PLEASE NOTE:
*
LETTERS TO THE MODERATOR, 12 January 2000
-----------------------------------------
(1) THE SCOTMAN DEBATE: UK SPACEGUARD TASK FORCE
Graham Richard Pointer <grp1@st-andrews.ac.uk>
(2) AFP ERRORS
Duncan Steel <D.I.Steel@salford.ac.uk>
(3) RETRACTION
Victor Noto <vnn2@kua.net>
(4) WARNING TIMES & PLANETARY DEFENSE
Robert Clements <Robert.Clements@dva.gov.au>
(5) UNPARALLELED OPPORTUNITIES
Jens Kieffer-Olsen <dstdba@post4.tele.dk>
(6) SIMULATING ARMAGEDDON ON YOUR PC
Michael Paine <mpaine@tpgi.com.au>
(7) FOSSILS & THE K-T BOUNDARY
Bob Johnson <bob_johnson@talk21.com>
(8) SUN - A HEAVY IMPACTOR
Timo Niroma <timo.niroma@tilmari.pp.fi>
==================
(1) THE SCOTMAN DEBATE: UK SPACEGUARD TASK FORCE
From Graham Richard Pointer <grp1@st-andrews.ac.uk>
Dear Dr Peiser,
"The Scotsman" has an on-line discussion about Lord
Sainsbury's
asteroid taskforce. It's at
http://www.scotsman.com/taf/newsforum.taf
Graham Pointer.
===================
(2) AFP ERRORS
From Duncan Steel <D.I.Steel@salford.ac.uk>
Dear Benny,
Of course essentially all press reports contain errors, and
anyone with
expertise in some area is familiar with the inaccuracies which
creep in
to such reports. Just a couple from the recent AFP report:
>Dozens of observatories around the world now scour the skies
nightly
>for any threat from space.
This is true if you count all those backyard telescopes. But the
real
work is being done by just three or four brilliant search
programmes,
and they are *not* "scouring the skies nightly". What
they are doing is
scouring a few percent of the sky monthly.
>Each day, several thousand tonnes of cosmic debris fall to
Earth, says
>Jean-Eudes Arlot, director of the Institute of Celestial
Mechanics at
>the Paris Observatory.
Actually the terrestrial influx of small (below 1 ton masses)
extraterrestrial material averages to about 100 tonnes per day:
see the
paper by Love and Brownlee in Science, 1993. The long-term
average
influx of mass may well come out to be rather higher than this if
one
takes into account the very largest objects hitting the Earth
(i.e.,
asteroids and comets). But "each day" it's about 100
tonnes, although
variable during the year.
Cheers,
Duncan Steel
===============
(3) RETRACTION
From Victor Noto <vnn2@kua.net>
Dear Benny
I would like to make a retraction to you and your readers of my
statement made in reply printed in LETTERS TO THE MODERATOR,
11/01/2000 which follows - "I personally think there is not
the
will or time and man will go the way of the dinosaur."
I was wrong to make this pessimistic statement and I now feel
there is
the will and time to detect, prevent and/or defend against a dino
killer extinction asteroid event because such an impact is a
very, very
low probability event to happen within the next few hundred
years. I
do, however, feel that no one knows for sure just how unlucky
humanity
can be and reserve the right to change back again should the
extinction
impact event occur. Let's face facts: death comes to all who live
long
enough and extinction of earth species is the rule not the
exception.
99% of all species that have ever existed on earth has gone
extinct at
some point. Some people feel that just because we have brains
that make
us aware of what's happening and the environment around us, we
are the
exception to this extinction rule. We may escape this asteroid
and
comet peril and go on for a very long time or not but I doubt
very much
that the species man as he exist on earth will go on forever.
Call me a
pessimist or a fatalist but to me I think the species man is
finite and
will end much like the earth, sun, the milky Way and this
universe has
a beginning and end.
Victor D. Noto
=================
(4) WARNING TIMES & PLANETARY DEFENSE
From Robert Clements <Robert.Clements@dva.gov.au>
In this context, i note that all the potential impact scenarios
analysed to date have been rocker cannon affairs: a relatively
close
flyby of Earth at the wrong time & place results in an actual
impact
situation further down the track, sometimes after one or more
additional sweeps through terrestrial space.
