PLEASE NOTE:
*
CCNet 35/2002 - 15 March 2002
-----------------------------
"Here we meet the problem of communicating science and
distinguishing it from nonsense. As science cannot prove a
negative,
they could not say "it won't happen"; so they said
"it is exceedingly
unlikely". In the UK, someone summarised the report as
saying "the chance is
like me winning the lottery twice in succession". The
trouble is that the
vast numbers who buy lottery tickets regularly have such poor
feeling
for chance that they might regard two successive wins as decent
odds."
--Frank Close, The Guardian, 14 March 2002
(1) NASA'S NEW ASTEROID SENTRY STANDS WATCH
Space.com, 14 March 2002
(2) MUNICH RE WARNS OF METEOR THREAT
The Financial Times, 13 March 2002
(3) WHEN WORLDS COLLIDE
The Guardian, 14 February 2002
(4) EXPLODING STAR MAY (OR MAY NOT) HAVE SPARKED EARTH DISASTER
CNN, 11 March 2002
(5) PROSPECTS DIM FOR FOSSILS IN MARTIAN METEORITE
Sky & Telescope, 14 March 2002
(6) JOHN C POLKINGHORNE WINS 2002 TEMPLETON PRIZE
BBC News Online, 14 March 2002
(7) SPACEGUARD ON AUSTRALIAN TV THIS WEEKEND
Michael Paine < mpaine@tpgi.com.au
>
(8) GRAVITY ANOMALIES FROM SATELLITES
Hermann Burchard < burchar@mail.math.okstate.edu
>
============
(1) NASA'S NEW ASTEROID SENTRY STANDS WATCH
>From Space.com, 14 March 2002
http://www.space.com/scienceastronomy/solarsystem/asteroid_sentry_020314.html
By Robert Roy Britt
Senior Science Writer
NASA announced this week a new Web-based asteroid monitoring
system, called
Sentry, to monitor and assess the threat of space rocks that have
been
discovered have a chance of hitting Earth.
The setup is designed to help scientists better communicate with
each other
about the discoveries of new, potentially threatening asteroids
and the
follow-up observations that typically show those asteroids to be,
in fact,
no threat.
While no large asteroid is currently known to be on a collision
course with
our planet, experts say an eventual impact is inevitable and the
consequences could be grave, up to and including global
devastation that
might destroy civilization as we know it. The odds of such an
impact in any
given decade are extremely low, and most experts agree that there
would
likely be at least 10 years of warning if such an object were
ever spotted.
Smaller asteroids, however, are more likely to hit Earth in any
given year
and could cause significant local or regional damage. The odds
are low in
any given year. But over the course of a generation, the chances
of such an
event become significant.
The odds of a locally or regionally destructive asteroid hitting
an
inhabited area in a given 50-year period are about 1-in-160,
according to
experts.
False alarms
In recent years, asteroid experts around the globe have struggled
to develop
a system to catalogue and track newly spotted Near Earth
Asteroids -- those
that are close enough to Earth's orbit to warrant scrutiny -- and
to
properly communicate any possible threats to the public.
However, asteroids move so slowly against the background of stars
that when
one is first discovered, astronomers cannot pin down its exact
path.
Therefore, a wide range of possibilities are generated for the
rock's
possible orbit around the Sun, and often Earth becomes a possible
target in
those projected paths.
A handful of false alarms, in which scientists said there was a
remote
threat that a particular asteroid would hit Earth in a certain
year, have
made headlines and frightened the public. The first and most
notable was an
asteroid called 1997 XF11, which briefly loomed as a frightening
nemesis
until four years ago this week, when new observations revealed it
would miss
the planet.
A similar but less publicized "threat" emerged last
August with an asteroid
called 2001 PM10. Data on the rock was available on a public
website and was
hyped by uninformed web users before the fresh observations
removed the
risk.
Since the 1997 XF11 situation, researchers have argued, sometimes
vehemently, over how to better manage their data and make more
informative
public announcements.
The Sentry system
The new Sentry system, developed over the past two years, is
partly a
response to this perceived need. It is operated out of NASA's Jet
Propulsion
Laboratory. The system's online "Risks Page" included
37 asteroids as of
Thursday morning.
