CCNet, 53/2000 - 3 May 2000

     "It was one of those Woodstock-style events that punktuate the
     steady flow of scientific progress now and then: The first 
     scientific conference after a rare space event can sometimes turn
     into a fast-paced presentation of one mysterious and/or
     spectacular observation after the other, with often little
     theoretical understanding - but everyone present feels that
     something special has happened and that years of scientific work
     will be initiated by the encounter with the unknown. The sessions
     on the Great Comet Crash of 1994 at the IAU General Assembly in
     The Hague were such a special event - and the Leonid MAC 2000
     Workshop in mid-April in Tel Aviv was no less exciting."
         -- Daniel Fischer

    Michael Paine <>


    Daniel Fischer <>

    Ilan Manulis <>


    P.A. Bland*) &  T.B. Smith, NATURAL HISTORY MUSEUM

    M.S. Kelley*) & M.J. Gaffey, NASA,LYNDON B JOHNSON SPACE CTR

    A. Milani etal., UNIVERSITY OF PISA

    The Boston Globe, 1 May 2000


From Michael Paine <>

Dear Benny,

I was away last week so missed the posting of my article on
the status of Spaceguard. A copy is included below. My holiday also
meant I had no opportunity to comment on the editorial changes. A
couple of the changes deserve clarification.

Firstly, the article was given a somewhat negative slant "An Earth
bound comet could still kill us ... but we may be able to actually see
it coming". In fact a full Spaceguard program should give us decades of
warning about a pending impact - enough time to take evasive action.
Oddly the article did not link to my "Defending Earth" story
which showed that defending the Earth from asteroids was feasible,
provided sufficient warning time was available.
( )

Here are some key points about the status of Spaceguard:

NASA: Speaking as a scientist rather than a NASA official, Don Yeomans
discussed NASA's plans. He stressed the need for a worldwide follow up
effort and better coordination of search efforts. He also explained
that NASA's task includes determining the physical characteristics of

Japan: Dr Syuzo Isobe sent me details about the operation of the new
Bisei Spaceguard Centre in Japan. The 0.5 m telescope is in operation
and the 1m telescope should be ready in September this year. The budget
and staffing details kindly provided by Dr Isobe will enable me to
review my 3 year old proposal for an Australian centre
( - I was not far
off the mark)

NEAT: started observing with a new 1.2m telescope in February.

Spacewatch: Jim Scotti - The 1.8 meter telescope should be ready for
initial use and testing later this year. They have upgrades to the 36
inch telescope in the works as well which will increase its area
coverage by about a factor of 10

LINEAR: Grant Stokes - A second 1m telescope was added to the program
last October. This allowed them to improve their search strategy and
detect fainter objects - "now better than Magnitude 20" (see below).
The LINEAR website has a map of planned sky coverage each month.

SCAP: Dr Jin Zhu from the Bejing Observatory reported that telescope
time devoted to the SCAP NEO search had reduced during 1999.

Australia: Rob McNaught - 0.6m telescope being upgraded for NEO search
work in association with theh Catalina Sky Survey (funded mostly by
NASA - still no Australian government funding).

ODAS: Alain Maury - the project closed down a year ago, initially for
refurbishment but now looks like it won't restart!

Catalina Sky Survey and LONEOS - no news

Equipment needed to meet to goal

In 1998 Alan Harris from NASA looked at the requirements to meet the
Spaceguard (now NASA) goal of discovery 90% of Near Earth ASTEROIDS 1km
or larger within a decade. He found that 6 telescopes that reached 20.5
magnitude could achieve the task - including some automatic follow-up
work (but detailed follow-up work by other telescopes will
still be critical). He noted that, with recent technology advances, 1m
telescopes should be adequate (compared with 2.5m telescope envisaged in
1992) BUT THIS WAS YET TO BE PROVEN (from time to time Al conducts
statistical analysis of the performance of each of the NEO search
programs to calculate their effective limiting magnitude). If 1m
telescopes can do the job then, by the end of the year, there will be
at least 5 this large dedicated to NEO discoveries (LINEARx2,
Spacewatch, NEAT and Bisei). According to Al's calculations ONLY ONE

Given the ups and down of previous programs in Australia and Europe, in
may be wise to have a few more spread around the globe. In particular,
Rob McNaught runs the only professional NEO search in the southern
hemisphere and there are no plans to reach the capabilities of LINEAR.
In theory, given sufficient time, there is no pressing need for a
southern hemisphere site with such capabilities because eventually NEOs
will reappear in northern hemisphere skies. However, there is a remote
chance that an Earth-threatening NEO will be discovered too late (to
take mitigating action) because it was not detected while in southern
skies. In any case, as recent events have shown, good follow-up programs
are needed in the southern hemisphere to support northern hemisphere
discoveries. My opinion is that a semi-automated system like LINEAR
would be the best approach, combined with  the follow-up system that
Rob is working on (in effect the same setup as Bisei).

Finally, the issue that struck me most in researching the article is
the lack of a detailed international plan to achieve the Spaceguard
goal. Up to now it appears that the observatories have been more in
competition that co-operation (fulled partly by NASA's comparison graph
of NEO discoveries). This has been great for accelerating the
development of technology but it seems to me that it is now time to
step back and formulate a plan for effective use of the powerful
systems that will be available by the end of the year. Spare a thought
also for groups such as the Minor Planet Centre that could be swamped
by the increased discovery rates if insufficient resources are

Links and references are at:

Michael Paine

Bigger Telescopes Seek Killer Asteroids
By Michael Paine 26 April 2000

An Earth-bound asteroid or comet could still kill us but thanks to
powerful telescopes slated for addition to the worldwide detection
effort, we may be able to actually see it coming.

In Japan, a telescope at the Bisei Spaceguard Center (BSGC) came online
in February. Its mirror is only 20 inches (a half meter) in diameter,
but scientists plan to upgrade to a larger 40-inch (1-meter) diameter
scope in September. And a couple months ago, the long-running
Near-Earth Asteroid (NEA) Tracking project at NASA's Jet Propulsion
Laboratory upgraded to a larger telescope that also makes monthly
observations three times more often than before.

Also, in terms of sheer mirror width, the Spacewatch asteroid-seeking
team at Kitt Peak in Arizona is about to bring down the house. Later
this year the team hopes to start using a 6-foot (1.8-meter) telescope,
along with a 0.9-meter telescope already in use. The bigger telescope
will help scientists search for fainter objects and cover greater areas
of sky.

Thanks to those changes, scientists soon will be one scope away from a
"magic number" total of six telescopes with mirrors at least 1 meter
across in use for detecting asteroids. In 1992, the "Spaceguard Report"
recommended that six telescopes with mirrors 2.5 meters across be built
to discover within 10 years about 90 percent of large asteroids with
orbits approaching Earth. Bisei will bring the total to five.

Efforts were falling quite short of that goal, while movies such as Deep
Impact and Armageddon publicized the threat of "killer" asteroids and

But two years ago, NASA scientist Alan Harris said the 90 percent in 10
years goal could be achieved with six scopes as small as 1 meter across.
So now a decent shot at forecasting our demise is on the horizon,
though how fast we'll find all those rocks and what we'd do about it
both remain unclear.

Busy at Bisei

Syuzo Isobe of the Japan Spaceguard Association (JSA) described to the $7 million Bisei Center, operated by the JSA and funded
by the Japanese Space and Technology Agency (STA).

"It will have two telescopes and six full-time staff," Isobe said. "The
running cost this fiscal year is about $600,000. The center also would
find space debris that could pose a hazard to Japan's STA's science
satellites currently orbiting Earth."

The Bisei Spaceguard Center's second telescope will have similar
capabilities to the Lincoln Near-Earth Asteroid Research (LINEAR)
asteroid-detecting telescopes in New Mexico.

LINEAR, which also uses two 1-meter telescopes, is by far the most
successful asteroid search program to date. According to NASA, during
1999 LINEAR accounted for more than 70 percent of the discoveries of
large asteroids.

LINEAR now faces tougher competition from Bisei, Spacewatch and NEAT
(Near Earth Asteroid Tracking), which upgraded from a 1-meter telescope
to a 4-foot (1.2-meter) telescope at the Maui Space Surveillance Site
in Hawaii. (NEAT temporarily closed during 1999 and this boosted
LINEAR's proportion of discoveries).

Japan bonus

The entry of Japan into the search for killer rocks helps
geographically, said Don Yeomans, manager of NASA's Near-Earth Asteroid
(NEA) program office.

"The entry of the Japanese search effort is a very welcome one for a
couple of reasons," Yeomans said. "It will add longitude diversity for
the ongoing search efforts so that weather problems in the U.S.
Southwest (where most U.S. search programs are based) will not be such
a problem.

"Also, a discovery of a near-Earth object (NEO) [from] the [continental]
U.S. or in Hawaii could be followed up easily by the Japanese site,
which is several hours to the west," he said. "A very close, fast
moving object can be quickly lost unless followed up immediately."

