PLEASE NOTE:
*
CCNet, 43/2000 - 4 April 2000
-----------------------------
"At least NASA's planning for Earth
science is done by a somewhat
rational method. The second paper was by
Marc S. Allen, who
explained that instead of setting space
science plans by using any
type of cost-benefit analysis, NASA set
space science plans by
‘theme’. Asteroid and cometary
impacts are not currently a NASA
‘theme’, but instead fall
under ‘Our Solar System’. During the
question and answer period I asked Allen
about the funding levels
for NEO searches, and he told me he had
no idea what they were.
Following up on this later, he told me
the amount was so small as
to be beneath his notice.”
-- Ed Grondine,
4 April 2000
(1) REPORT FROM THE AMERICAN ASTRONAUTICAL SOCIETY'S
38th GODDARD MEMORIAL SYMPOSIUM
E.P. Grondine <epgrondine@hotmail.com>
(2) WILL A KILLER ASTEROID HIT THE EARTH?
Robert Clements <Robert.Clements@dva.gov.au>
(3) NEAR SHOEMAKER SCIENCE UPDATE
Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
(4) SPACE DUST MEETING IN THE UK
Peter Bond <100604.1111@compuserve.com>
(5) WHERE IS THE MARTIAN MAGNETIC FIELD FOR
MARTIAN MAGNETOTACTIC BACTERIA?
Gerrit Verschuur <GVERSCHR@LATTE.MEMPHIS.EDU>
(6) NEOS & THE IMPACT HAZARD VIEWED FROM VIENNA
Giesinger Norbert <norbert.giesinger@siemens.at>
(7) AND FINALLY: INFORMATIZATION IS MAKING CIVILISATION FAIRER
H. Cleveland, UNIVERSITY OF MINNESOTA
========
(1) REPORT FROM THE AMERICAN ASTRONAUTICAL SOCIETY'S
38th GODDARD MEMORIAL SYMPOSIUM
From E.P. Grondine <epgrondine@hotmail.com>
Hello Benny -
Last Wednesday and Thursday I attended the American Astronautical
Society's 38th Goddard Memorial Sympoisum. I must apologize for
being so late in getting this report to you, but the diverse
materials and impressions I gathered there present no easy means
of organization. Some historians argue that history should be
presented by themes, and following this line of thinking the
themes here would be future US space science plans, long term
climate studies, the failure of the Mars Polar Lander and Mars
Climate Orbiter probes, and the consequences of the present
general ignorance of impact hazard. But I think that while
maybe
you can organize life by themes, life itself does not organize
itself by themes, but instead passes through time, so once again
I
will relay events chronologically.
WEDNESDAY MORNING
I must confess to a bias up-front. Of all the US space
organizations, I
like the American Astronautical Society the best. Founded back in
the
glory days of manned space exploration, the AAS is now is
becoming
older and grayer, or more experienced and wiser, as I like to
think.
While some space organizations have more appeal to youth, it's
hard to
find a higher concentration of practicing space engineers and
scientists than at an AAS meeting, and at some point the best of
the
younger engineers always manage to show up as well.
Several years ago the AAS moved their annual Goddard symposia
from a
hotel in downtown Washington out to a hotel in suburban
Greenbelt,
close to NASA's Goddard research centre. As I understand
it, the AAS
did this so that they could spend the decrease in hotel charges
on
other things, but it has also had the effect of leaving some of
the
space business and public relations folks behind, and further
increasing the scientific focus of the annual symposia. Several
years
back NASA's "Search for Life" 'theme' was first
publicly shown at a
Goddard symposia, and undoubtedly the items discussed at this
year's
symposia will form a future focus for NASA research.
If the attendee's current awareness of the impact hazard is any
indicator, it's going to be many years before "Planetary
Defense"
becomes a NASA "theme". The only presentation related
to impacts was by
Douglas Erwin of the Smithsonian, about which more later. My own
mentions of deaths by impact were met by all as their first
knowledge
of such a phenomena. And who can blame them? Monday I recieved
notice
of Alan Alford's new book, apparently a combination of genuine
impact
tales, new-age religious claptrap, and absolutely horrid
astro-physics,
such as the explosion of "Planet-X" in historical times
giving rise to
meteorites and asteroids. Finally, we have absolute proof of
re-incarnation, as who else but Velikovsky himself could come up
with
such a work?
I arrived in Greenbelt at 6 AM Wednesday morning, and refreshed
by a
peaceful two and one half hours of sleep in my car, I got up and
fueled
myself with coffee for the morning's sessions. The first
presentation
was by a member of the Mars loss report board, who concluded that
both
JPL and Lockheed Martin had extended the definition of
"acceptable
risk" too far. NASA had extended "acceptable risk"
to include the loss
of less expensive spacecraft in hazardous terrain, or the loss of
spacecraft in the testing of new technologies, but had not
intended for
"acceptable risk" to include less than full design and
testing. I think
that while that's certainly a good way of describing what went on
during the events leading up to the Mars probes' losses, it does
little
to explain them.
