéry, Le Petit Prince, 1943)
=================
(5) DEEP SPACE 1 MISSION UPDATE
From Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109 TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov
Deep Space 1 Mission Status
January 12, 1999
During the past three weeks, Deep Space 1 has exercised its
autonomous navigation system, an advanced science instrument that
studies space plasma and a radio system that transmits at an
unusually high frequency. In addition, the spacecraft has
continued
to its ion propulsion system and advanced solar array.
The operations team turned the ion propulsion system off December
18
to turn the spacecraft's helm over to the autonomous navigation
system, known as AutoNav. This system, one of the 12 technologies
that Deep Space 1 is validating, is designed to find the
spacecraft's
location in the solar system by taking images of known asteroids
and
comparing their positions to background stars. Because the
autonomous
navigation system knows where the asteroids are and where the
more
distant stars are, it can determine where it is in the solar
system
when the picture is taken.
AutoNav transitioned into spacecraft control by directing the ion
propulsion system to pressurize its xenon tanks for thrusting,
commanding the spacecraft's attitude control system to turn the
spacecraft to thrust in the direction that AutoNav desired and,
finally, starting the thruster.
AutoNav determines how much power to devote to the ion propulsion
system, which uses electricity to ionize and accelerate xenon. To
do
this, AutoNav has knowledge of how much power the advanced solar
arrays can produce and how much power the spacecraft consumes
apart
from the ion propulsion system. The spacecraft will consume more
power as it ventures farther from the Sun because it will need to
operate its heaters more.
When the ion propulsion system is thrusting, AutoNav updates both
the
direction and the throttle level for the thrusting every 12 hours
in
order to follow the flight profile stored on board. So far the
AutoNav system has operated flawlessly.
On December 21, thrusting was suspended for a few hours, during
which
AutoNav commanded the spacecraft to turn to point its camera at
asteroids and stars and take images of them. The images
taken are
allowing AutoNav's designers to improve onboard computer routines
for
processing such pictures. Previously, all they had was prelaunch
predictions of the camera's performance; now, with actual images,
the
routines can be updated. The successful demonstrations of
AutoNav's
control over the ion propulsion and attitude control systems and
the
camera are another step in transferring many of the
responsibilities
normally fulfilled by human controllers to intelligent spacecraft
of the future.
A skeleton team monitored the spacecraft over the holidays, with
the
ion propulsion system powered on.
On Tuesday, January 5, AutoNav turned off the ion engine,
completing
the first thrust segment of the Deep Space 1 mission. During that
period, the engine accumulated over 850 operating hours and
experienced 59 recycles, which are momentary automatic
interruptions,
or shutoffs, of the system, primarily for the system to protect
itself from damage due to drifting particulates. By contrast, in
the
first 850 hours of ground testing of the flight-spare ion
thruster
ion engine, approximately 240 recycles were experienced. The
lower
number of recycles in flight is an indication that in-space
operation of an ion thruster is more benign than operation in a
vacuum chamber. During the entire thrusting period, the power
processor and the xenon propellant storage/control systems have
worked just as designed.
On Wednesday, January 6, the Plasma Experiment for Planetary
Exploration (PEPE) was turned back on, and new software for the
advanced science instrument was tested. On Friday, January 8, it
was turned to its highest data rate so that it and a plasma
instrument on the Saturn-bound Cassini spacecraft could make
simultaneous observations of the solar wind. Those observations
continued over the weekend.
On Thursday, January 7, AutoNav again commanded the spacecraft to
turn to point its camera at asteroids and stars and take images
of
them.
On Sunday night, January 10, Deep Space 1 participated with the
Deep
Space Network in a telecommunications experiment. Deep Space 1
transmitted to the Deep Space Network complex at Goldstone,
California, using a very small, lightweight amplifier made by
Lockheed-Martin for radio signals at a frequency about four times
higher than the current standard frequency used for deep-space
missions. This frequency band, called Ka-band, offers the
possibility
of sending more information with less power, important for future
small but capable spacecraft. These tests are helping the Deep
Space
Network develop the capability to receive Ka-band routinely for
future spacecraft.
Deep Space 1 is almost 45 times as far away as the Moon now. At
this
distance of more than 17 million kilometers (more than 10 million
miles), radio signals sent from Earth take nearly one minute to
reach
the spacecraft.
