PLEASE NOTE:
*
CCNet 133/2002 - 19 November 2002
--------------------------------
"If this black hole got within striking distance of Earth,
Mirabel
said via e-mail, "It could disrupt the solar system.
However, this one
will not come closer than 1,000 light- years in the next 200
million
years," he said. "The probability of a catastrophic
event on the Earth
from black holes moving at high speed is almost zero compared
with the
probability of a catastrophic event from asteroids or
comets."
--Reuters, 18 November 2002
"Eventually we will discover something. Society should start
planning for that unexpected but potentially tragic
possibility."
--David Morrison, The New York Times, 19 November 2002
"Few scientists are arguing that society should be
developing an
asteroid-deflection system, given the extremely low odds of an
impact
any time soon. "A major technological effort at this time is
probably ill
conceived because our children will be so much better at
it," said Dr.
Alan W. Harris of the Space Science Institute in Boulder, Colo.
--Henry Fountain, The New York Times, 19 November 2002
"Let us now do the groundwork for the yet unknown
environmental
challenge that will come some day in the form of a major impact.
If
we don't develop anything now, and we suddenly find something on
a
collision course with the Earth, our only choice will be to use
nuclear
weapons, with all the associated risks of blowing the object into
pieces or
not providing enough push. Therefore, it is important to test and
develop
something now."
--PROJECT B612 (David Morrison, Clark Chapman, et al.)
http://b612.boulder.swri.edu/
(1) ARMAGEDDON CAN WAIT: STOPPING KILLER ASTEROIDS
The New York Times, 19 November 2002
(2) DAZZLING DISPLAY: EARLY RESULTS OF THE LEONID METEOR SHOWER
Space.com, 19 November 2002
(3) TIS GREAT BRITISH CLIMATE: METEOR SHOWER HIDDEN BY CLOUD
BBC News Online, 19 November 2002
(4) UH-HUH: "RUNAWAY BLACK HOLE HEADING OUR WAY"
Houston Chronicle, 18 November 2002
(5) AND FINALLY: NAZIS ON SPEED WERE TOO SLOW
Ananova, 19 November 2002
==========
(1) ARMAGEDDON CAN WAIT: STOPPING KILLER ASTEROIDS
>From The New York Times, 19 November 2002
http://www.nytimes.com/2002/11/19/science/space/19ASTE.html?ex=1038373200&en=640e219104adc3ff&ei=5040&partner=MOREOVER
By HENRY FOUNTAIN
Sooner or later, it's bound to happen.
Sooner or later, scientists who study Earth-crossing asteroids
say,
astronomers will find one that has a significant chance of
striking the
planet.
Unlike several recently discovered asteroids that were first
given very long
odds for a collision, this time more precise orbital calculations
won't
eliminate the possibility. This one will be an asteroid
"with our name on
it," in the words of David Morrison, a scientist at the NASA
Ames Research
Center and one member of a small community of astronomers,
physicists,
engineers and other scientists who think a lot about such an
unthinkable
event.
It is not clear what would happen then, though Dr. Morrison and
others are
trying to awaken governments and the public to the need to at
least think
about developing a way to respond. "Eventually we will
discover something,"
Dr. Morrison said, though maybe not in this century or even this
millennium.
"Society should start planning for that unexpected but
potentially tragic
possibility."
But it is becoming clear that a longtime assumption of many
scientists - and
of Hollywood filmmakers - that a nuclear weapon is the best way
to save the
planet from a threatening asteroid is no longer in such favor.
Increasingly,
those scientists who study asteroid hazards say that a subtler,
quieter,
slower approach might be called for. These scientists are turning
T. S.
Eliot on his head: it's not that the world will end with a
whimper rather
than a bang, they say. It's that it may not end that way.
A nuclear detonation, some scientists say, could break the
asteroid into
several large pieces, increasing, rather than eliminating, the
threat. And a
blast some distance from an asteroid, designed to shove it into a
slightly
different orbit, might not work either; the asteroid might soak
up the
energy like a sponge. "I'd say forget that," said Dr.
Keith A. Holsapple, a
professor at the University of Washington who studies the effects
of
simulated nuclear explosions.