"Objects normally appear on the Risks Page because their
orbits can bring
them close to the Earth's orbit and the limited number of
available
observations do not yet allow their trajectories to be
well-enough defined,"
said JPL's Donald Yeomans, manager of NASA's Near-Earth Object
Program
Office, which oversees Sentry.
"By far the most likely outcome is that the object will
eventually be
removed as new observations become available, the object's orbit
is
improved, and its future motion is more tightly
constrained," Yeomans said
in a statement.
He added that several asteroids will be added to the list each
month, only
to be removed to another "no-risk" page soon afterward.
Sentry follows other attempts to deal with the publication of
asteroid risk
data. A color-coded disaster yardstick called the Torino Scale,
developed in
1999 and designed in part to inform the media and the public, has
gone
largely unused. On the Torino Scale, a zero or one represent
remote risk,
and a 10 means it's time to sell the farm.
All but one of the asteroids currently on the Sentry list are
zeros on the
Torino Scale. Topping the list, though, is a space rock named
2002 CU11,
discovered Feb. 7. It presently has a 1-in-100,000 chance of
hitting Earth
on Aug. 31, 2049. But as its orbit is refined, it is quite
possible that
this asteroid, like many before it, will be categorized harmless.
Big improvement
The Sentry system is similar to another online database, called
NEODys,
developed in recent years by asteroid experts in Italy.
Researchers from the
two systems are cooperating to cross check results in an effort
to make both
systems more effective, Yeomans said.
Sentry is "another big improvement" in the routine
monitoring of asteroids,
said Benny Peiser, who runs CCNet, a scholarly electronic
newsletter that
covers the threat of rocks from space.
Asteroid detections have rapidly increased in recent months, in
part because
NASA has a congressionally mandated goal to find 90 percent of
all Near
Earth Objects larger than 1 kilometer (0.6 miles) by 2008. About
500 of the
these asteroids have been found, and an estimated 500 or so
remain
undiscovered.
Sentry draws data each day from the Minor Planet Center in
Cambridge,
Massachusetts, where most data about asteroids is processed.
Sentry was
developed largely by Steve Chesley and Alan Chamberlin, with
technical help
from Paul Chodas.
The list of Sentry asteroids is available at
http://neo.jpl.nasa.gov/risk/.
Copyright 2002, Space.com
===============
(2) MUNICH RE WARNS OF METEOR THREAT
>From The Financial Times, 13 March 2002
http://news.ft.com/ft/gx.cgi/ftc?pagename=View&c=Article&cid=FT3ETZ6LRYC&live=true&tagid=FTDRYJRHFEC&subheading=insurance
By Tony Major in Frankfurt
Munich Re, the world's biggest reinsurer, on Wednesday urged
insurers "to
think the unthinkable" and examine seriously the threat of a
meteorite
impact on the earth.
In a warning reminiscent of a Hollywood science fiction
blockbuster, the
Munich-based group said a meteorite impact near a densely
populated area
could cause losses "of previously unknown dimensions".
It said insurers had to "rethink future loss potential"
following the
September 11 terrorist attacks and study the possible effects of
"bombardment from space".
British scientists concluded in a study two years ago that
meteorite strikes
could cause an explosion millions of times more powerful than an
atomic
bomb.
Munich Re said insurers were underestimating the risks of such a
catastrophe
which it admitted were still highly improbable.
But the terrorist attacks had created "a new dimension to
risk" that the
world's insurance industry had yet to fully appreciate, said
officials. "As
reinsurers we look at risks insurers have not yet realised,"
said Florian
Wost, a member of the company's geo-science research group.
"But insurers
will have to react in future."
In its natural catastrophe report for 2001, Munich Re says
insurers will
have to consider the "potential for maximum losses"
even if their
probability is low.
It argues that meteorite impacts, of which about 100 were
documented last
century, are capable of causing massive damage. Insurers
"would be liable to
cover the destructive results, such as explosions and
fires", says Munich
Re.
One of the best known events involved a 50 metre
"projectile" which came
down over Siberia in 1908.
"It exploded a few kilometres above the ground ...
flattening 2,200 sq km of
forest, equal to the size of Mexico City," says the report.
Munich Re concerns have been heightened by the losses it suffered
as a
result of the September attacks which revealed "a previously
unimaginable
risk potential". Its estimated losses of E2.1bn are the
biggest in its
history.