Follow-up observations are needed to track an asteroid over several days
or weeks. They enable the orbit to be calculated. In 1998 a
"potentially hazard asteroid" called 1998 OX-4 was detected by the
Spacewatch team, but was lost due to the lack of follow-up 

Another benefit of a non-U.S. search team is "political diversity,"
Yeomans added. "NEOs are an international problem and they require an
international solution. The more international partners that are
involved, the less the entire effort need depend upon NASA-supported

Project Spaceguard

In his 1973 novel Rendezvous with Rama, Arthur C. Clarke describes a
fictitious asteroid impact in Europe in 2077. This event forces
Earthlings to create a "Spaceguard" system to detect and deflect
Earth-threatening asteroids and comets. So far, most scientists and
politicians, not to mention the public, have embraced such an approach.

For now, NASA has embraced the recommendations of the Spaceguard Report,
named for Clarke's vision, and is aiming to find most of the large

The report identified asteroids 1 kilometer or larger as the main risk
to civilization. The group acknowledged that comets and small asteroids
also posed a threat but felt that less priority should be given these

Debate continues over the risk from these other objects but there is
general agreement that the large rocks, at least, should be found. For
now, there is no international commitment or cooperation to achieve the
Spaceguard goal.

Recent downward revisions to the estimated number of large near-Earth
asteroids will not make much difference to the required survey effort.
The odds of a collision with the Earth might be reduced but the same
amount of sky still needs to be searched each month -- there will
simply be fewer large asteroids to find because they will be spread
more thinly across the sky.

There is an unexpected benefit with a scheme to detect large asteroids.
Harris's calculations suggest that an ongoing search using six
telescopes will also detect many of the most threatening smaller NEOs
because, before hitting us, they are likely to buzz the Earth during
several orbits of the sun. Being close to the Earth means they are
likely to be picked up by a vigilant Spaceguard program.

International efforts

Spaceguard efforts have had ups and downs in other countries. Jin Zhu
runs the Schmidt CCD Asteroid Program (SCAP) asteroid search project at
Beijing Observatory in China. He told that the time allocated
to asteroid detection at the observatory had reduced considerably
during 1999.

In Australia Rob McNaught reports that he plans to have the 0.6-meter
Uppsala telescope operational early in 2001. McNaught runs the only
professional search program in the southern hemisphere and this is
regarded as particularly important for follow-up observations.

The project is mostly funded under NASA's NEO Observations Program and
is associated with the Catalina Sky Survey in Arizona. Between 1990 and
1996 McNaught was part of the "Spaceguard Australia" team looking for
NEOs from the Anglo-Australian Observatory in Australia. That search
effort found 30 percent of all new NEOs up to 1996, when the Australian
government withdrew funding.

The news from Europe is not good. The OCA-DLR Asteroid Survey (ODAS)
asteroid tracking project, located near Nice in France, stopped
observing in April 1999 so it could be refurbished. Alain Maury, ODAS'
technical project manager, told that, following management
changes the telescope had closed down. "I am currently looking for a
new job," Maury said. "I don't think the Schmidt telescope will reopen
anytime soon."

Still, assuming that the latest systems can be configured to detect
sufficiently faint objects, only one more dedicated telescope with a
diameter of 1 meter or larger would be required to achieve the
Spaceguard goal within a decade.

However, given the uncertainties with near-Earth asteroid search
programs in recent years, perhaps it would be wise to have a few more
telescopes spread around the world. Arthur C. Clarke may prefer to be
known as a visionary rather than a prophet of doom.

Major Programs Searching for Near Earth Asteroids and Comets

Name and location                    Equipment         Status

Bisei Spaceguard Center (BSGC)       1-meter           0.5-meter
                                     telescope &       telescope          0.5-meter         commissioned in
neo/index.html                       telescope, both   February 2000.
Okayama, Japan                       used for          1-meter should 
                                     detecting NEOs    ready September
                                     and space         2000.

Catalina Sky Survey (CSS)            0.7-meter         Pays greater
                                     telescope,        attention to      dedicated to      objects high in
                                     NEO work          the northern sky
Mt Bigelow, Arizona                                    than other
                                     Magnitude 19.2    surveys.
                                                       Plans to pgrade
                                                       a 1.5-meter
                                                       telescope at Mt.

Lincoln Near-Earth Asteroid          1-meter           Responsible for
Research (LINEAR)                    telescope         percent of large
                                     originally        near-Earth         developed for     asteroid
                                     tracking          discoveries in
White Sands, New Mexico              satellites. Two   1999.
                                     are now mainly
                                     doing NEO work.   Second telescope
                                                       began in October
                                     Magnitude 19      1999..
                                     (maybe 20.5)
Lowell Observatory Near Earth        0.6-meter         Concentrating on
Object Search (LONEOS)               telescope         detecting large
                                      dedicated to      NEOs.         NEO work
                                     Magnitude 18.5.
Flagstaff, Arizona
Near Earth Asteroid Tracking         1.2-meter         Recently
                                     telescope         from a 1-meter
                                     dedicated to      GEODSS
       telescope,            NEO work.         magnitude 19.

Maui, Hawaii

OCA-DLR Asteroid Survey (ODAS)       0.9-meter         Closed down in
                                     telescope         April 1999.

Nice, France

Schmidt CCD Asteroid Program         0.6-meter         Telescope time
(SCAP)                               telescope. NEO    reduced during
                                      work is           1999 due to
other          secondary.        demands for the
~zj/scap/scap.html                                     telescope.

Beijing Astronomical Observatory,

Southern Hemisphere Survey           0.6-meter         Plans for
                                     Uppsala           commissioning          telescope will    early in 2001.
css/csssouth.html                    be dedicated to
                                      NEO work          The only
Siding Spring, Australia                               professional
                                                       search in the

Spacewatch                           0.9-meter         A 1.8-meter
                                     telescope         telescope is
                                                       under          dedicated to      construction
spacewatch/                          NEO work

Kitt Peak, Arizona                   Magnitude 21.5


Magnitude is essentially a measure of the faintness of an object.
The higher the magnitude, the fainter the object. Magnitude 21,
which is a typical upper limit for the above surveys, is exceedingly
faint. Background light such as the Milky Way or moonlight will
swamp any objects of this magnitude. A typical 1-kilometer asteroid
would have a magnitude of 18 when observed about 100 million miles
(160.9 million kilometers) from Earth, in the opposite direction
to the sun. Spaceguard scientists need to detect these objects at
larger distances and at less favorable angles, where they will appear
fainter. Magnitude 20.5 has been suggested as an appropriate limit
for reaching the Spaceguard goal of detecting 90 percent of these
large asteroids within a decade..

All the above systems use CCD detectors for recording the images.
These are similar to the devices used in camcorders to collect light
digitally. To eliminate the effects of random bright spots in the
images (mostly caused by cosmic rays) the usual procedure is to
take between three and five shots of the same portion of sky.
Sophisticated computer programs have been developed to scan the
resulting images for signs of NEOs.

Next: Space-Based Telescopes for Asteroids?

Several scientists have pointed out limitations to the observation of 
asteroids and comets using only Earth-based telescopes, but Japanese
and European scientists are offering a solution.

Without the atmosphere's glare, a telescope based on the moon or
elsewhere in space could search the region between Earth and the Sun,
says the Japan Spaceguard Association. Infrared detectors on
space-based telescopes would be better at determining the physical
properties of asteroids and comets than ground-based equipment.

A consortium of European scientists also has proposed a space-based
telescope called Spaceguard 1. The project recently missed out on being
selected by the European Space Agency (ESA) for a low-budget

"It is encouraging that the ESA Working Group that selected the missions
recognized the wide intrinsic interest of our mission [the risk to the
planet]," said Alberto Cellino, a consortium member. "We will continue
to explore all the possibilities to develop this space-based

Don Yeomans of NASA's NEO (Near-Earth Object) office said he is unaware
of any U.S. plans to launch a space telescope to look for asteroids and
comets. But he said space-based telescopes already up could contribute.

"Space-based surveys in the optical and infrared will observe countless
asteroids," he said, "whether they wish to or not. And perhaps this is
the most cost-effective method for space-based near-Earth asteroid
research -- to ride on the coattails of programs designed for observing
objects other than NEOs."

Copyright 2000


From, 2 May 2000

Experts Demand Better Asteroid Alert
By Leonard David
02 May 2000

WASHINGTON -- Talk about a wake-up call.

On February 1, 1994, high over the Western Pacific, a huge fireball
from space exploded with the equivalent energy of a 40-kiloton bomb --
twice the power of the atom bomb dropped on Hiroshima near the end of
World War II.

So large was the blast that U.S. military satellites and military brass
believed a nuclear device had detonated.

Up the chain of command went the worrisome code word "NUDENT" --
military jargon for nuclear detonation. Word in intelligence circles
was that President Clinton was awoken that night by senior advisors.
Only later did analysis confirm that the high-altitude explosion had
come from a non-nuclear source.

It turned out the Earth had been on the receiving end of a huge space
rock -- a troublesome, extraterrestrial invader from afar.