By contrast, most of the alternative approaches would build up
force
gradually, gently nudging, rather than shoving, the asteroid.
They would
rely on the same basic Newtonian principle - that for every
action there is
an equal and opposite reaction - only written small, with tiny
actions
creating tiny opposite reactions that, given enough time, could
shift an
asteroid's orbit enough to change a hit into a close call.
Among the approaches being talked about are some that have been
the stuff of
science fiction for years: a mass driver, a sort of
electromagnetic conveyor
belt that would be planted on an asteroid and hurl dirt from its
surface, or
a solar concentrator, a parabolic mirror that would orbit the
body and heat
up the surface, creating a plume of vaporized material.
Perhaps the most intriguing idea - and one that may not be as
far-fetched as
it sounds - has been put forth by Dr. Joseph Spitale, a scientist
at the
University of Arizona. To move an asteroid, he says, just change
its color.
This "paint it black" approach would change how much
sunlight it absorbs,
and how hot it gets. Heat radiating from an asteroid (in the form
of thermal
photons) creates a small force in the opposite direction - a
phenomenon
called the Yarkovsky effect, after I. O. Yarkovsky, a Russian
engineer who
first described it a century ago. Changing the amount of heat
would change
the force, affecting the orbit. The sun would move the asteroid,
one photon
at a time.
There are, of course, logistical problems with this and other
alternative
technologies - getting buckets of paint to an asteroid, for
instance, is no
sure (or inexpensive) thing. Many scientists acknowledge that in
some
circumstances a nuclear weapon may be the only option.
Few scientists are arguing that society should be developing an
asteroid-deflection system, given the extremely low odds of an
impact any
time soon. "A major technological effort at this time is
probably ill
conceived because our children will be so much better at
it," said Dr. Alan
W. Harris of the Space Science Institute in Boulder, Colo. [Oh
yes, and our
children's children will be even more advanced; given the odds,
they could
just as easily shift their responsibility onto the next
generations and so
on; BJP].
Rather, most scientists say that any money available should go
into
detecting asteroids and investigating them to better understand
the
potential threat.
Improvements in detecting and understanding asteroids, in fact,
are what is
prompting the change of thinking toward a slow approach, which
was
exemplified by presentations at a NASA-sponsored workshop on
asteroid
hazards in September near Washington that "pretty much sent
the nuclear
weapon idea home packing," said Dr. Erik Asphaug, a
professor at the
University of California at Santa Cruz and one of the workshop's
organizers.
There are several detection efforts under way, with a goal of
meeting a
Congressional mandate of finding 90 percent of objects larger
than a
kilometer in diameter by 2008. An asteroid of this size is
thought to strike
the Earth once every million years or so, but since it is capable
of
producing destruction on a regional scale or worse, in terms of
potential
loss of life over time it represents the biggest risk.
The best estimate is that there are perhaps 1,100 of these large
asteroids,
about half of which have been discovered and found to be
harmless. The odds
are extremely slight that any of the remaining large asteroids
will prove
threatening, either.
But any asteroid with a chance of hitting Earth would cross the
planet's
path many times before it actually hit, so it would probably be
detected
decades in advance.
There is no current detection program for smaller asteroids, of
which there
are perhaps half a million down to about 50 meters in diameter,
the smallest
size capable of penetrating Earth's atmosphere (and roughly the
size of one
that exploded over the Tunguska River in Siberia in 1908,
destroying forests
for hundreds of square miles). And there is no systematic survey
for
potentially hazardous comets, which come out of the astronomical
equivalent
of left field. "So we would either very likely have a lot of
warning or none
at all," said Dr. Clark Chapman of the Southwest Research
Institute in
Boulder.
No warning time means no options. A short amount, on the order of
a decade
or two, might leave a nuclear blast as the only choice. But with
many
decades of warning, there is room to investigate the asteroid
first by
sending a spacecraft to it, and then use a slow-acting method to
divert it,
one that wouldn't require launching a nuclear weapon. "We
would want to seek
out every alternative to a nuclear weapon before turning to that
technology,'` Dr. Chapman said.
