PLEASE NOTE:
*
Date sent: Mon, 07 Jul 1997 15:26:41 -0400 (EDT)
From: Benny J Peiser <B.J.PEISER@livjm.ac.uk>
Subject: Re: THE SUNDAY TELEGRAPH
To: cambridge-conference@livjm.ac.uk
Priority: NORMAL
from: THE SUNDAY TELEGRAPH, 6 July 1997
A MILLENNIUM BOMB THAT COULD MAKE AN IMPACT
by Robert Matthews
Every millennium has its pet calamity. For 1000 AD, it was the
Second
Coming. For 2000 AD it is the so-called Millennium Bug, a flaw in
computer software which makes the clocks of the world’s
number-crunchers jump back 20 years on the stroke of midnight of
Dec 31
1999, making planes fall out of the sky and credit-card
transactions
bounce.
This week, some particularly forward-looking astronomers gather
at
Fitzwilliam College, Cambridge to discuss a calamity they believe
could
strike at the start of the fourth millennium, a thousand years
hence.
Their prediction is based on an interesting mix of celestial
mechanics,
climatology and history, which together point to the existence of
a huge
disintegrating comet prowling around our solar system, and
occasionally
hurling chunks of stuff our way - with potentially devastating
effects.
The most impressive clue to the existence of this Damoclean
object
comes in the form of a shallow, mile-wide hollow in the remote
Siberian
taiga, near the Tunguska river. On 30 June, 1908 locals living in
the
area reported seeing, hearing - and in some cases, feeling - the
explosion of a colossal fireball that tore across the cloudless
morning
sky. The blast-wave set seismometers scribbling away around the
world,
recording an event equivalent to the detonation of a 15 megaton
hydrogen bomb.
In 1927 Leonid Kulik, a Russian geologist, finally reached the
"epicentre" of the extraordinary event and found -
nothing. The trees
had been flattened for miles around, all pointing outward from
the
hollow in which he stood, but there was no sign of the cause.
Astronomers are now pretty convinced that the Tunguska event was
the
result of a house-sized chunk of comet, breaking up high in the
atmosphere and sending a supersonic blast-wave down to smash into
the
Earth. While Kulik found nothing, a Russian-led team of
scientists has
recently shown that peat taken from the site contains chemicals
and
isotopes consistent with some extra-terrestrial object having
triggered
the destruction.
The next clue emerged in 1947, when British radio astronomers
discovered that the Earth is bombarded by a shower of meteors -
"shooting stars" - each year around June 30: the same
date as the
Tunguska event.
Analysing the orbit the meteors followed around the Sun, the
astronomers found that the debris seemed to be coming from a
comet
called Encke, first discovered in the 19th century and now known
to be
the major source of dust and debris in our part of the Solar
System.
Then in 1975, seismometers left on the moon by the Apollo
missions
detected a huge storm of 1-ton chunks of meteors smashing into
the
lunar surface - the date: June 22 - 26.
You don’t have to be Sherlock Holmes to suspect these events
may be
connected, and for over a decade now a small group of British
astronomers have been uncovering further clues to the identity of
the
celestial "Mr Big" behind the events. Victor Clube of
Oxford University
and his colleagues have found that ancient Chinese astronomical
records
of shooting stars show regular peaks and troughs over the
centuries,
all consistent with the idea that something in space is breaking
up and
leaving a trail of debris behind it, into which our planet
regularly
blunders.
They have also found similar peaks and troughs in the Earth’s
climate,
suggesting that this debris becomes trapped in the atmosphere and
alters
the amount of sunlight reaching the Earth’s surface.
By combining all the evidence together, Clube and his colleagues
believe that they can now identify the common cause behind all
these
bizarre events. The "Mr Big" is a giant comet that came
into our Solar
System and started to break up about 20,000 years ago, dumping
dust,
debris and smaller comets like Encke into the inner Solar System.
With the impact of some of this debris being capable of repeating
the
Tunguska event over, say, central London, the existence of this
disintegrating comet is potentially very bad news. Happily,
however,
Clube and his colleagues calculate that most of the time the
Earth
keeps out of the thickest part of the debris. As a result, all we
usually know of the existence of the debris trail is the annual
meteor
shower and the occasional big hit like Tunguska.
But using the laws of celestial mechanics, it is also possible to
estimate when the Earth will enter the thickest part of the
debris
again. Clube and his colleagues have done their sums, and found a
date
of around 3000 AD - just in time for the next millennial
celebrations.
It’s a pretty impressive prediction - and one that even many
astronomers find hard to take seriously. But there’s no need
to wait to
see if it will come true: enough may already be known for a
search to
begin for the disintegrating comet. Professional astronomers have
usually got something more academic and boring to do with their
telescopes, so perhaps this is a job for the dedicated band of
amateurs
out there.