The event was a smaller version of the 1908 meteorite explosion above
Tunguska, Siberia, that unleashed an explosion force equal to 15
megatons of TNT. That blast flattened some 2,000 square kilometers of
forests. Similar wake-up calls have peppered the Earth throughout the
ages -- and our planet has the scars to prove it.

Rock of the ages

Between 30 to 50 times a year, scientists say, a fireball comes
screaming through the Earth's atmosphere. Chances are you never hear
about most of these intruders.

Since the late 1970s, military satellites have spotted about 400 such
events. So far most of the data has remained classified. Scientists
estimate that nine out of ten fireballs remain out of public and
scientific view.

Of course, there is the supposed mega-blast that wiped out the
dinosaurs 65 million years ago. But one of that magnitude is an
exceeding rare event, one that is not real to most people.

"Conversely, I can show people evidence of real strikes inflicting
local and regional damage less than a century ago," said Brigadier Gen.
Pete Worden, deputy director for command and control headquarters for
the Air Force. "Even more compelling are the frequent kiloton-level
detonations our early warning satellites see in the Earth's atmosphere.
These are threats the public and its leaders will take seriously," he

Worden emphasized he was speaking solely for himself. The Defense
Department has no official view on threats from space rocks.

The watch for space rocks

But getting the word out on these heavenly visitors appears to be a
cumbersome process.

"There doesn't seem to be a systematic and recognized approach for
dealing with this kind of data," said Richard Spalding, an engineer at
Sandia National Laboratories at Kirtland Air Force Base in Albuquerque,
New Mexico.

"We have a capability in the satellites of seeing very bright,

transient events in the atmosphere. Anything that's big enough for us
to see is something worth paying attention to," he told

Spalding is one of a growing cadre of experts familiar with hush-hush
satellite data who argue that such information should be released
faster and shared throughout the scientific community. One idea is to
build a "response capability" using Air Force Defense Support
Program (DSP) satellites.

These globe-circling spacecraft could issue a "near-real-time" message
of an airburst, spelling out the location and at what altitude the
explosion may have occurred, said Richard Davies, President and
Chairman of the Western Disaster Center, Moffett Federal Air Field,
California. The center is a non-profit research group focused on
high-tech ways to improve disaster and emergency management.

"There is [a] need to use existing capabilities to increase the level
of monitoring," Davies said. "The capability is there to do this in
real-time, not report on an event months later. Sometimes it has taken
that long.

"We could have a small Tunkuska-like event over a populated area with
people hurt and killed," he said. "It might take hours or even days
before there is any communication from them."

Davies said that such sky-watching duties using current and future
military spacecraft could be folded into the newly-created Global
Disaster Information Network (GDIN). Established by President Clinton
on April 27, the GDIN is a multi-federal agency group whose duty is to
use information technology to reduce loss of life and property from
natural and human-made disasters.

The issue is stirring attention overseas as well.

Joining the call for more action on threatening space rocks is
Spaceguard UK, an international group of scientists and researchers
based in Salisbury, England.

A British government task force is investigating the threat posed to
Earth by incoming space objects. It is to make its recommendations to
Britain's Minister of Science next month.

The process of releasing information about space rocks "certainly could
be improved," said Edward Tagliaferri, a consultant to the Aerospace
Corporation in El Segundo, California. He analyzes infrared data
gleaned from Defense Department satellites and, if given a go-ahead,
releases that data to the scientific community. He would not say which
government agency dictates the release of such data.

"Right now, it's done on a case-by-case basis," Tagliaferri said. It's
not like they aren't aware of the value of this data. It's just that
the workload is significant on their part," he said.

Things that go boom in the night

One event earlier this year points to the need for quick, accurate data
regarding incoming meteorites.

On January 18, over a remote area of northwest Canada, a meteorite
exploded, releasing the equivalent blast of a 4-5 kiloton bomb.

"It was a big object. I estimate somewhere between six and nine-feet
(2-3-meters) in diameter. We don't usually get hit that hard except
once every 5 to 10 years," Tagliaferri said.

Defense Department satellite sensors caught the incoming object as it
plunged toward Earth, he said.

Plowing through the atmosphere above Yukon Territory, sonic booms
startled residents as far away as British Columbia and Alaska.

When the fireball exploded at an altitude of 16 miles (25-kilometers),
it turned darkness on the ground to daylight. So bright was the
explosion that streetlights operating on solar cells turned themselves
off. As the meteorite extinguished itself, the lights immediately
turned back on, overloading the local power grid. That in turn caused
electrical switching hardware to fail.

Being left in the dark by a natural event is one thing. But to
unsuspecting townspeople, might they not consider it a terrorist

"Absolutely. These type of events really do mimic nuclear detonations.
There are definite advantages to the timeliness of releasing this kind
of information," Tagliaferri said.

Also, there are political powder kegs around the globe. A fireball
event could cause a literal spark that lights a fuse.

"When you go down the list of Pakistan and India, China and Russia,
North Korea and South Korea - there are enough people who are at odds
with each other. One of them could be tempted to retaliate to an event
they thought was initiated by somebody else. We need some mechanism
where government to government can communicate in a credible manner
about a natural event," he said. "One of these things is going to hit
somewhere and really cause some serious flap or damage, or both. It's
just a matter of time," Tagliaferri said.

Copyright 2000,


From Daniel Fischer <>

Dear Benny,

here is a report of what I considered the highlights of the Leonids
workshop in Tel Aviv last week - a web version with a few links is at (story 2).



Bewildering torrent of data collected during 1999 Leonid storm

Unique records of rare celestial event on parade at first major
conference / Value of amateur observations hailed / USAF drops out of
Leonid business

It was one of those Woodstock-style events that punktuate the steady
flow of scientific progress now and then: The first scientific
conference after a rare space event can sometimes turn into a
fast-paced presentation of one mysterious and/or spectacular
observation after the other, with often little theoretical
understanding - but everyone present feels that something special has
happened and that years of scientific work will be initiated by the
encounter with the unknown. The sessions on the Great Comet Crash of
1994 at the IAU General Assembly in The Hague were such a special event
- and the Leonid MAC 2000 Workshop in mid-April in Tel Aviv was no less

"MAC" stands for the Multi Instrument Aircraft Campaign that the U.S.
Air Force, NASA and other agencies had run during the 1999 Leonid
storm, and the meeting at Tel Aviv University was the first occasion
for a joint presentation of the observations made from the two aircraft
that had flown "through" the storm near Italy. But many groundbased
teams, associated with MAC'99 or independent, were represented, too, as
were amateur astronomers from Israel (who had observed the storm in the
Negev desert) and Germany (who had been in Tenerife and Jordan).

The theme running through most of the conference could be described as:
"The meteors are coming - let's try something new!" A number of
speakers had used instruments during the meteor storm that had rarely
or never been used for meteor work before: big radar dishes, networks
of radio antennae, HDTV cameras etc. Almost every other speaker had a
video cassette to show with sometimes strange but more often
breathtaking views of the celestial spectacle. The "best picture" award
would clearly go to the wide-angle HDTV tape shot by Japanese
researchers from one of the airplanes which really showed the rain of
several meteors per second during the peak of the storm (H. Yano).
Almost as captivating was a Czech video of meteor spectra in realtime
(J. Borovicka), also shot from the air.

Here are a few of the highlights of the meeting and some early
discoveries - a collection of refereed papers should be published as a
special issue of Earth, Moon, and Planets as well as a book this

You see 7 times as many meteors from the air than from the ground! This
surprising 'discovery' by the airborne observers has been analyzed
theoretically and found to be perfectly logical (D. Koschny): From,
say, 10 km altitude you can look through a much larger volume of the
atmosphere with less extinction than from the ground, so the number of
meteors near the horizon rises dramatically. This fact was also
exploited by the above-mentioned Japanese HDTV system.

How real is the fine structure in the ZHR profile of the peak? There
was considerable debate about the reality of several peaks of the
meteor rate before and after the main peak, with P. Jenniskens arguing
for a remarkably smooth ZHR profile (with a Lorentzian shape) as
generated from multiple airborne video cameras, but several others
(among them I. Manulis, H. Yano, S. Molau and the author) saw clear
evidence for at least one peak 20 minutes before the maximum that shows
up in the airborne video as well as in the Israeli and Jordanian visual
and video data (see also the report about the Radebeul conference in
Update # 182 story 3).

Are there two layers in the atmosphere where the meteoroids burn up?
Puzzling Israeli radar data (N. Brosch) could indicate that one class
of dust particles decays at 250 km and the other at 120 km altitude,
but the result remained controversial and the technical details of the
(military) radar system unknown. The Leonid activity had also been
monitored by a worldwide network of identical mobile radar antennae (W.
Hocking), but many of the detailled recordings have still to be made
public (and could prove the fine structure mentioned above).