Copyright 2002, The Financial Times
================
(3) WHEN WORLDS COLLIDE
>From The Guardian, 14 February 2002
http://www.guardian.co.uk/science/story/0,3605,666783,00.html
When worlds collide: Scientists cannot definitively rule out
adverse
consequences of experiments, says Frank Close
All the rivers, lakes and oceans froze with a "great
vvarroomph", when Kurt
Vonnegut's mad scientist dropped some molecules of
"ice-nine" into a stream.
Ice-nine was a (hypothetical) form of water, more stable than the
ordinary
form, which froze at room temperature. In the story, Cat's
Cradle, ordinary
water is metastable and changes into the stable form - ice-nine -
when it
encounters minute traces of it.
Put ice-nine in a whisky and soda and you have instant scotch on
the rocks;
but don't drink it or the water in your body will instantly
freeze.
Thankfully, that is science fiction, but it is getting harder to
be sure
when one reads reports that scientists are concerned they might
inadvertently create a "killer plasma ready to devour the
Earth".
The story centres on experiments planned at two laboratories
involving high
energy accelerators of heavy ions. One, the Relativistic Heavy
Ion Collider
(RHIC), has just started in the United States, while a more
powerful version
is being built in Geneva - the Large Hadron Collider (LHC).
According to
some reports, scientists have warned that if these experiments
"go wrong"
they could produce a new form of particle, which the media has
named the
"killer strangelet".
Strangelets are atomic nuclei similar to those that make matter
as we know
it, but contaminated by "strange particles" such as
those found naturally in
cosmic rays. Whereas strange particles normally live for a
shorter time than
it takes to blink an eye, it is possible that in nuclei they
might
stabilise. The intriguing possibility is that under certain
conditions, the
strangelets might turn out to be more stable than the stuff we're
made of.
Were strangelets to come into contact with ordinary matter, they
might act
like ice-nine, gobbling up the nuclei of ordinary matter until
they became
so heavy that they sank to the centre of the Earth. Then they
would eat up
the Earth from the inside, "converting it into one giant
strangelet and
killing us all in the process". Could this happen?
On both continents, committees of scientists were convened to
look into this
and the more general question: what risks are there when entering
unknown
territory with high energy particle accelerators? Our experience
has given
us a picture of how the universe works, and based on the best
evidence we
proceed to plan the next steps. Although RHIC and the LHC will be
entering
new territory in our experience, it is not a first in the history
of the
universe. Scientists will be recreating conditions that existed
long ago,
within a split second of the Big Bang.
The universe has been there, and survived for 15 billion years.
Even today,
some particles in cosmic rays attain energies far in excess of
anything we
can imagine reproducing here. If such conditions could lead to
subatomic
ice-nine, they would most probably have done so already. All the
evidence is
that they have not. The scientists produced a compelling report.
Here we
meet the problem of communicating science and distinguishing it
from
nonsense. As science cannot prove a negative, they could not say
"it won't
happen"; so they said "it is exceedingly
unlikely".
In the UK, someone summarised the report as saying "the
chance is like me
winning the lottery twice in succession". The trouble is
that the vast
numbers who buy lottery tickets regularly have such poor feeling
for chance
that they might regard two successive wins as decent odds.
Contrast this with the chance of being hit by an asteroid - tiny,
but
someday it will happen - or with destroying our ecology, which is
happening.
But as for killer strangelets or destabilising the universe in
some way,
would any committee chairman have risked using language the
public
understands and said: "It won't happen?" After all, if
it is wrong, no one
would ever know!
Copyright 2002, The Guardian
MODERATOR'S NOTE: The media hype surrounding particle
accelerators is
described in a review paper together with various doomsday
scenarios that
are essentially ruled as unlikely; see DISASTER CAUSED BY HEAVY
ION
COLLISIONS AT RHIC? http://theory.gsi.de/~vanhees/publ/cup.pdf
================
(4) EXPLODING STAR MAY (OR MAY NOT) HAVE SPARKED EARTH DISASTER
>From CNN, 11 March 2002
http://europe.cnn.com/2002/TECH/space/03/10/supernova.disaster/index.html
By Richard Stenger, CNN
(CNN) -- Piecing together clues from astronomy, paleontology and
geology,
scientists have proposed that an ancient supernova may have
damaged the
protective ozone layer around the Earth and wreaked havoc on
terrestrial
life.
The researchers theorize that a group of young stars prone to
short,
cataclysmic lives passed relatively near our solar system several
million
years ago.