Granted that a direct hit from cow corner can never be completely
ruled
out, the more completely we sweep the skies, the more likely it
is
we'll be able to obtain realistic advance warning for even a
small
impactor by catching it on a preimpact approach. Even better: if
the
impact scenario involves additional Earth flybys, we may even be
able
to use the body's regular proximity as a lever to change its
orbital
trajectory.
It's difficult to believe that warning about a flyby in 5 years'
time
which results in an impact 12 years later couldn't be used to
develop
at least some form of mitigation strategy; whether that be
evacuation
of the impact area or re/deaccelleration of the imapcting
body....
All the best,
Robert Clements <Robert.Clements@dva.gov.au>
====================
(5) UNPARALLELED OPPORTUNITIES
From Jens Kieffer-Olsen <dstdba@post4.tele.dk>
Michael Paine for Explorezone: [snip] "The Near
Earth Object (NEO)
population constitutes both an unprecedented hazard
and an
unparalleled opportunity," Lewis says. "It
is sometimes said that
there is a fine line that separates a threat from an
opportunity.
The near-Earth asteroids present us with just this
dilemma. They
present us with an intelligence test of the highest
order, with the
highest possible stakes for the human race."
Dear Benny,
I find that our forum may be giving too much emphasis to the
threatening aspect of NEOs, and too little to that of
'unparalleled
opportunity'.
There is nothing wrong about conjuring up doomsday scenarios, as
long
as we don't preach to the converted. Once in agreement about the
cold,
nasty facts of the potential threat, let's examine whether in
fact our
cause to save mankind is much better furthered by tableing
scientific
facts about the golden opportunities waiting to be grabbed by
shrewd
politicians and private investors.
In particular, the search for NEOs should also be aimed at
identifying
orbital characteristics, which make capture into Earth orbit more
or
less feasible. Somewhat similar to the Torino Scale a rating
should be
established, which takes into consideration the cost, complexity,
and
timeframe of a nudging operation, plus the projected value of the
object delivered to GEO (or other orbit). For a few decades
this
rating would have mostly academical value, since the prospect of
a
successful enterprise would be low. However, a level of awareness
would
emerge enabling governments ( and private business ) to
immediately
identify an 'unparalleled opportunity' coming up. Then, if space
technology is judged worthy of the mammoth investment, mankind
will
surely go for the 'big catch', rather than waste an opportunity
unlikely to repeat itself for centuries.
Jens Kieffer-Olsen, M.Sc.(Elec.Eng.)
Slagelse, Denmark
====================
(6) SIMULATING ARMAGEDDON ON YOUR PC
From Michael Paine <mpaine@tpgi.com.au>
Dear Benny,
Thanks for posting my latest Explorezone article on CCNet. It
also
appeared at Space.com
http://www.space.com/science/solarsystem/asteroid_software_000110.html
Perhaps the simulation software (written by John Lewis) would
make a
good starting point for the new NEO Task Force in the UK since it
addresses the issues of risk and consequences of impacts.
I have created a web page with extra information from my
simulation at:
http://www1.tpgi.com.au/users/tps-seti/sta1046.htm
It includes a table and graphs showing key statistics, such as
average
fatalities by impactor size and probability of a fatal impact.
regards
Michael Paine
===================
(7) FOSSILS & THE K-T BOUNDARY
From Bob Johnson <bob_johnson@talk21.com>
from CCNet 002/2000 6.1.00:
"When looking at the physical [K-T] boundary in
the geologic record,
a thin, iridium-rich layer of clay separates the
two, according to
research first published in the journal Science by
Luis Alvarez in
1980. The unusually high levels of iridium point to
an
extra-terrestrial source, such as an asteroid, for
the element. What
is more telling, though, is that the cretaceous
layers are often
fossil-rich, while the later tertiary layer is
relatively
fossil-poor, seemingly pointing to a massive
extinction event. By
studying the core samples, scientists expect to see
a blow-by-blow
account of how the biosphere bounced back in the
aeons following the
impact."