What can we learn from the radio emission of meteors? An array of radio
antennae normally used for lightning research had been placed in the
Israeli desert - and recorded up to 18 000 VLF radio signatures an hour
during the Leonid storm that are characteristic for meteors (C. Price).
The tons of data collected have hardly been looked at, but the
tentative activity profile from the meteor emissions is puzzling: There
are both the main and the above-mentioned pre-peak 1/2 hour earlier -
but also a huge number of signatures 1 1/2 hours before the peak that
have no visual counterparts whatsoever...

Nebulous meteors are real! A few researchers had obtained video
recordings of meteors with high  angular resolution - and sometimes
meteors would show an extended V-shaped halo (I. Murray, M. Taylor).
The detailled hydrodynamics of how meteoroids decay in the upper
atmosphere, one could learn at the conference, are not that well
understood, as are the subtleties of the emission spectra from the
meteors. Those, in turn, might eventually even teach us about how
cosmic dust could bring organic molecules to Earth - a reason why even
"astrobiologists" show some interest in the Leonid data.

Will there be more observing campaigns like MAC'98 and '99? The USAF
has concluded that the Leonids are no significant threat to satellites
and that further large enpenditures on observing campaigns would not be
justified from the 'threat' perspective (M. Treu). It had also become
obvious to the military brass that amateur astronomers are very well
capable of monitoring the meteor activity in the sky. The MAC
scientists, though, are most interested in further air campaigns, in
2001 and 2002 (the Moon is less of a problem when you're airborne than
on the ground), and perhaps even in 2000.

This year's Leonid activity will be a decisive test whether there will
really be more storms in 2001 and 2002 and should thus be monitored
well, many speakers emphasized. The leading theoretician of the Leonid
dust trails, D. Asher, stated once more that all reasonable cometary
dust ejection models make Leonid storms in 2001 and 2002 all but
inevitable, and P. Jenniskens is already qualifying his doubts
(mentioned in the just-released June issue of Sky & Telescope) and is
now hoping for ZHRs of 6000 and more in those two years. Again, new and
ususal observing methods are likely to be brought into action, followed
by years of data analysis...

Daniel Fischer


From Ilan Manulis < >

Dear Benny,

You might find the following account of P/2000 G1 LINEAR peculiar orbit
worth mentioning on the CCNet. It seems this newly discovered comet is
an NEO. No meteor shower has been associated with it albeit the fact
its orbit intersected the Earth's few times in the past hundreds of

Best regards,

Ilan Manulis

Head of the Small Solar System Objects Section
The Israeli Astronomical Association

Date: Mon, 24 Apr 2000 01:25:36 -0400
From: Kim Youmans < >
Subject: [IMO-News] P/2000 G1 LINEAR and March meteors
To: Meteorobs < >,

The following is forwarded by permission from John Greaves, and
contains quite a bit of individual research pertaining to comet P/2000
G1 LINEAR and the possibilty of increased meteor rates back in March of
this year, as well as in the future. Please note his identification of
a possible radiant.

P/2000 G1 LINEAR

Hi Kim

Just before the hols kicked in on Friday CBAT/MPC released elliptical
elements for P/2000 G1 LINEAR on their webpages [which I'll just call
G1 from now on!]. They're only based on a ten day orbital arc so far,
all obs being pretty near to perihelion, but I usually interpret the
number of decimals they quote to as an indication of their confidence
in any particular orbit, I they quote a few for it.

I'll split the following up into 3 bits and try and be as terse as
possible.  It's all a tad complex mind'st, so I may well get it
muddled in places. The biggest verdammt problem is having to re-boot
twixt dos, windoze and linux every two minutes in order to run the
appropriate bits of software using the results from other bits!

Improved elements at a later date may affect the fine details, but
some [v.small] experience in these things suggests only the details
and not necessarily the conclusions will change.


G1 was at a 1.003 AU perihelion late 9th March 2000, whilst 0.1 AU
from Earth, though the two had been that smidgette closer on 4th
March. The Earth's orbit was nearest the perihelion point about 17th
March, or at least soon after.  Ascending node was crossed just prior
to midnight 10th April [UT].

When this comet was first discovered a couple of weeks ago I wrote to
you asking about this apparent increase in sporadics that North
American observers had been noticing around March. Well the above
orbit doesn't intersect Earth's, but just the same I did a 'q -
adjustment' gimmick of using an orbit of presumed co-orbital
meteoroids of 1 AU perihelion distance and calculated a radiant.

NOW, I've never had much luck finding out the exact details of how to
calculate radiants from orbits, but a fellah far, far cleverer than I
at such things was kind enough to provide me with a bit of code to do
so a while back [no name - no blame!].  He did note that is wasn't
necessarily fool-proof, but it has tested out okay on some well known

Anyway, this gave a predicted radiant for this orbit adjusted to 1 AU
q [a, the semimajor axis, is barely changed by this adjustment of q],
of 85 Deg RA, -17 Deg Dec, Vgeo 15 km/s [about 10mps]: that is quite
near Arneb (alpha Leporis).

For 80 degs West and 40 degs North geographic coordinates that'd be a
33 degrees altitude at an 18:30 EST transit time for this radiant
position in mid March [23:30 EST setting time], with slow meteors.
Whether this fits the details of any heightened 'sporadic' rate, I
dunno, as I have no data.

However, I do note that there's a possible selection effect with
these 'sporadics': I get the impression that you had a good run of
early Spring weather over there this year, which may not always be
the case, and this in combination with a favourable moon mid March
may not at all be a frequent state of affairs!  Radio scatter details
may tell the truth, but I dunno if they suffer from selection effects
due to solar maximum, and if so, in which direction!!!!!

This comet is a very small object, exemplified by the fact that it
was only magnitude 15 when at a its 0.1 AU closest to Earth.  Whether
such an object can have enough coma/halo to extend all the way to
Earth I dunno! It is fading quickly, and may be lost afore many
observations are made.


When I wrote before I noted that it was not possible to tally G1's
orbit with _any_ catalogued meteor orbits that I could get the bumf
for.  I tested the new elements against the entirety of the IAU photo
and radar databases using Drummond's D' and found _no matches_
whatsoever.  This is really weird, cos invariably one or two meteors
_appear_ to match up to most short period comet orbits, just cos of
general similarities between them all due to past Jupiter

And there's the clue!  G1 crosses the ascending node near its
perihelion.  It also crosses the descending node near to aphelion.
Perihelion is at 1 AU and aphelion at around 5.15 AU.  This may ring
a bell to you re two planets' orbits!  Namely, Earth and Jupiter!

Consequently I did some orbit evolution stuff, including planetary

And straight away I find that this is a new orbit that is only two
and a half revolutions old: ie this is only the new orbit's second
perihelion! In 1987 a roughly 0.2 AU passage at Jupiter changed the
orbit from a previous, slightly different one.

And there were some slight changes from a previous orbit when it came
within 0.07 AU of Earth in early '73, oh and did I mention 0.3 AU
passages at Jupiter in 1939 and 1927, and a 0.06 AU Earth one in
1952, and the 1915 Jupiter one, and the 1880 Jupiter, etc, &c, etc,
and even Venus & Mars getting in on the act twixt 1000 and 1500...
...this comet seems to have had more orbits than some people have
seen Lyrids! It seems to have been in and out of resonances a lot

To cut an even longer story long, some of these orbits did intersect
Earth's, and I calculated a few to see how they went [well, the
software did!].  Maximum dates stretched from late Jan to early Apr,
which at first 'smelled' very nice re Virginids complex!  However,
radiant positions weren't appropriate, with some in Auriga and some
in Taurus.

Further, D' criterion tests against the meteor orbits' databases came
up with little, though there were some hits for a 1985 representative

Basically, this comet (as mentioned) is a very small affair as comets
go, and rarely stays in one orbit long enough to leave a coherent
accumulative debris stream anyway!  So, maybes no meteors...

Take the orbit back far enough and you eventually get perihelion out
by nearish Jupiter and G1 becones an outer solar system object.  I've
tried matching some of these orbits against the current list of known
comets for possible matches [to see if miniscule G1 is a 'chip off
the old block' of any of them] with no success, but I didn't expect
any success here anyway!  We're talking hundreds of years ago here.
Then again I haven't checked all the orbits, there's just so many!


After getting stuck in the present and the past I finally twigged to
look at the future!!!!

Things are moderately promising in that respect, as the orbit is
slowly decreasing in perihelion, ever so slightly, so that it will
soon intersect Earth's!  Jupiter and _possibly_ ourselves are still
affecting the orbit.

Okay, this is how it seems to pan out:-

Perihelion will dip just below 1.0 AU in Feb 2003.  As the elements
are then barely any different, and essentially the same as I used in
an earlier 'q-adjustment' run for 2000, it is no great surprise to
find orbital intersection with a radiant of RA 85 degrees, Dec -17
degrees, March 17th maximum, Vgeo 15 km/s.

This more or less carries on for awhile, with elements barely
changing.  Next perihelion will be at 0.9985 AU in September 2005,
and by then we have RA at 82 degrees, Dec unchanged, Vgeo 16 km/s,
and a maximum date of 22 March, with of course the following year of
2006 therefore being favoured.