"Nobody had realized that this cluster of stars ... could
have been so close
to Earth during the (time)," says astronomer Narciso
Benitiez.
Along with his partner Jesus Maiz-Appellanis, Benitez dug around
in the
geologic record for evidence that one of the rogue stars
detonated with the
Earth in the blast zone.
"When I did a search, one of the first things that popped
out was a 1999
finding," Benitiez says. A team of German astronomers had
found an unusual
variety of iron in samples drilled from the Earth's crust below
the ocean
floor.
The Germans hypothesized that the iron isotope originated from a
supernova,
but knew of no suspect stars in our celestial neighborhood when
the strange
metal was thought to have dusted the planet, Benitez says.
But Maiz-Appellanis and Benitez did some detective work and came
up with the
likely culprit -- a volatile star pack known as the
Scorpius-Centaurus OB
Association, which passed relatively near the solar system
several million
years ago.
The Scorpius-Centaurus horde
A crucial break in the detective case came from a fortuitous
source,
Benitez's wife, microbiologist Matilde Canelles, whom Benitez
enlisted to
search the fossil record for clues.
Canelles found strong evidence that a catastrophe killed off a
large
population of marine organisms about two million years ago.
Her husband calculated that the Scorpius-Centaurus horde so was
close to the
Earth at the time, that if one of them had gone supernova, the
powerful
energy blast could have stripped away much of the ozone layer,
which
protects terrestrial life from harmful solar ultraviolet rays.
"This would have produced a significant reduction in
phytoplankton abundance
and biomass, with devastating effects on other marine
populations, such as
bivalves," Benitez says.
The scientists acknowledge that more study is necessary to
confirm their
theory. But if it proves correct, there's little to worry about
from
Scorpius-Centaurus.
The next member of the gang expected to go supernova is Antares,
which at
roughly 500 light-years away is too distant to rattle our planet,
they say.
Copyright 2002, CNN
=============
(5) PROSPECTS DIM FOR FOSSILS IN MARTIAN METEORITE
>From Sky & Telescope, 14 March 2002
http://skyandtelescope.com/news/current/article_534_1.asp
By David L. Chandler
March 14, 2002 | Ever since it was trumpeted at a hastily
convened press
conference in August 1996, the subject of possible signs of life
in the
Martian meteorite ALH 84001 has remained intensely controversial.
At the
time, David S. McKay (NASA/Johnson Space Center) and his
coauthors presented
four lines of evidence suggesting that the 4-billion-year-old
meteorite
contains chemical or fossil traces of microbial life. In the
years since,
however, these signs have been disputed by other researchers, who
ascribe
them either to terrestrial contamination or to nonbiological
processes on
ancient Mars.
To many, the strongest remaining evidence for Martian microbes is
the
presence of tiny, uniform, chemically pure crystals of magnetite
embedded in
globules of carbonate - crystals that look remarkably similar to
those
produced by certain strains of terrestrial bacteria. Kathie L.
Thomas-Keprta
(Lockheed Space Systems) and her colleagues have continued to
study the
crystals and strengthen their argument that the tiny grains
exhibit a suite
of five characteristics found in biogenic crystals and never seen
in
magnetite produced by chemical and geophysical processes.
Not anymore, say two teams who will report tomorrow that they
have
independently synthesized magnetite crystals in the laboratory
showing most
of these same characteristics. The presentations will be made at
the 33rd
Lunar and Planetary Science Conference in Houston, Texas. One
group, led by
Dadigamuwa C. Golden (Hernandez Engineering) and Douglas W. Ming
(NASA/Johnson), had previously produced perfectly formed,
chemically pure
magnetite crystals, thus matching two of the distinctive features
of those
in ALH 84001. Now, having completed 3-D examination of their
fabricated
crystals, Golden and Ming say these also share the distinctive
shapes
(termed truncated hexaoctahedrals).
Using a similar method, Andrea M. Koziol (University of Dayton,
Ohio) and
Adrian J. Brearley (University of New Mexico, Albuquerque) have
also
produced crystals that match the same nearly uniform size and
purity of
those found in the meteorite. But they have not yet been able to
study the
3-D shapes, a difficult process. Still, Koziol notes, the fact
that both
teams were able to subject carbonate globules to a
high-temperature pulse -
470° C. for 5 minutes - without altering them and without
introducing other
metals into the magnetite contradicts a key claim made by
Thomas-Keprta. "It
doesn't disprove" her overall claims, Koziol says, "but
it does show a
pretty nice alternative."