Dear Mr Peiser,
the above quote seems to assume that creation of fossils is a
normal
process during the cretaceous period and therefore concludes that
the
lack of fossils in the later tertiary implies that an extinction
event
occurred at the end of the cretaceous.
Suppose however that fossils are only created in catastrophic
conditions, under which the skeletons and soft tissue are buried
with
fresh debris before having a chance to decay. The massive
deposition of
fossils in the cretaceous could therefore be seen as the result
of a
catastrophe; and the subsequent paucity of fossils in the
tertiary could
be either the result of the mass extinction or the consequence of
a
return to calmer conditions in which normal decay processes
pre-empted
fossilisation except in localised situations. One would then need
to
explain the presence of the iridium layer at the boundary i.e.
after the
deposition of the fossils - later fall-out of fine material as
the
atmosphere cleared after the catastrophe, perhaps?
Is there any evidence of fossilisation taking place today on
either a
large or local scale which could support the theory of
"normal" creation
of fossils, or should we be re-assessing the standard
interpretation of
the K-T event?
Yours sincerely,
Bob Johnson
=====================
(8) SUN - A HEAVY IMPACTOR
From Timo Niroma <timo.niroma@tilmari.pp.fi>
Dear Benny,
Space Science News by NASA (science.nasa.gov/newhome/headlines/
ast16dec99_1.htm) is titled "Solar cycle ups and downs
continues to
mystify scientists." I see no reason why they should mystify
anybody.
First the Sun is much more variable than previously
thought. That
should not come as any surprise to scientists. Secondly the solar
ups
and downs in 1999 are easily explained according the theory I
first
formulated in 1989 and put into Internet in 1998.
According to the first prediction including 1999, made by
National
Geographical Data Center (NGDC) in Boulder, Colorado, in August
1997,
was amazingly accurate. The prediction and actual numbers were
(in
smoothed Wolf numbers):
year month pred. act.
1998 Jun 60 62
1998 Jul 63 65
1998 Aug 66 68
1998 Sep 69 70
1998 Oct 72 71
1998 Nov 76 73
1998 Dec 79 78
1999 Jan 82 83
1999 Feb 84 85
1999 Mar 87 84
1999 Apr 89 85
1999 May 92 90
Only the stagnation from February to April 1999 was not seen in
advance. Obviously, because the NGDC does not use one parameter,
that
according to my theory is essential. But later to that.
However, in March 1998 NGDC made a big mistake. From August 1997
to
February 1998 NGDC had said that "May 1996 marks Cycle 22's
minimum and
the onset of Cycle 23". Based on this premise, the
predictions were
excellent. But in March NGDC suddenly changed the time of the
minimum.
With NGDC's own words: "May 1996 marks Cycle 22's
mathematical minimum.
October 1996 marks the consensus Cycle 22 minimum which NGDC is
now
using." And has used since. It had a catastrophic effect on
the
prediction. June 1998 jumped from 60 to 73 (actual 62),
November-December 1998 from 76-79 to 106-111 (actual 76-78) and
May
1999 from 92 to 136 (actual 90). At the same time December 1999
jumped
from 105 to 159 (year 2000 was not yet included).
When the year 2000 prediction first appeared in June 1998, the
maximum
was predicted due to Mars 2000 with a value of nearly 160.
What went wrong? We can easily see that this prediction will not
be
fulfilled. The Sun is is variable, but not that chaotic. The
behavior
of the Sun should be calculated mathematically, not by voting a
consensus.
According to my theory
(personal.inet.fi/tiede/tilmari/sunspots.html)
the smoothed sunspot Wolf value cannot exceed 90 during 20 months
before Jupiter's perihelion, 100 exactly at the perihelion, and
110 10
months after the perihelion. Jupiter's perihelion was in May
1999. The
actual Wolf value was near maximum allowable, 90.
Now, when the influence of the choice of the time of minimum has
continuously diminished and been replaced by the actual rise of
the
cycle 23, NGDC's predictions look again more reliable. The
predicted
value is 111-113 from February 2000 to Mars 2001, the peak being
somewhere between Mars to November 2000. This sounds reasonable.