Similar things go on for awhile with perihelia in late 2010 and 2021
being followed by March radiants in 2011 and 2022.  The 2016
perihelion is in early May, after March, but nearer than March 2017.

The 2027 perihelion is on 10th Feb, but after that the perihelion
distance again transcends 1 AU.

In 2046 a moderately close approach to Jupiter pumps up the
inclination and raises perihelion distance slightly.

Perihelion tries to crawl back to 1 AU from time to time, but as the
orbit stands at the moment we have a date of 29th August 2117 when the
comet gets within 0.011 AU of Jupiter and consequently an _aphelion_
near Jupiter's orbit thenceforth becomes a _perihelion_ near
Jupiter's orbit!

All the above is bound to change in detail, but from experience I
reckon it will work out being right in general, even with an improved
orbit and higher time sampling resolution.

If this comet does manage to leave a shower trail over the next few
decades, it'd help explain why so many showers have next to no parent
body associated with them!!!!!!


Okay, this comet is a very minor affair, so although having
apparently intersected the Earth's orbit in the past, doesn't seem to
have any showers that can be associated with it.  Soon it'll spend a
quarter of a century intersecting the orbit and possibly providing a
shower... ...possibly not.  Soon thereafter it'll go back to the
outer solar system where it came from after a 'short' two and a half
millenium visit.


When the orbit is next updated, hopefully with a prediscovery image
from around last perihelion in 1994 ish, I'll re-do the future
orbital evolution.  I've used 30 day sampling on this one as the
processing can take quite long!  Now that I know there's only a short
future period to look at, I'll user a far tighter sampling rate.

It's also the holidays at the mo', otherwise I could have checked the
radiant predictions more closely!  A professional solar system bod in
the US has kindly calculated a predicted radiant or two for me in the
past, and he's a bit of a leader in this field, so this Arneb radiant
could be checked.

If we do get any form of shower, let's hope nobody calls it the
LINEARids!  That project has found over 40 comets up to press, though
with no new associated showers as of yet [despite a near thing last
year].  Should a new shower ever appear cos of LINEAR, the first
LINEARID shower would be very interesting, the second LINEARID shower
a confusion, and any third a bloody naming convention nightmare!  I
like Leporids, or alpha Leporids in case someone is scared of lots of
showers cropping up in Lepus.

Mindst, we've got to have a meteor shower first....


John Greaves


A.A. Christou: A numerical survey of transient co-orbitals of the
terrestrial planets. ICARUS, 2000, Vol.144, No.1, pp.1-20


We have investigated numerically the evolution of near-Earth asteroids
(3753) Cruithne, (3362) Khufu, 1989 VA, (10563) 1993 WD, and 1994 TF2
that enter the coorbital regions of the Earth or Venus. We show that
the coorbital libration modes identified in F. Namouni (1999, Icarus
137, 293-314) and F. Namouni et al. (1999, Phys. Rev. Lett. 83,
2506-2509) are strong enough to survive tens of thousands of years
under planetary perturbations in the Solar System. We give a detailed
analysis of the nature of libration modes as functions of the argument
of perihelion. The effects of close approaches with the coorbiting
planet as well as neighboring planets are characterized. Based on these
results, we argue for a steady-state flux of objects temporarily
captured in coorbital configurations with the planets. (C) 2000
Academic Press.


P.A. Bland*) &  T.B. Smith: Meteorite accumulations on Mars. ICARUS,
2000, Vol.144, No.1, pp.21-26


We have modeled single-body meteoroid atmospheric entry speeds at Mars
and the effect of drag and ablation, and identify a narrow range of
small masses (10-50 g) that should impact Mars at survivable speeds.
The rate of oxidative weathering is much lower than that on Earth, so
this small flux of meteorites could give rise to significant
accumulations: ca. 5 x 10(2) to 5 x 10(5) meteorites greater than 10 g
in mass per square kilometer. Given that extremely large numbers of
meteorites may be present on Mars, future sample-return missions should
consider the real possibility that they may recover meteoritic
material. Due to the low weathering rate, meteorites may survive on the
surface of Mars for more than 10(9) years, preserving a record of the
temporal variability of the meteoroid flux and the compositional
evolution of the meteoroid complex. Intact carbonaceous chondrites may
also preserve organic compounds from degradation by ultraviolet
radiation. Terrestrial meteorites may be present, but would probably be
sterile. (C) 2000 Academic Press.


M.S. Kelley*) & M.J. Gaffey: 9 Metis and 113 Amalthea: A genetic
asteroid pair. ICARUS, 2000, Vol.144, No.1, pp.27-38


Recent analyses of spectrophotometric data of asteroids 9 Metis and 113
Amalthea have revealed a probable genetic (compositional) link between
these two objects. The nearly identical composition of the silicate
components of these two asteroids is consistent with their derivation
from a single parent body. Based on the present compositional and
morphological interpretations of 9 Metis and 113 Amalthea, and
using plausible (chondritic) starting compositions for the parent body,
the original parent asteroid is estimated to have been between
approximately 300 and 600 km in diameter. Thus Metis and Amalthea are
the largest survivors of a highly evolved, genetic asteroid family from
which 86-96% of the original mass has been lost. (C) 2000 Academic


A. Milani*), A. LaSpina, M.E. Sansaturio, S.R. Chesley: The asteroid
identification problem III. Proposing identifications. ICARUS, 2000,
Vol.144, No.1, pp.39-53


A large fraction of asteroids have been lost shortly after discovery,
thus the asteroid catalogs contain a large number of low accuracy
orbits. Two of these inaccurate orbits can belong to the same physical
object; the challenge is to find effective algorithms for
identification. We give a new method to propose identifications of
orbits, applicable in the case where each of the two observed arcs
provides enough information to solve for all the orbital elements by a
least-squares fit to the observations. Even if the optimum fit solution
is unique, there is a confidence region in the space of orbital
elements containing orbital solutions compatible with the observations:
the identification of orbits is the search for an orbital solution in
the intersection of the two confidence regions. In the linear
approximation there is a rigorous and simple algorithm to find the
optimum joint solution and the increase in the RMS of the residuals
relative to the two separate solutions. The linear approximation may
fail if two poorly determined orbits are too far apart in the orbital
elements' space. In this case, the linear algorithm becomes more stable
when restricted to only some of the orbital elements. Our procedure
proposes orbit identification using a cascade of tests, all based upon
identification metrics taking into account the difference in the orbits
weighted with the uncertainty, The first test is based only upon the
orbital plane; the couples of orbits compatible according to the first
test are submitted to further tests using identification metrics based
upon 5 and 6 orbital elements. Finally, the couples passing all tests
are submitted to an accurate computation, by differential correction,
of the orbit fitting both sets of observations. This procedure has been
tested on a set of 100 already known identifications and was found to
be effective in 99% of the cases. Finally we show that these methods
have been used to obtain 152 previously unknown orbit identifications.
(C) 2000 Academic Press.


From The Boston Globe, 1 May 2000

New round of star wars: Entrepreneurs battle over celestial naming

By Beth Daley, Globe Staff, 5/1/2000

Trillions of miles away in the Cancer constellation, Krystal Fransen's
namesake radiates.

The North Reading woman has always been the center of her boyfriend's
universe, but he paid the Name a Star company $50 last month to change
the name of star number 098139 to "Krystal," guaranteeing her a more
public place in perpetuity.

But Fransen's and thousands of others' place in celestial immortality
is being threatened by one of the nastiest star wars to hit this corner
of the universe in a long time.

The International Astronomical Union says that only its organizationis
allowed to name anything in the sky, and that the star-naming business
is a scam that real astronomers refuse to recognize. Nonetheless, more
and more buy-a-star companies are popping up on the Web, raising
suspicions that certain star names are being sold twice. Meanwhile, the
star namers have turned on themselves, as the biggest firm sues Name a
Star for allegedly stealing their trademarked name to market Milky Way
real estate.

"I'd like to be sitting in the courtroom for that case,'' said Dennis
di Cicco, associate editor for Sky & Telescope magazine in Cambridge.
"It's sort of amusing because it's a fight over who has the right to
dupe the public. There are very few people who stand neutral on this."

Americans have been naming things after themselves at least since
Christopher Columbus visited in 1492, but the battle over star-naming
rights is a singularly modern form of colonialism. These days,
Americans buy the right to name everything from stadiums to insects in
the tropical rainforest, and they can even petition the US government
to name any landscape feature - even a mound of earth - in the

The obsession with naming things began extending heavenward in the late
1970s, as novelty entrepreneurs capitalizing on the `pet rock' craze
discovered a seemingly infinite supply of free merchandise in the cosmos.
Now, more than 1 million star names have been "sold" and the rest are 
going fast. Hundreds, if not thousands, are being sold every month. But
even if sales sped up, there are billions of stars in the universe.

"It's the supreme form of ego," said Joe Boskin, professor of social
history at Boston University. "And in America, it's crucial.
Immigrants came here and reinvented themselves. Their names conveyed
power and identity in a new place. We are a wealthy nation, and in the
history of mankind the wealthy people want to leave a legacy. That
means their name. Anywhere they can."