Allan H. Treiman (Lunar and Planetary Institute), who has grown
very
skeptical of the McKay group's claims, believes the new work will
mark a
turning point in the debate over ALH 84001. Of the original lines
of
evidence, he said, "The only one really standing at this
point is the
magnetite crystals. This will pretty much be the death
knell."
Still, the fossil proponents are far from throwing in the towel.
An
assessment led by Joseph L. Kirschvink (Caltech) concludes that
up to half
of the meteorite's magnetite grains are indeed truly biogenic.
Thomas-Keprta
will also be reporting new results Friday. Everett K. Gibson
(NASA/Johnson),
a member of the original McKay team, says that the other groups
subjected
their samples to conditions that ALH 84001 could never have
experienced,
which undermines the relevance of their results. But
Thomas-Keprta "is going
to present some data Friday that's going to knock the socks off
some
people," he said. "I think the argument stands stronger
now than when we
looked at it in '96."
Copyright 2002 Sky Publishing Corp.
=============
(6) JOHN C POLKINGHORNE WINS 2002 TEMPLETON PRIZE
>From BBC News Online, 14 March 2002
http://news.bbc.co.uk/hi/english/sci/tech/newsid_1872000/1872637.stm
John C Polkinghorne, an Anglican priest and former professor at
Cambridge
University, has won the 2002 Templeton Prize for progress in
religion.
A one-time fellow of the Royal Society, John Polkinghorne
specialised in
work on sub-atomic particles before entering the priesthood.
He said he wanted to take science and religion with great and
equal
seriousness, seeing them as complementary to each other and not
as rivals.
The prize is the world's most lucrative annual prize for an
individual,
earning the winner £700,000 ($1m).
Sub-atomic particles
Author of many books, Dr Polkinghorne has made his name applying
the same
rigorous scientific disciplines that he mastered as a
mathematical physicist
to the study of theology.
Many of these attempt to marry theology with science.
For instance he argues that evolution is not opposed to believing
in God,
but is a perfect fit with the concept of a God-given gift of
creation that
continues to be and to make itself.
He resigned as professor of Mathematical Physics in 1979, after
creating
mathematical models that predict the movement of sub-atomic
particles. These
calculations helped reveal the structure of matter.
He then entered the priesthood, becoming a parish priest before
returning to
Cambridge where he was president of Queens' College for three
years.
In 1997 he was knighted for distinguished service to science,
religion,
learning and medical ethics.
The announcement of this year's Templeton Prize comes at a time
of growing
interest in the relationship between science and religion.
In the US support for the theory of creationism to explain the
origins of
life is growing to the point were campaigners are trying to get
it added to
the school science curriculum alongside Darwin's theory of
evolution.
So it seems all the more appropriate that Dr Polkinghorne should
have been
recognised for his work in attempting to reconcile the study of
science and
faith.
Truth to be found
Dr Polkinghorne is known for saying that science and religion in
fact
complement each other and are not rivals.
"The most important thing they have in common is the belief
that there is a
truth to be sought and found -- a truth which comes through the
pursuit of
well-motivated belief."
The award is given each year for outstanding originality in
advancing the
world's understanding of God or spirituality.
The award is always set at an amount that exceeds the value of
the Nobels.
The first winner was Mother Teresa in 1973. Others include the
Rev Dr Billy
Graham (1982), Aleksandr Solzhenitsyn (1983), physicist Carl
Friedrich von
Weizsäcker (1989), and Benedictine monk and professor of
astrophysics
Stanley L. Jaki (1987).
Last year's recipient was the Rev. Canon Dr. Arthur Peacocke, an
ordained
Anglican priest, Oxford University faculty member and a
biochemist who
pioneered early research into DNA.
Two more of Dr Polkinghorne's books are due for publication later
this year:
The God of Hope and the End of the World, and Quantum Theory: A
very short
introduction.
He will receive the award from Prince Philip on 29 April at
Buckingham
Palace.