What makes some of these alternatives promising is what
scientists have come
to understand about asteroids. Many of them, the scientists say,
are rather
loose agglomerations of stony fragments that have stuck together
over time
in the cosmic rock tumbler that is the solar system. They are not
giant
solid boulders. "Maybe something like a popcorn ball is a
better way to
describe it," Dr. Holsapple said.
Such porous objects would be hard to obliterate or move with a
nuclear
blast, even one some distance from the surface, he said.
"But pushing a
little bit for a long time would work equally well whether an
asteroid is
porous or not," he added.
Porosity might prove to be a problem even for some of the
alternative
methods, however. A mass driver, for instance, would have to be
firmly
attached to an asteroid in order to work, as would a small rocket
engine,
another proposed method. It might not be possible to anchor such
equipment
to a popcorn-ball asteroid.
Dr. Spitale's idea would get around that problem, but it would
not be
without other difficulties. For one thing, a lot of paint would
be required.
(He has also suggested dumping a thin layer of dirt on the
asteroid to
change its color, and has estimated that dozens of rocket loads
would be
needed.) For another, because they are so small, asteroids have
very little
gravity, so it is unclear that paint or dirt would stay in place.
One
solution to that problem and to the problem of transporting large
amounts of
material, he says, would be to pepper an asteroid with small
explosives, to
remove the top layer and expose material that might have
different thermal
characteristics.
While generally saluting this kind of outside-the-box thinking,
some other
asteroid experts find Dr. Spitale's ideas largely impractical.
"I guess I
consider that approach kind of quirky," Dr. Chapman said.
"I'll be the first to confess that this isn't the last word
in asteroid
hazard mitigation," Dr. Spitale said. Still, he added, while
it may not be
easy, along with the nuclear option it is the only approach that
appears
technically feasible at this time. "If we were faced with
the problem
today," he said, "this is one of maybe two approaches
where we could say,
`Well, we could do this.' "
Copyright 2002, The New York Times
========
(2) DAZZLING DISPLAY: EARLY RESULTS OF THE LEONID METEOR SHOWER
>From Space.com, 19 November 2002
http://www.space.com/spacewatch/leonids_results_021119.html
By Robert Roy Britt
Senior Science Writer
posted: 07:00 am ET
PHILADELPHIA - Early this cold November morning the Leonid meteor
shower
wowed skywatchers as intoxicating blurs of light streaked in from
space.
Even under city lights, the Leonids put on a dazzling display,
though some
observers expressed disappointment over dim shooting stars and a
show that
was not as impressive as last year, when a spectacular storm may
have left
some folks jaded. Reactions seemed to be mixed also based on
local viewing
conditions.
In the suburbs of this city, 16 shooting stars graced a patch of
sky -
roughly 30 percent of the entire sky and surrounded by trees -
during one
5-minute period. A rough projection indicates that during the
peak of
activity, between 5:30 and 5:45 a.m. EST, an hourly rate of more
than 400
shooting stars should have been visible to an observer with a
view of the
entire sky. Skywatchers in rural eastern locations should have
seen even
higher rates.
The peak was forecast to occur at 5:30 a.m. EST and astronomers
had expected
hourly rates to approach or exceed 600 for rural areas. Many
residents of
the East, where the show was expected to be at its best, combated
thin haze
or in some cases thick cloud cover.
Brewster LaMacchia, watching the show from the Boston area,
counted 50
meteors between 4:30 and 5 a.m. under partly cloudy skies. An
observer in
Granbury, Texas reported spotting at least six a minute around 5
a.m. local
time.
Alan MacRobert, an editor with Sky & Telescope magazine,
watched a few
"earthgrazing" meteors late Monday night.
"These were long, slow streamers sailing up to 40 degrees
across the sky
(since they were just skimming the upper atmosphere nearly
horizontally),"
MacRobert wrote on Meteorobs, an electronic meteor observation
list. He said
he saw "not quite one a minute from 11:20 to 11:32."
Other observers on a SPACE.com message board gave glowing
reports, one
calling it the "best shower I've ever seen." Though
some observers reported
seeing bright fireballs, this year's storm seemed generally to be
lacking in
these impressive, super-bright meteors compared to previous
years.
As many as 75 percent of the shooting stars that would normally
have been
visible were outshone by the Moon, astronomers had predicted
before the
event.