NGDC has not predicted the time of the next minimum, but my
deviating
prediction for the length of cycle 23 is the maximum length
allowed for
one cycle, which leads to late 2009 or early 2010 instead of the
generally presented time of 2005-2007.
But back to 1998-1999. The raw Wolf value which hovered between
60-90
in autumn 1998, stagnated to 62-69 from January to April 1999.
Why?
According to my theory this is the Jovian effect: when Jupiter
nears
its perihelion and the sunspot cycle is rising, it sets back to
its
prevailing minimum level and stays there until the perihelion is
reached.
Then the May perihelion causes a temporary rise, in this case 106
in
May and 137 in June. After that follows the low period, far lower
than
the predicted 140-160. In this case the quiet period reaches the
maximum time, which causes the maximum in 2000 to be far lower
(some
110) than the general prediction has been.
If we look back the 250 years that we have more or less reliable
figures, what is mystifying in the Sun's behavior in 1998-2000?
If we
look back the 2000 years that has been estimated from undirect
sources,
we have still less to wonder about. The Sun really is variable,
but
still obeys some strict rules.
What is happening in the Sun is a change to a new mode: the
Gleissberg
cycle has reached its minimum (71 years) and now there will be a
reversal to longer and lower cycles. When the 200-year cycle is
also
nearing its turning point (2010-2030), my theory also predicts a
turn
of the global warming to a global chill. The warm winters of
1990's
correlate very well with the highest smoothed sunspot activity
since at
least 1700's, and probable since 1200's. But that's another
story.
Another interesting paper by NASA was titled "The Day the
Solar Wind
Disappeared"
(science.nasa.gov/newhome/headlines/ast13dec99_1.htm). I
quote: "From May 10-12, 1999, the solar wind that blows
constantly from
the Sun virtually disappeared -- the most drastic and
longest-lasting
decrease ever observed." ... "Starting late on May 10
and continuing
through the early hours of May 12, NASA's ACE and Wind spacecraft
each
observed that the density of the solar wind dropped by more than
98%."
... "According to observations from the ACE spacecraft, the
density of
helium in the solar wind dropped to less than 0.1% of its normal
value,
and heavier ions, held back by the Sun's gravity, apparently
could not
escape from the Sun at all."
According to NGDC, the Wolf sunspot number got a jump a few days
earlier: 08 May the number was 151 and 09 May it was 149, when
the
first-May value was 75 and the peak was followed by a decrease,
so that
the value was 85 in May 24. Compare these to the smoothed value
of May,
90.
Finland whose weather is very sensitive to Sun's exceptional
behavior,
experienced a chill that can only be compared to the chill of
1867. The
Helsinki temperature dropped to 2-3 degrees C from 8 May to 11
May
(night temperatures were from minus 3 to minus 4 in May 11 to
14). In
May 22 the temperature had already climbed to 15 degrees.
According to my theory the Jupiter's perihelion very much
regulates the
sunspot cycles. The last Jovian perihelion occurred just during
those
days in May 1999, when the Sun appeared to behave abnormally. But
the
effect does not include only those few days, it affects the whole
cycle. See more on personal.inet.fi/tiede/tilmari/ sunspots.html.
Chapter 5 includes especially weather data.
The point is that the Sun can be much more guilty of past
calamities
and climate changes than we ever have suspected. When Rome was
nearly
collapsing under Severinus during the third century AD, according
to
Schove (Sunspot cycles, New York 1983) there were 7 cycles of 12
years
in row. (12 years is the orbital revolution time of Jupiter
rounded.)
This means that the Gleissberg cycle was at its maximum, when it
today
is at its minimum. The longer the Gleissberg cycle is, the colder
seems
the climate to be and vice versa. Sporer, Maunder and Dalton
minima are
good indications of this. As is the 20th century winters to the
other
direction.
Timo Niroma
-----------------
CCNet-LETTERS is the discussion forum of the Cambridge-Conference
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The fully indexed archive of the CCNet, from February 1997 on,
can be found at http://abob.libs.uga.edu/bobk/cccmenu.html