*
Date sent: Mon, 07 Jul 1997 09:19:13 -0400 (EDT)
From: Benny J Peiser <B.J.PEISER@livjm.ac.uk>
Subject: TREE RINGS, VOLCANOES & THE BISHOP OF ARMAGH
To: cambridge-conference@livjm.ac.uk
Priority: NORMAL
MORE ON THE ~2300 BC ABRUPT CLIMATE CHANGE: TREE RINGS, HEKLA 4
& THE
IRISH ANNALS
from: Prof Mike Baillie <m.baillie@queens-belfast.ac.uk>
Detail from Baillie, M.G.L. (1995) "Dendrochronology and the
Chronology
of the Irish Bronze Age" paper in "Ireland in the
Bronze Age". Ed
Waddell, J. and Shee-Twohig, E, Stationery Office, Dublin, 30-37.
2345 BC.
The earliest of the four (extreme tree-ring events) takes place
at a
time which must be very close to the beginning of the Bronze Age
in
Ireland. This is the so-called Hekla 4 volcanic eruption. It
shows up
as an extremely narrow band of rings, beginning in 2354 BC and
reaching
lowest growth - the narrowest rings - at 2345 BC. It is apparent
that
trees in Lancashire also show reduced growth at the same time,
reinforcing the view that this is a widespread event. While the
event
was very apparent in the ring width patterns, it was a surprise
to
discover a highly unusual growth defect in one of the sample from
the
Motorway complex (trees which grew in the fenlands just to the
south of
Lough Neagh). The sample shows a change in the character of
growth,
from normal ring porous to diffuse porous - an anomaly which
lasts for
about a decade and which could be consistent with the tree being
inundated. So, there is clear evidence for an environmental event
affecting oak growth generally and trees near Lough Neagh
specifically.
However, the evidence in this case is not limited to the oaks
themselves.
Tephrochronology involves the identification and dating of
microscopic
volcanic glass shards and their use as marker horizons in ancient
deposits. Recent work has indicated that Hekla 4 tephra, which
can be
specifically identified to that Icelandic volcano on chemical
grounds,
is found in numerous Irish peat bogs at 2310 +/- 20 CalBC. The
dating
exercise used a series of high-precision radiocarbon measurements
on
stratified peats across the Hekla 4 layer and it is likely that
the
date given above is correct in absolute terms to within a half
century.
So the implication may well be that the narrow growth rings and
associated tree-ring effects after 2354 BC are directly due to
the
environmental effects of Hekla 4. Now that raises interesting
questions. Because the radiocarbon dates associated with this
event
would be almost indistinguishable from radiocarbon dates for the
earliest section of the Beaker period, it becomes possible to ask
if
the Hekla 4 event was in any way related to the arrival of the
first
metal users in Ireland? It is also known that pine pollen
disappears
from pollen spectra in the north of Ireland just a few
centimetres
above this event in most pollen diagrams. Is it possible that
the demise of pine is linked to the arrival of those same
metal-using
people? We may be beginning to see the start of the Bronze Age in
some
sort of wider context, involving a package of
(a) environmental events,
(b) the arrival of at least a new technology and
(c) the disappearance of a species (pine) which
had been present in Ireland for millennia
This sort of package is suggestive that humans were almost
certainly
involved in the demise of pine trees in Ireland. However,
irrespective
of the pine issue, it is clear that some interesting things took
place
in the 24th century BC. The evidence is indelible and is not
going to
go away. I would suggest that this is a classic "marker
date" i.e. a
date which will show up on a regular basis in studies of various
kinds.
It has to be noted that Warner sees the 2354 BC to 2345 BC event
as
very close to one of only four major disasters recorded in the
Anno
Mundi section of the Irish Annals. One of these references bears
the
date AM 2820 (which Warner interprets as "2380 BC") and
says 'Nine
thousand...died in one week. Ireland was thirty years waste'
(i.e. to
2350 "BC"). A coincidence perhaps? In fact, although
Warner draws
attention to the human aspect of catastrophe in the Annals, it
transpires that things are even more curious. The Annals go on to
say
that in "about AM 2859 and after" (i.e. "2341
BC" and after) "lakes
erupted". Of course we know that these ancient annals have
no basis in
fact - or do they? Incredibly, there is an even more bizarre
coincidence.
While we are talking about innundation of oaks at the south of
Lough
Neagh (in Co Armagh) in the period 2354 BC to 2345 BC (dated by
totally
independent dendrochronology), an earlier scholar with Armagh
connections, namely Bishop Ussher, worked out the date of the
biblical
Flood to be 2349 BC (see King James Bible)! There are several
things
which could be said about these coincidences, two of which seem
appropriate. The first is a question; did the scholars who worked
up
the Anno Mundi section of the Irish Annals in fact use the same
Biblical sources as Ussher to derive their chronology? Indeed, is
it
possible that the various scholars came into direct contact
somewhere
in Donegal? If they did, then the prehistoric section of the
Annals
are probably as compromised as critics suggest. The second point
is
merely amusing; maybe all those aged farmers who said the bog
oaks were
"all washed down in The Flood" weren't so completely
wrong after all.