More reports are expected later this morning. A full analysis of
the
spectacle won't be completed for days. Europeans were to see a
good show,
forecasters had said, while North Americans were thought to have
the best
seats.
The Leonids occur every November, when Earth passes through a
complex
network of dust streams laid down by a comet called
Tempel-Tuttle. The comet
rounds the Sun every 33 years, and on each pass through the inner
solar
system it leaves a fresh stream of particles in a slightly
different
location.
Over centuries and millennia, these streams all spread out,
mingling and
creating a giant river of stuff ranging in size from sand grains
to marbles.
In normal years, Leonid meteor rates top out at a few dozen per
hour, or
near one per minute. Only when our planet travels through a dense
stream put
down relatively recently can storms like this year's occur.
This morning, Earth waded into the middle of streams that
Tempel-Tuttle had
deposited in 1767 and 1866. The older stream was to generate a
peak of
activity over Europe at around 0400 UT. The newer stream fueled
the more
active North American peak, which astronomers had expected for
about 5:30
a.m. EST. Other bits of debris that had been drifting through
space for
thousands of years also contributed to the show.
Timing dictated that people in Asia and the Southern Hemisphere
were not
well positioned for this year's grand displays.
No significant Leonid storms are expected again until at least
2033. Another
major storm won't likely occur until at least 2098. Meanwhile,
the Perseid
meteor shower, an annual August event, could kick up to storm
level in the
year 2028.
This year's Leonid display will tail off quickly now. Only a
sprinkle of
shooting stars will be visible each hour between midnight and
dawn
Wednesday. The next chance to see a nice meteor shower will be on
Dec. 14,
when the annual Geminids are expected to put on a fine display.
Editor's Note: This story will be updated later today as results
roll in.
Copyright 2002, Space.com
=============
(3) TIS GREAT BRITISH CLIMATE: METEOR SHOWER HIDDEN BY CLOUD
>From BBC News Online, 19 November 2002
http://news.bbc.co.uk/1/hi/sci/tech/2491343.stm
Cloud, fog and mist across Europe hampered the view of the Leonid
Shower,
which peaked in the early hours of this morning.
This year's meteor shower was expected to be one of the most
spectacular to
be seen over the next thirty years, but bad weather left many sky
watchers
disappointed.
The "shooting stars" may still be seen in the Unites
States - where the peak
of the shower starts at 1030 GMT.
If there had been clear skies, astronomers predicted seeing up to
a 1000
meteors an hour.
Grains of rice
The shooting stars are actually particles from comet
Tempel-Tuttle which has
a 33-year orbit around the Sun.
As the Earth passes through the cloud of dust left by the comet,
these
particles burn up in the atmosphere, creating the light streaks.
Most of the meteors are no bigger than a grain of rice.
They enter the Earth's atmosphere at speeds of 40 mph (70 km),
burning up
and producing the shooting stars we see from the ground.
Spoilt view
In some European countries the view was hampered by thick fog.
Some weather reports said visibility was down to less than 50 m.
In North America the burst started at 1030 GMT (0530 EST or 0230
PST).
Bille Cooke, a meteor forecaster from the US space agency's
(Nasa) Marshall
Space Flight Center, said: "Try and get away from city
lights; the darker
the sky, the more meteors you'll see."
There is no guarantee that the shower will appear on cue.
But for those who missed the shower it will be possible to view
it online on
Nasa TV.
Copyright 2002, BBC
==============
(4) UH-HUH: "RUNAWAY BLACK HOLE HEADING OUR WAY"
>From Houston Chronicle, 18 November 2002
http://www.chron.com/cs/CDA/story.hts/space/1666691
Reuters News Services
WASHINGTON - A runaway black hole is streaking through the Milky
Way galaxy,
dragging an aging star along to snack on as it heads in Earth's
general
direction, astronomers reported today.
There is absolutely no need to panic, though: The black hole will
get no
closer to our solar system than 1,000 light-years, and that will
not happen
for 200 million years or so. Right now it is between 6,000 and
9,000
light-years away.
A light-year is about 6 trillion miles, the distance light
travels in a
year.