For the average folk, the legacy doesn't have to cost the millions 
often required to attach a family name to a college dorm or hospital
wing. It usually costs around $50 to name a star that is virtually
guaranteed to last a good 5 billion years more than its namesake.

All star-naming companies allow customers to choose a star in the
constellation of their choice, selecting the often faint pinpricks of
light using Hubble telescope technology or astronomical catalogs. The
International Star Registry even places star names in a book and locks
it in a Swiss bank.

Virtually none of the named stars are visible to the naked eye, but the
companies promise that almost all can be seen with binoculars or
telescopes. And the purchase comes with a map that identifies the named
star's position in the heavens.

As a result of the star-naming boomlet, the once august business of
naming celestial bodies after the gods of mythology or giving them
precise catalog numbers has been replaced by a new aesthetic:

The Elvis star shines down from the Cepheus constellation and more than
10 Princess Dianas now dot the sky from Orion to Andromeda. Stars named
for Billy Ray Cyrus, Dolly Parton, Sammy Davis Jr., members of the Space
Shuttle Challenger crew, and the ''Star Trek'' crew twinkle in the
night sky. Actor Billy Baldwin even named a star after John F. Kennedy
Jr. when he died, according to the International Star Registry.

But members of the International Astronomical Union say no astronomer
is going to acknowledge these names when charting or analyzing star

The union, made up of professional astronomers around the world, is
responsible for naming celestial bodies and the rules are strict:
Virtually no stars are given names anymore; there are simply too many.
When new stars are discovered, they are given numbers that note only
their celestial coordinates.

Features on planets and their moons are named, but often have to follow
a theme, according to the astronomical union. The craters of Mercury
have to be named for dead artists, painters, musicians, or authors,
while only the dead and famous get moon craters named after them.
Asteroids can be named after regular folks but there are so many
restrictions it rarely happens.

"The problem is that these companies are out there making a profit and
people think they are for real. They lead people to think they are
actually naming a star," said Dan Green, an astronomer with the
Smithsonian Astrophysical Observatory in Cambridge. The astronomical
union's Web site jokingly urges potential star buyers to visit the real
estate they are buying before forking over money.

"A lot of people buy these stars for sentimental reasons for people who
are dying or who died. Give the money to the American Cancer Society,''
he said. "It will be better spent."

Novelty, not science, is the star-naming companies' defense. They say
it is a gag gift that translates only into a certificate, a name in a
database, and a huge smile.

"It's a novelty gift and that's all,'' said Cort Vaughan, of Name a
Star in Oregon. "Even though it has no scientific basis, it's
something people love. They name them after loved ones, to commemorate

Fransen's boyfriend, Patrick McCarthy, a student at Suffolk University,
agreed. He bought her the present as a one-year anniversary gift. "I
know it's not real, the name isn't etched in stone," said McCarthy,
also from North Reading. "It's just a unique gift. She was really

Even a gag stab at eternity, however, translates into big money. While
Name a Star says it has sold about 10,000 star names since it began,
the firm is dwarfed by the International Star Registry, a conglomerate
with 15 worldwide offices that says it has named close to a million
stars. In 1998 alone, the company sold more than $4 million worth of
star names.

International Star Registry filed suit in October in Illinois Federal
Court against Name a Star, saying that the company was using its
federally registered name to sell star names on its Web site. But
International Star Registry uses the phrase `name a star' on its Web
site too. Both companies declined to discuss the lawsuit.

If the International Star Registry wins, Name a Star - which has for
now removed mention of the registry from its Web site - cannot call
itself a star registry. Without that ring of authenticity, sales could

But, while the two oldest name-a-star firms duke it out in court, new
competitors are getting in on the action - with the help of the Web.

A quick browse of the Web turned up a Universal Star Listing, Celestial
Registry, and a Ministry of Federal Star Registration, among others. A
consumer can even send $50 to a Brookfield, Mass., post office box and
Chris Schell, "astronomer since 1953," will pick a star and put it in
"Schell's Astronomical Index." He notes on the Web site, "There is
considerable work and experience involved in such an undertaking."

This story ran on page A01 of the Boston Globe on 5/1/2000.
© Copyright 2000 Globe Newspaper Company.

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please contact the moderator Benny J Peiser < >.
Information circulated on this network is for scholarly and
educational use only. The attached information may not be copied or
reproduced for any other purposes without prior permission of the
copyright holders. The fully indexed archive of the CCNet, from
February 1997 on, can be found at



     "Though these high-energy events may somehow be coupled to solar
     climate, including dust and gases from comets, they do not seem to
     be directly related to impact with a massive body. Descriptions
     like Daniel found are real teasers; not only do they sound like a
     valid impact description but it is conceivable that this type of
     phenomenon could actually occur in the wake of remote atmospheric
     impacts. In other words we need to remember that we live on the
     bottom of an ocean of air and its temperature, electrical
     potential, aerosol content, etc, influences the various stresses
     on the Earth's crust. Again--I think that we have a great deal to
     yet learn about this dynamic planet we live on as well as the
     variable environment it zooms through."
          -- Bob Kobres

    Joel Gunn <>

    Everett K. Gibson <>

    Mark Kidger <>

    Mike Baillie <>

    Bob Kobres <>


From Joel Gunn <>


I am an anthropologist and one of the things that anthropologists talk
about that might reinforce your decision to make an impact hazard scale
of 5 items (rather than 10) is what is referred to as "folk
taxonomies." Folk taxonomies are classifications of common phenomena
such a color, kinship, family history, etc. They generally consist of
around 7 categories as does color in our culture.

It seems that people as groups can learn and share a taxonomy of this
size with facility. Any system of classification that requires more
categories will become a matter of special training such as the
alphabet (26 characters), or medicinal plants, and persons mastering
these classifications will be considered specialists in the culture. 
This longstanding anthropological observation has been reinforced
recently by brain studies that find that the human brain operates on
what appear to be in effect seven short term memory locations. Thus,
most people can hold about seven or so categories in mind at the same
time and choose between them. 

Joel Gunn


From Everett K. Gibson <>

Sorry for the delay in responding but I have been in the UK for the
past three weeks. Here is a brief response to the inquiry:

Mars is believed to have had a weak magnetic field during the first
0.5-0.7Ga of its history (Data published in SCIENCE, 1999. Data
obtained from magnetometer onboard orbiting spacecraft currently in
orbit about Mars). The magnetites which we see in ALH84001 carbonate
rims are those which have the unusual biogenic properties. The
carbonates containing the magnetites have been age dated via Rb-Sr and
Pb-U techniques to be 3.9 Ga age. The magnetites which we believe have
biogenic properties (i.e. those formed from magnetotactic bacteria)
were formed during a period of time when the planet had a weak magnetic

Everett K. Gibson


From Mark Kidger <>

Dear Beny:

I would like to pick up E.P. Grodine's caution in CCNet-Letters.
Reading CCNet over the last few months one is struck by just how many
possible NEO impact events can be found in historical records - even in
recent centuries. This is slightly worrying as the much lower human
population density a few centuries ago and even more so further back,
would mean that most impact events would be missed because they would
have occurred in uninhabited regions, or regions where there is little
or no written history.

It might be a salutory excercise to calculate just how many important  
events would be predicted over, for example, the last three millenia
and, from the variation in population distribution and density, just
how many of these events might have been expected to be observed and

My intuitive feeling is that there are more candidate events than one
might reasonably expect, in which case it will be necessary to look for
additional criteria to distinguish candidate impacts from other events.

Mark Kidger


From Mike Baillie <>

Hi Benny,

Ed Grondine makes some useful points in his NOT ALL BRIGHT LIGHTS IN
THE SKY WERE IMPACTORS piece, not least about religious supression. 
However, I think yet again it is worth mentioning that we have a global
environmental event to explain at around AD 540. An event pointed out
by tree-ring records not by human history. Bright lights may be as good
a clue as to cause as anything else.

I would like to take issue with Ed on the subject of dragons. Ed wrote:
"Yet another trap for those working with ancient records is working out
of context, which can lead to errors in working with inadequate
translations by earlier writers. For example, if memory serves me
correctly, 'draigne', sometimes translated into Welsh as 'dreic',
'dragon', is an early Anglo-Saxon title. Particular caution should be
made with mentions of dragons in the work of Geoffrey of Monmouth."

Now I am not a linguist or a wordsmith or a mythologist, so I have to
assume that people who trade in those disciplines have some inkling of
what they are talking about.  Every translation of Beowulf talks about
a fire-dragon, right up to Seamus Heaney 1999.  Beowulf is pretty
closely confined to the early sixth century by writers who from their
credentials should have known what they were talking about.
Merlin, the universally accepted side-kick of Arthur, which just about
everyone would place in the sixth century is associated with dragons by
writers like Nikolai Tolstoy. Anyone who cares to dig out his 'The
Quest for Merlin' (Hamish Hamilton 1985) and leaf through to page 113
will get a hint of the background to dragons largely independent of
Geoffrey of Monmouth. 