=========================
(6) SEARCHING FOR LIFE ON OTHER PLANETS WITH PLASTIC TELESCOPES
From Andrew Yee <ayee@nova.astro.utoronto.ca>
wrote:
News Services
University of Arizona
Contact(s):
J. Roger Angel, 520-621-6541, rangel@as.arizona.edu
Neville J. Woolf, 520-621-3234, nwoolf@as.arizona.edu
James H. Burge, 520-626-7356, jburge@as.arizona.edu
January 9, 1999
Astronomers propose searching for life on other planets with a
plastic
telescope
By Mark Sincell
Two decades from now, astronomers may look for life on other
planets
using a telescope made of several sheets of reflective plastic in
orbit around the Earth.
At least, that's the idea that Roger Angel, a professor at The
University of Arizona's Steward Observatory, and co-workers
Neville
Woolf and James Burge, also of Steward Observatory, are
presenting at
today's meeting of the American Astronomical Society in Austin,
Texas. Glass or metal telescopes large enough to make the first
detection of life on planets outside our solar system are
planned,
but switching to lighter and cheaper plastic may be a crucial
step
towards a more detailed study of our extra-terrestrial neighbors.
The search for definitive evidence of life on planets orbiting
other
stars, called exoplanets, has become one of NASA's primary
objectives. A primary goal of the Space Interferometry Mission
(SIM),
an orbiting telescope scheduled for launch in 2003, is to search
for
exoplanets. SIM is unlikely to detect planets travel out past
Jupiter's orbit with the goal of finding Earth-like planets and
searching them for signs of life.
Angel sees his proposed telescope as the next step on the path.
"PlanetFinder will give us a good first shot at finding
evidence for
life," says Angel, "but to study planets transformed by
life, fecund
life, you really need a larger telescope." The envisioned
orbiting
plastic telescope would have a total light collecting area of
about
1,000 square meters.
But those expecting the new telescope to deliver snapshots of
smiling
extra-terrestrials on vacation will be disappointed. Angel's team
estimates that even crudely resolved images of exoplanets would
require an array of mirrors with a collecting area equivalent to
a
one kilometer diameter mirror, over a hundred times larger than
the
8-meter primary mirror that will be used in the Next Generation
Space
Telescope (NGST).
Instead, astronomers plan to look for features in the exoplanets'
thermal radiation spectrum left by oxygen and methane in the
planet's
atmosphere. Greenhouse gases such as oxygen and methane are a
direct
product of all the biological processes occurring on the Earth's
surface. Although these molecules are common in the Earth's
atmosphere, they are actually very unstable in combination and,
if
there were no life on Earth, they would rapidly combine. Finding
evidence for both molecules is "the killer test" for
life on other
planets, says Angel.
Even with a large telescope, gathering enough light from the
planet,
and then separating it from the light radiated by the planet's
own
sun, is a formidable task. To accomplish this feat,
planet-hunters
plan to use a technique called interferometry, in which the light
from the planet and its sun is reflected off different mirrors,
forming two or more separate beams of light. These beams are then
directed to a single detector where they are added up so that the
light waves from the star cancel out and only the light from the
planet remains.
The most straightforward way to perform space interferometry is
to
put several telescopes in orbit and combine their light. However,
to
detect exoplanetary greenhouse gases, each of these telescopes
would
have to be comparable in size to the NGST. Building and flying
several copies of the NGST would be prohibitively expensive.
The idea proposed by Angel, Woolf, and Burge is to replace all
but
one of the telescopes with flat plastic mirrors, each about 10
meters
square. The plastic reflecting surface is attached to a metal
frame
at several points that can be adjusted independently to preserve
the
planarity of the membrane.
Since the plastic mirrors are flat, they are relatively easy to
build
and maintain. "The main difficulty with curved mirrors is
making them
curved," says Angel, "Nature wants plastic to be
flat." And
micrometeorites, which periodically crash into satellites, pass
right
through the plastic.
To form the complete telescope, the plastic membrane mirrors are
distributed in space over 100 meters apart, approximately 1
kilometer
away from a central 10-meter space telescope, similar in design
to
the NGST. Light from the exoplanet is reflected off of the
plastic
mirrors and into the central telescope, where the different beams
are
"interfered" to remove the light from the star.
"We can correct for
the missing curvature of the flat mirrors inside the one
telescope,
in the same way that the optics in the Hubble Space Telescope
were
fixed", says Angel.
There are two main challenges to be met before plastic
interferometric telescopes start scanning our cosmic
neighborhood.