Mike Baillie
Palaeoecology Centre
School of Geosciences, Queen's University, Belfast
(01232) 335147
m.baillie@queens-belfast.ac.uk
*
Date sent: Mon, 07 Jul 1997 08:32:34 -0400 (EDT)
From: Benny J Peiser <B.J.PEISER@livjm.ac.uk>
Subject: Amateur Astronomer Discovers Aten-Class Asteroid
To: cambridge-conference@livjm.ac.uk
Priority: NORMAL
from: Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
http://cfa-www.harvard.edu/cfa/ps/pressreleases/1997MW1.html
PRESS INFORMATION SHEET:
1997 MW1 -- AMATEUR ASTRONOMER DISCOVERS ATEN-CLASS MINOR PLANET
Produced at the Harvard-Smithsonian Center for Astrophysics
(CfA),
Cambridge, Massachusetts, U.S.A.
----------------------------------------------------------------------------
An American amateur astronomer has discovered the latest addition
to
the rare class of near-earth objects known as Atens.
Arizona astronomer Roy Tucker was observing fields in the Milky
Way for
his HELIOS (High Ecliptic Latitude Interplanetary Object Search)
program on June 28 when he detected a fast-moving object. He
followed
it up the next night, then reported accurate measurements from
both
nights to the Minor Planet Center (MPC). With a daily motion of
about
1.1 degrees (for comparison, the diameter of the moon is 0.5
degrees
and main-belt minor planets will have daily motions smaller than
this)
the object was clearly interesting, so it was added to the
Center's NEO
Confirmation Page in the expectation that other observers would
confirm
the object and obtain sufficient observations to allow orbit
computations.
Early attempts by other observers to confirm the object were not
successful, possibly because the object was fainter than expected
on
the basis of Tucker's initial report. Tucker reported his third
night
of observation at 13:45 UT on July 1. The first follow-up
observations
by observers other than the discoverer came from two Japanese
observers
around 16:00 UT that day. The prediction on the Confirmation Page
was
updated, but it was felt that there were not yet enough
observations to
announce the discovery on a Minor Planet Electronic Circular
(MPEC).
Over the next ten hours additional observations came from
observers in
the Czech Republic, Australia, Italy and the U.S. By the morning
of
July 2 the orbit computations was considered secure. The object
was
designated 1997 MW1 and an MPEC announcing the discovery was
issued at
12:29 UT.
Aten-type minor planets have mean distances from the sun less
than 1
astronomical unit (roughly the distance of the earth from the
sun, 150
million km), but move out beyond the orbit of the earth when
farthest
from the sun. Because Atens spend a lot of time close to the sun
as
seen from the earth they are rather difficult to discover. The
discovery of 1997 MW1 brings to 25 the number of known Atens and
this
is the first Aten to be discovered by an amateur astronomer.
The orbit of 1997 MW1 is inclined at about 130 to the plane of
the
earth's orbit. The distance from the sun varies from 91 million
km (at
perihelion) to 189 million km (at aphelion) over the course of a
331-day orbit, but 1997 MW1 does not currently come within 15
million
km of the earth. 1997 MW1 will pass its aphelion point on July 9
and
the object should be observable for a few months, but it will
fade
quite rapidly. Although the diameter of 1997 MW1 is unknown, a
possible
range is 350 to 750 metres, depending on how much light the
surface
reflects (if the surface is dark, the object's size will be near
the
upper limit). 1997 MW1 is the second Aten discovered so far in
1997 and potentially the largest such object since October 1994.
It would appear that Tucker will be eligible to be the first
recipient
of the recently-announced "Benson Prize for the Amateur
Discovery of
Near-Earth Asteroids". It is worth emphasizing that Tucker's
ability to
produce accurate astrometric positions for his discovery was
vital in
allowing the object to be confirmed. Without accurate coordinates
reported immediately, the object could well have become lost.
Roy Tucker was born in Jackson, Mississipi, in 1951, grew up in
Memphis, Tennessee and currently lives in Tucson, Arizona. He
gained a
BS in Physics in 1978 from Memphis State University and a MS in
Scientific Instrumentation in 1981 from the University of
California,
Santa Barbara. He is currently chief electronics engineer for an
optical metrology company in Tucson and sole proprietor of
Southwest
Cryostatics, a company offering construction of homebuilt
charge-coupled device (CCD) detectors. His private observatory,
the Goodricke-Pigott Observatory, houses a 0.36-m
Schmidt-Cassegrain
equipped with a CCD detector. The telescope's field-of-view is
0.2
degrees and the faintest stars detectable (mag. 20.5) are
1/640000 as
bright as the faintest stars detectable by the unaided eye. 1997
MW1 is
the first major result of his HELIOS program, begun in May 1997,
and
was found after a total of 28 hours of imaging and the
examination of
83 pairs of images.
1997 July 2, updated July 3
----------------------------------------------------------------------------
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