Still, astronomers using the Hubble Space Telescope to track the
black hole
are excited about it, because it gives them the best evidence yet
that it
was created when a star several times the mass of our sun blew up
in a vast
explosion known as a supernova.
Black holes are voracious matter-sucking drains in space that
exert so much
gravitational force that nothing, not even light, can escape
their pull.
While black holes themselves cannot be seen, they can be detected
by the
characteristic swirl of material falling into them.
In this case, the Hubble telescope's sharp sight has enabled it
to see the
black hole's companion star, which it is gradually gobbling as it
hurtles
through the galaxy.
Most black holes tend to stay put, often at the center of
galaxies,
including our own Milky Way.
But Felix Mirabel, of the French Atomic Energy Commission and the
Institute
for Astronomy and Space Physics/Conicet of Argentina, said this
is only the
second black hole found to be moving at high speed.
Mirabel said he and his colleagues detected another one that was
moving even
faster, and reported on it more than a year ago, but the
scientific report
was published on Sept. 13, 2001, two days after hijack attacks at
the World
Trade Center and the Pentagon, and was largely ignored by the
general media.
"Its speed indicates that the black hole must have been
formed in a
supernova explosion," Mirabel said in answer to e-mailed
questions.
Scientists have known for decades that black holes come in a
variety of
sizes, from supermassive -- with the weight of millions or even
billions of
suns -- to the much lighter stellar-mass, which is what this
runaway object
is.
Known to astronomers as GRO J1655-40, the mobile black hole is
not just
strolling through the plane of the Milky Way. It is rocketing
through at
250,000 miles an hour, four times faster than the stars in its
galactic
neighborhood.
Scientists have been using the Hubble orbiting telescope to watch
this one
since 1995 and were able to measure how far it had come when more
images
were made in 2001.
The only way such a black hole could form would be the implosion
of the core
of a star when it dies, Hubble scientists said in a statement.
The implosion
sends out a shock wave that rips apart the rest of the star.
The black hole's companion star, which revolves around it every
2.6 days,
managed to survive the explosion only to spend its declining days
being
nibbled to death.
If this black hole got within striking distance of Earth, Mirabel
said via
e-mail, "It could disrupt the solar system.
"However, this one will not come closer than 1,000
light-years in the next
200 million years," he said. "The probability of a
catastrophic event on the
Earth from black holes moving at high speed is almost zero
compared with the
probability of a catastrophic event from asteroids or
comets."
Copyright 2002, Reuters
============
(5) AND FINALLY: NAZIS ON SPEED WERE TOO SLOW
>From Ananova, 19 November 2002
http://www.ananova.com/news/story/sm_711650.html?menu=news.scienceanddiscovery.amazingscience
Nazis on speed - new report says drug could have changed history
Nazi scientists were on the verge of developing a powerful
version of speed
that could have swung the war in their favour, according to a new
report.
Historian Wolf Kemper says the drug contained cocaine and other
stimulants
and was tested on concentration camp victims.
Codenamed D-IX by Nazi scientists, it was intended to help German
soldiers
fight with almost unlimited endurance towards the end of the war.
Respected Hamburg historian and criminologist Wolf Kemper, whose
report is
entitled Nazis on Speed - Drugs in the Third Reich, says it was
tested on
prisoners at the Sachsenhausen camp, near Berlin.
Concentration camp inmate Odd Nansen told Kemper he witnessed 18
inmates
each carrying backpacks weighing 20 kilograms being forced to
march in a
circle.
He said they had to cover a distance of up to 90 kilometres
without a break
and were known in the camp as "the pill patrol".
Nansen wrote in his diary: "At the beginning members of the
penal commando
sang and whistled, but after the initial 24 hours most of them
had
collapsed."
Kemper says the drug had been developed by a research team led by
a Kiel
pharmacologist on the orders of Adolf Hitler's headquarters in
Berlin.
It was given to inmates at Sachsenhausen, in November 1944 but
the planned
large-scale production of the drug was prevented by the Allies'
victory.
If it had gone ahead six months earlier, it could have made the
crucial
difference in motivating Hitler's demoralised and weakened front
line
forces, the report speculates.
Copyright 2002, Ananova
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