First, the plastic surfaces have to be extremely smooth and
uniform
in thickness so that they reflect light very accurately. Learning
how
to manufacture plastic of such high smoothnesses will take
"a lot of
work", warns Angel.
Then, once the plastic is smooth, the entire array of mirrors,
including the central telescope, must be kept in place, either by
mounting the mirrors on a rigid carbon composite truss or by
attaching small ion propulsion rockets to individual,
free-flying,
mirrors. Assembling and deploying such a network requires
technology
beyond that needed for even NGST.
Ultimately, how accurate will this telescope's design be? As a
comparison, in recent demonstrations at The University of Arizona
and
the Jet Propulsion Laboratory in Pasadena, Calif., the light from
two
lasers has been made to cancel to one part in ten thousand. To
remove
the light from the star and observe the spectrum of a nearby
planet,
the light from the star must be canceled to one part in ten
million.
And it will all be done in a telescope orbiting thousands of
miles
from the Earth.
=================
(7) THE INTERNET TURNS 30
From Andrew Yee <ayee@nova.astro.utoronto.ca>
University of California-Los Angeles
Contact: David Brown, dbrown@ea.ucla.edu
(310) 206-0540
January 7, 1999
Internet turns 30
This year marks the 30th anniversary of the birth of the Internet
at
UCLA
It was on the UCLA campus in 1969 that the first Internet
connection
was established, ushering in a new method of communication that
today
spans the globe and touches the lives of millions worldwide.
The federal government chose UCLA to become the first node of
what
was then known as the ARPANET because the faculty included
Professor
Leonard Kleinrock, whose research into "packet
switching" provided
the technological foundation upon which the network was to be
built.
The ARPANET -- which later became the Internet -- was funded by
the
Advanced Research Projects Agency (ARPA), created in 1958 to
support
scientific research in the United States. Its creation was
prompted
by the Soviet Union's success in placing the "Sputnik"
satellite in
space.
ARPA had been supporting a number of computer scientists around
the
country in the 1960s. As each new researcher was added, ARPA had
to
provide him with a computer, and each researcher asked for all
the
special capabilities that existed in the many unique computers
that
ARPA was supporting. By connecting the existing computers
together
via a data network, ARPA officials reasoned, the community of
scientists would be able to gain access to the special features
of
all those specialized computers.
The first network switch, known as an Interface Message Processor
(IMP), arrived at UCLA on the Labor Day weekend 1969. The UCLA
team
led by Kleinrock had to connect the first host computer to the
IMP.
This was a challenging task since no such connection had ever
been
attempted before. However, by the end of that first day, bits
began
moving between the UCLA computer and the IMP. By the next day,
researchers had messages moving between the machines.
"Little did those pioneers realize what they had
created," Kleinrock
said, reflecting upon history. "In fact, most of the
ARPA-supported
researchers were opposed to joining the network for fear that it
would enable outsiders to load down their 'private'
computers," he
added.
By December 1969, four sites were connected: UCLA, Stanford
Research
Institute, UC Santa Barbara and the University of Utah. UCLA was
in
charge of conducting a series of extensive tests to debug the
network. Under Kleinrock's supervision, UCLA served for many
years as
the ARPANET Network Measurement Center.
In one ambitious experiment during the mid-1970s, researchers at
UCLA
were able to control a geosynchronous satellite hovering over the
Atlantic Ocean by sending messages through the network from
California to an East Coast satellite dish.
Ten nodes spanning the United States had been connected by the
summer
of 1970. Kleinrock noted that the Cambridge-based computer
company
which designed the original IMP -- Bolt, Beranek and Newman (BBN)
--
never imagined there would be a need for more than 64 host
computers
in the network and provided only that number of connections.
Today,
of course, there are over 50 million computers attached to the
Internet -- and that number is expanding at a phenomenal rate;
moreover, traffic on the Internet doubles every 100 days.
Curiously enough, electronic mail (e-mail), which today is a
major
component of the network traffic, was an ad-hoc, add-on to the
network in those early days, Kleinrock said.
The ARPANET evolved into the Internet in the 1980s and was
discovered
by the commercial world toward the end of that decade. Originally
conceived and built by -- and for -- the scientific research
community, it is dominated today by the commercial sector.
"Indeed, no one in those early days predicted how enormously
successful and pervasive data networking would become,"
Kleinrock
said.
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