Basically, in order to answer the question whether there was a
bombardment event around AD 540, we need some hard scientific evidence
from an encapsulated deposit be it an ice core or a tree ring record or
a peat deposit or a varve series. The dragons and the bright lights in
the sky give us a pretty good clue what the answer will be; they cannot
in themselves supply that answer.

Mike Baillie


From Bob Kobres <>

Regarding the 1822 event reported by Daniel Fischer (CCNet 04/26/00). 
The description is similar to reports of a luminous body and heated air
observed in 1737:


"6) This meteor was seen at Venice at the same time; and, over Kilkenny
in Ireland, it appeared like a great Ball of Fire; which burst with an
Explosion that shook [a] great Part of the Island, and set the whole
Hemisphere on Fire; which burnt most furiously, till all the
sulphureous Matter was spent."

Point five is also intriguing:

"5) The whole Time was attended with an extraordinary Heat of the Air
for the Season [early December]; for I was obliged to strip to the
Shirt, though abroad in the Air all the time."

Though these high-energy events may somehow be coupled to solar
climate, including dust and gases from comets, they do not seem to be
directly related to impact with a massive body. Descriptions like
Daniel found are real teasers; not only do they sound like a valid
impact description but it is conceivable that this type of phenomenon
could actually occur in the wake of remote atmospheric impacts.  In
other words we need to remember that we live on the bottom of an ocean
of air and its temperature, electrical potential, aerosol content, etc,
influences the various stresses on the Earth's crust.  Again--I think
that we have a great deal to yet learn about this dynamic planet we
live on as well as the variable environment it zooms through. 



Heresy (;^) from:

This www-page is devoted to the phenomenon, which can be called
"geophysical meteors" (or "geometeors"). They are meteor-like luminous
events, but of none-meteoroidal (i.e. terrestrial) origin. Just two
centures ago every meteor was thought to be of terrestrial origin, as
"stones can not fall from the sky", and those few, who said about
stones fallen from the sky considered as heretics.

Then it was discovered that stones can fall, and they are of
extraterrestrial origin (meteorites). The previous dogma was quickly
forgotten, so the pendulum has swung into the extreme opposite
position, and a new dogma was born declaring that every
fireball/meteor/bolide in the sky is of meteoroidal origin, and is
caused by a chunk of extraterrestrial rock/ice, etc., or, at least,
manmade space debris.

Just recently, the pendulum began to move to the equilibrium position.
An article on the item appeared even in astronomical journal
METEORITICS & PLANETARY SCIENCE (you can read the scanned article).

It seems that the Nature used to keep the Truth in between!

The main problem with geophysical meteors (geometeors) is that, unlike
the meteoroidal meteors (astrometeors), their physical mechanism is not
known. We can just suppose that probably the origin has some
resemblance with a ball-lightning. But the latter one is a problem for
modern scientists too! Many scientists try to avoid the problem, just
ignoring it, while groups (not very large) of enthusiasts work hard
over it. Wish them a success!

Let's return to geometeors. Several examples of them can be found in my
tectonic Tunguska article. New ones are given below. But I will begin
with discussion of their possible physical mechanisms.



Purported images of 'earthquake lights' along fault in Turkey:


Observations collected by Charles Hoy Fort:


Feb. 2, 1816 -- a quake at Lisbon. There was something in the sky.
Extraordinary sounds were heard, but were attributed to "flocks of
birds." But six hours later something was seen in the sky: it is said
to have been a meteor (Rept. B.A.,, 1854-106).(12) [94/95]

Since the year 1788, many earthquakes, or concussions that were listed
as earthquakes, had occurred at the town of Comrie, Perthshire,
Scotland. Seventeen instances were recorded on the year 1795. Almost
all records of the phenomena of Comrie start with the year 1788, but,
in Macara's Guide to Creiff, it is said that the disturbances were
recorded as far back as the year 1597.(13) They were slight shocks, and
until the occurrence upon August 13, 1816, conventional explanations,
excluding all thought of relations with anything in the sky, seemed
adequate enough. But, in an account in the London Times, Aug. 21, 1816,
it is said that, at the time of the quake of Aug. 13, a luminous
object, or a "small meteor," had been seen at Dunkeld, near Comrie;
and, according to David Milne, (Edin. New Phil. Jour., 31-110), a
resident of Comrie had reported "a large luminous body, bent like a
crescent, which stretched itself over the heavens."(14)

[Lots of quartzite in these parts.  bobk]


There was another quake in Scotland (Inverness) June 30, 1817. It is
said that hot rain fell from the sky (Rept. B.A., 1854-112).(15)

Jan. 6, 1818 -- an unknown body that crossed the sun, according to
Loft, of Ipswich; observed about three hours and a half (Quar. Jour.
Roy. Inst., 5-117).(16)

Five unknown bodies that were seen, upon June 26, 1819, crossing the
sun, according to Gruithuisen (An. Sci. Disc., 1860-411).(17) Also,
upon this day, Pastorff saw something that he thought was a comet,
which was then somewhere near the sun, but which, according to Olbers,
could not have been the comet, (Webb, Celestial Objects, p.40).(18)

Upon Aug. 28, 1819, there was a violent quake at Irkutsk, Siberia.
There had been two shocks upon Aug. 22, 1813 (Rept. B.A.,
1854-101).(19) Upon April 6, 1805, or March 25, according to the
Russian calendar, two stones had fallen from the sky at Irkutsk (Rept.
B.A., 1860-12).(20) One of these stones is now in the South Kensington
Museum, London.(21) Another violent shock at Irkutsk, April 7, 1820
(Rept. B.A., 1854-128).(22)

Unknown bodies in the sky, in the year 1820, Feb. 12 and April 27
(Comptes Rendus, 83-314).(23)
Things that marched in the sky -- see Arago's uvres, 11-576, or Annales
de Chimie, 30-417 -- objects that were seen by many [95/96] persons, in
the streets of Embrun, during the eclipse of Sept. 7, 1820, moving in
straight lines, turning and retracing in the same straight lines, all
of them separated by uniform spaces.(24)

Early in the year 1821 -- and a light shone out on the moon -- a bright
point of light in the lunar crater Aristarchus, which was in the dark
at the time. It was seen, upon the 4th and the 7th of February, by
Capt. Kater (An. Reg., 1821-689); and upon the 5th by Dr. Olbers (Mems.
R.A.S., 1-159).(25) It was a light like a star, and was seen again, May
4th and 6th, by the Rev. M. Ward and by Francis Bailey (Mems. R.A.S.,
1-159).(26) At Cape Town, nights of Nov. 28th and 29th, 1821, again a
star-like light was seen upon the moon (Phil. Trans., 112-237).(27)

Quar. Jour. Roy. Inst., 20-417:(28)
That, early in the morning of March 20, 1822, detonations were heard at
Melida, an island in the Adriatic. All day, at intervals, the sounds
were heard. They were like cannonading, and it was supposed that they
came from a vessel, or from Turkish artillery, practicing in some
frontier village. For thirty days the detonation continued, sometimes
thirty or forty, sometimes several hundred, a day.

[Likely related to the attack on Chios.  bobk]

Upon April 13, 1822, it seems, according to description, that clearly
enough was there an explosion in the sky of Comrie, and a concussion of
the ground -- "two loud reports, one apparently over our heads, and the
other, which followed immediately, under our feet" (Edin. New Phil.
Jour., 31-119).(29)

July 15, 1822 -- a fall of perhaps unknown seeds from perhaps an
unknown world -- a great quantity of little round seeds that fell from
the sky at Marienwerder, Germany. They were unknown to the inhabitants,
who tried to cook them, but found that boiling seemed to have no effect
upon them. Wherever they came from, they were brought down by a storm,
and two days later, more of them fell, in a storm, in Silesia. It is
said that these corpuscles were identified by some scientists as seeds
of Galium spurium, but that other scientists disagreed. Later more of
them fell at Posen, Mecklenburg. See Bull. des Sci. (math., astro.,
etc.) 1-1-298.(30)

Aug. 19, 1822 -- a tremendous detonation at Melida -- others continuing
several days.(31) [96/97]

Oct. 23, 1822 -- two unknown dark bodies crossing the sun; observed by
Pastorff (An. Sci. Disc., 1860-411).(32)

12. Robert Mallet. "Third report on the facts of earthquake phenomena."
Annual Report of the British Association for the Advancement of
Science, 1854, 1-326, at 106. The "meteor" was observed immediately
after the first shock of the earthquake, (not "six hours later," when
another series of less intense shocks were felt).

13. Duncan Macara. Macara's Guide to Creiff, Comrie, St. Filans, and
Upper Strathearn.... Edinburgh: D. Macara, (189-?).

14. "Earthquake in Scotland." London Times, August 21, 1816, p.3 c.2-3.
Dunkeld is about 35 kilometers from Comrie. David Milne. "Notices of
earthquake shocks felt in Great Britain, and especially in Scotland,
with inferences suggested by these notices as to the causes of such
shocks." Edinburgh New Philosophical Journal, 31 (1841): 92-122,
259-309, at 117.