Copyright 2002, BBC
============================
* LETTERS TO THE MODERATOR *
============================
(7) SPACEGUARD ON AUSTRALIAN TV THIS WEEKEND
>From Michael Paine < mpaine@tpgi.com.au
>
Dear Benny
Your Australian subscribers might like to know that the letter to
the
Australian Government from more than 90 researchers has attracted
the
attention of two major TV networks. The letter was sent to Prime
Minister
John Howard and several Ministers at the end of January.
( http://www4.tpg.com.au/users/tps-seti/pr_oz_sg.htm
)
This Sunday (17th March) the issue will receive extensive
coverage on
Channel 7's Sunday Sunrise program (8am Sydney time) and Channel
9's 60
Minutes (7.30pm Sydney time). They include interviews with Paul
Davies and
Duncan Steel. Sunday Sunrise also interviewed Malcolm Walter and
myself at
the National Museum of Australia (Malcolm has organised an
excellent space
and bioastronomy exhibition there, including a section on impacts
developed
by John Gorter).
The discovery of 2002 CU11 is an interesting coincidence - an
800m diameter
Near Earth Asteroid that has been assigned a Torino Scale rating
of 1
("merits careful monitoring.").
regards
Michael Paine
=============
(8) GRAVITY ANOMALIES FROM SATELLITES
>From Hermann Burchard < burchar@mail.math.okstate.edu
>
Dear Benny,
as DIE WELT reported 3/13/02, a pair of polar orbiting satellites
named
GRACE will be launched by an international team headed by
Christoph Reigber,
GeoForschungsZentrum Potsdam, on a Russian carrier Saturday. The
satellites
will travel at a constant distance from each other for highest
accuracy in
determining gravity anomalies.
The launch will be transmitted live on the web:
http://www.live.dlr.de/grace
See the Potsdam Institute site:
http://www.gfz-potsdam.de
An earlier project launched a satellite CHAMP that according to
DIE WELT had
found a 500 km "oldest" crater in Angola.
Best regards,
Hermann
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*
BRIGHTNESS OF COMET IKEYA-ZHANG
>From Jonathan Shanklin < jdsh@bas.ac.uk
>
Interestingly the comet's behaviour can also be represented by a
simple
progressive brightening that is simply dependent on the time from
perihelion
and is independent of log r. At the moment this does not give
much
predictive information as some comets with this type of behaviour
continue
brightening after perihelion, whilst others begin to fade before.
An
optimistic estimate of brightening continuing for 10 days after
perihelion
would suggest that the comet could reach 2nd magnitude. The
current rate of
brightening is about 0.08 magnitudes per day, so that the
magnitude equation
becomes: m = 3.6 + 5 log d + 0.08 * abs (days from T) For March
14.5 this
would become 3.6 + 5*log(0.90) + 0.08*(18.9-14.5) = 3.7.
Alternatively the
traditional form of the equation is m = 6.7 + 5 log d + 9.3 log r
which
gives m = 3.8 for the same time. Both equations corrected for
aperture, so
giving the current naked eye brightness.
Regards,
Jonathan Shanklin
j.shanklin@bas.ac.uk
British Antarctic Survey, Cambridge, England
http://www.antarctica.ac.uk/met/jds
British Astronomical Association, Comet Section
http://www.ast.cam.ac.uk/~jds
=============
IKEYA-ZHANG
>From Mark Kidger < mrk@ll.iac.es
>
Jonathon raises an interesting point here. The apparent
brightness of a
comet depends on the instrument used to see it so two
astronomers, one using
the naked eye and another a telescope will not see the same
brightness.
Although it is called the aperture correction this is a
misconception as it
is really a "magnification correction" - the comet will
appear fainter with
an instrument that spreads its light out more than with one that
concentrates it, so the naked eye observer will see it brighter.
There is a standard aperture correction, but it really needs to
be derived
comet by comet as it depends on how concentrated the comet is.
For
Ikeya-Zhang I would have great doubts about it as the comet
started fairly
difuse and has become much more concentrated with time. This
means that a
single aperture correction is unlikely to be valid over the 6
weeks or so of
observations.
As the comet has got brighter and more condensed the standard
correction
will over-correct, thus possibly explaining the quite slow
brightening rate
found here (just about average for a comet of this kind).
In the end though it matters very little because the end result
is very much
the same either way... this will not be the magnitude 2 comet
that some
people were hoping and it will not get very much brighter than it
is now.
It's a pity. We'll just have to wait for 2004 and C/2001 Q4
(NEAT).
Mark