15. Robert Mallet. "Third report on the facts of earthquake phenomena."
Annual Report of the British Association for the Advancement of Science,
1854, 1-326, at 112. "Meteorological retrospect for the last half of the
year 1817." Philosophical Magazine, 51 (January to June, 1818): 189-99,
at 193.

16. "Supposed transit of a comet." Quarterly Journal of the Royal
Institute of Great Britain, 5 (1818): 117-8. The object was observed by
Lofft for more than three-and-a-half hours. For Lofft's original
report: Capel Lofft. "On the appearance of an opaque body traversing
the sun's disc." Monthly Magazine, o.s., 45 (March 1, 1818): 102-3.

17. "New planets." Annual of Scientific Discovery, 1860, 409-11, at
411. Three, not five, "solar spots" were observed "...viz., one near
the middle of the sun, and two small one without nebulosity near the
western limb."

18. Thomas William Webb. Celestial Objects. 4th ed. 1881. 6th ed.,
1917. 4th ed., 40.

19. Robert Mallet. "Third report on the facts of earthquake phenomena."
Annual Report of the British Association for the Advancement of Science,
1854, 1-326, at 101, 125.

20. R.P. Greg. "A catalogue of meteorites and fireballs, from A.D. 2 to
A.D. 1860." Annual Report of the British Association for the
Advancement of Science, 1860, 48-120, at 62.

21. Lazarus A. Fletcher. Introduction to the Study of Meteorites....
1904. 10th ed., London: British Museum Trustees, 1908, 98, (notes).

22. Robert Mallet. "Third report on the facts of earthquake phenomena."
Annual Report of the British Association for the Advancement of Science,
1854, 1-326, at 128. The date of the shock was May 7, 1820, (not April

23. Le Verrier. "Examen des observations qu'on a présentées, à diverses
époques, comme pouvant appartenir aux passages d'une planète
intra-mercurielle devant le disque du Soleil." Comptes Rendus, 83
(1876): 583-9, 621-4, 647-50, 719-23; at 589, 621.

24. [Dominique] FranÇois [Jean] Arago. Oeuvres Complètes de FranÇois
Arago. Paris, 1857, v.11, 575-8. "M. Dick imagine que le phénomène
observé par M. Hansteen...." Annales de Chimie, s.2, 30 (1825): 416-21.

25. "Volcanic appearance in the Moon." Annual Register, 1821, 687-8.
The light was also seen by Kater on February 6. For the original
report: Henry Kater. "Notice respecting a volcanic appearance in the
Moon." Philosophical Transactions of the Royal Society of London, 111
(1821): 130-2, pl. X. William Olbers. "On the comet discovered in the
constellation Pegasus in 1821: and on the luminous appearance on the
dark side of the Moon on February 5, 1821." Memoirs of the Royal
Astronomical Society, 1, 156-8.

26. The observation was made on May 5, 1821, when the clouded skies
prevented Ward from viewing it. Michael Ward. "On a luminous appearance
seen on the dark part of the Moon in May 1821." Memoirs of the Royal
Astronomical Society, 1, 159-61.

27. Fearon Fallows. "Communication of a curious appearance lately
observed upon the Moon." Philosophical Transactions of the Royal
Society of London, 112 (1822): 237-8.

28. "Remarkable phenomena observed in the Island of Melida, Province of
Ragusa." Quarterly Journal of the Royal Institute of Great Britain, 20,
417-8. Fort wrote "thirty days" as the duration, though the article he
cites states "eight or nine months." "Détonations extraordinaire dans
l'île Méléda." Annales de Chimie et de Physique, s. 2, 30 (1825):

29. David Milne. "Notices of earthquake shocks felt in Great Britain,
and especially in Scotland, with inferences suggested by these notices
as to the causes of such shocks." Edinburgh New Philosophical Journal,
31 (1841): 92-122, 259-309, at 119.

30. The seeds fell at Posen and the country around Mecklenburg). Kreis.
"Effet remarquable d'un orage." Bulletin (Universal) des Sciences,
Mathematiques, Astronomique, Physiques et Chimiques, 1 (1824): 298-9.

31. "Détonations extraordinaire dans l'île Méléda." Annales de Chimie
et de Physique, s. 2, 30 (1825): 432-5. The date of the phenomenon was
August 10, 1822, (not August 19).

32. "New planets." Annual of Scientific Discovery, 1860, 409-11, at


In 1783 and 1787, Herschel reported more lights on or near the moon,
which he supposed were volcanic.(43)

The word of a Herschel has had no more weight, in divergences from the
orthodox, than has had the word of a Lescarbault. These observations
are of the disregarded.

Bright spots seen in the moon, Nov., 1821 (Proc. London Roy. Soc.,

For four other instances, see Loomis ("Treatise on Astronomy," p.

A moving light is reported in Phil. Trans., 84-429.(46) To the writer,
[198/199] it looked like a star passing over the moon -- "which, on the
next moment's consideration I knew to be impossible." "It was a fixed,
steady light upon the dark part of the moon." I suppose "fixed" applies
to luster.

In the Report of the Brit. Assoc., 1847-18, there is an observation by
Rankin, upon luminous points seen on the shaded part of the moon,
during an eclipse.(47) They seemed to this observer like reflections of
stars. That's not very reasonable: however, we have, in the Annual
Register, 1821-687, a light not referable to star -- because it moved
with the moon: was seen three nights in succession; reported by Capt.
Kater.(48) See Quar. Jour. Roy. Inst., 12-133.(49)

Phil. Trans., 112-237:(50)
Report from the Cape Town Observatory: a whitish spot on the dark part
of the moon's limb. Three smaller lights were seen.

43. Wilhelm Herschel. Philosophical Transactions of the Royal Society
of London, 77, 229. On October 22, 1790, Herschel reported seeing as
many as one-hundred-and-fifty "bright, red, luminous points" upon the
eclipsed moon; but, he was more cautious in 1791, and saying "we know
too little of the surface of the moon," he would not "venture to
surmise" their cause. Wilhelm Herschel. "Miscellaneous observations."
Philosophical Transactions of the Royal Society of London, 82 (1792):
23-27, at 27.

44. Fearon Fallows. "Communication of a curious appearance lately
observed upon the Moon." Proceedings of the Royal Society of London, 2,
167. The observations were made upon November 28 and 29, 1821.

45. Elias Loomis. A Treatise on Astronomy. New York: Harper & Brothers,
1881, 174-5. These other observations were all made during solar
eclipses: June 24, 1778, by Ulloa; May 15, 1836, by Bessel; July 8,
1842, by Valz, at Marseilles; and, July 18, 1860, by two Frenchmen,
(Bout and Mannheim), in Algeria. T.W. Webb. Celestial Objects for
Common Telescopes. 4th ed. London: Longmans, Green and Co., 1881, 76-7.
Webb mentions that Gruithuisen believed he had seen the "specks of
light," also reported by Schröter; and, "with great distinctness," Webb
says they were observed by Grover and Williams.

46. "An account of an appearance of light, like a star, seen in the
dark part of the Moon, on Friday the 7th of March, 1794, by William
Wilkins, Esq. at Norwich." Philosophical Transactions of the Royal
Society of London, 84, 429-40, at 430. The correct quote is from the
article's title, thus: " the dark part...." The observation was
made upon March 7, 1794, for about five minutes before the light

47. T. Rankin. "On a singular appearance of the shaded part of the
Moon...." Annual Report of the British Association for the Advancement
of Science, 1847, trans., 18.

48. "Volcanic appearance in the Moon." Annual Register, 1821, 687-8.

49. Henry Kater. "Notice respecting a volcanic appearance in the Moon,
in a letter addressed to the President." Quarterly Journal of the Royal
Institute of Great Britain, 12, 133. For the original report and
illustration: Henry Kater. "Notice respecting a volcanic appearance in
the Moon, in a letter addressed to the President." Philosophical
Transactions of the Royal Society of London, 111 (1821): 130-3, pl. X.

50. Fearon Fallows. "Communication of a curious appearance lately
observed upon the Moon." Philosophical Transactions of the Royal
Society of London, 112 (1822): 237-8.

Comet Encke was showing its tail a bit more around this time period. 

During 1821 Johann Franz Encke published his prediction that Pons comet
of 1819 would return to perihelion 1822 May 23.63, which was just one
day too early. Further investigations of this comet's orbit in 1823 led
Encke to the conclusion that the comet had also been detected in 1786,
1795, and 1805.

Magnitude estimates were not made until the late 19th century, but
astronomers have attempted to determine the maximum brightness of this
comet at each of its returns. It seems apparent that the comet has
faded since 1786. The greatest recorded brightness was about 3.5 in
1829, while a value of 4.0 was indicated in 1805. The comet has not
been observed as brighter than magnitude 5.0 during the 20th century. A
magnitude of 5.0 was last registered in 1964.

A few links regarding the geology of the general area:


Bob Kobres
Main Library
University of Georgia
Athens, GA  30602

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