The first paper was by Jack Kaye on Earth science strategic
planning,
and he set out a crude form of cost-benefit analysis, in which
weights
were given to specific research goals, and missions judged
against
those goals. Knowledge of aerosols (read "freon") and
global warming
were set out as goals, and given fairly high weights, no doubt
reflecting in some ways Vice President Gore's concerns. As will
be seen
from later presentations there is good reason to suspect that the
weights given to those particualr matters may be off a little.
At least NASA's planning for Earth science is done by a somewhat
rational method. The second paper was by Marc S. Allen, who
explained
that instead of setting space science plans by using any type of
cost-benefit analysis, NASA set space science plans by
"theme".
Asteroid and cometary impacts are not currently a NASA
"theme", but
instead fall under "Our Solar System". During the
question and answer
period I asked Allen about the funding levels for NEO searches,
and he
told me he had no idea what they were. Following up on this
later, he
told me the amount was so small as to be beneath his notice.
Lest you're too baffled by this, allow me to explain. Here we
need to
follow good anthropological technique and look at behaviour, and
not at
peoples' explanations of their behaviour, applying the technique
in
this instance to NASA's behaviour. Private companies stopped work
on US
launchers when work began on the shuttle. After the Challenger
disaster, the Reagan administration encouraged private companies
to
re-enter the launch market, and they did so with launch vehicles
of
1950's design which were dreadfully expensive to operate and
seriously
under capacity for launching communication satellites. NASA then
began
to launch small probes to aboard these companies small launchers,
thus
providing them with a market.
Hence you have large expenditures on probles to asteroids and
comets,
with very little spent on NEO detection. This same principle was
relfected in a presentation after lunch where Louis Uccelli of
the
National Weather Service stated their pressing need for more
computers.
If the analysis is correct, we will see the US government spend
money
on additional launches of weather research satellites instead of
on
these computers.
WEDNESDAY LUNCH
At lunch I shared a table with Yasunori Iwana of Japan's NASDA,
who may
have been the only individual at the symposium with any idea of
the
severity of the impact hazard. I spoke to him about my work with
the
Ainu folk tales, and apologized that my complete lack of Japanese
meant
that I myself could carry it out no further. Yasunori told me
that
other impact tales were recorded in the most ancient Japanese
writings,
and suggested that Dr. Isobe might be able to make English
translations
available. I expressed my reservations that all of Dr. Isobe's
time
would be completely required in making observations with the new
Japanese NEO telescope.
Yasunori commented on how wide spread was modern Japanese amateur
interest in astronomy, and noted that this continued the ancient
tradition of observations of the sky. Given the prevalent
Japanese
religion, which is a combination of shinto and budhism, this
comes
as no surprise. I commented to Yasuori as to how the United
States
was a young nation, with no ancient traditions. Later, reflecting
further on this, Benny, I may have discoverd the fundamental
reason for
the difference between US and British estimate of the impact
hazard. In
the US, history begins a little over 225 years ago, and popular
historical awareness extends back only to the last television
season.
In the UK, history goes back 6,000 years, and students have to
know
most of the facts concerning it just to graduate high school [you
wish!, BJP].
The luncheon speech was by Arthur Poland, who used one of the new
computer projection systems from Sanyo to give a magnificant
presentation on the variabilty of our sun. These computer
projection
systems are goin to make overhead projectors and slides a thing
of the
past. Controling the computer was a problem, and there is a real
need
for a hand held touch-pad mounted on a grip and linked to the
computer
by infra-red. Timo Niroma will be pleased to know that during the
question period I asked Poland if he was aware of any studies
tying
solar variability to the effects of Jupiter's gravity. He told me
no,
and we discussed this further at the reception, of which more,
later.
WEDNESDAY AFTERNOON
The afternoon's session was related to a new NASA initiative, or
"theme", living with a variable star. Judith Lean of
the Naval Research
Laboratory presented the exciting results of a colloqium held two
weeks
ago, in which a mechanism tying solar variablilty to climate
change was
refined. Not surprisingly, she had also reached the same
conclusion
that Timo did earlier that the effects of CFC and CO2 were not as
bad
as once suspected.
None of the presenters were aware of the work on sunspots and
weather
which had been done by Fr. John Ricardo, the "Padre of the
Rains", at
the Univeristy of Santa Clara at begining of the last century.
Someday,
I'd like to see a satellite named after him.
Other problems from solar variability were presented by Mike
Bonadonna,
Chief, Space Weather Plans, United States Air Force Directorate
of
Weather. It turns out that besides interfering with
communications,
electronic equipment operation, and satellite operations,
increased EMF
also throws off the GPS targeting system, giving wrong positions
by
"bending" the GPS signals. Bonnadonna estimated
current US Department
of Defense expenditures in dealing with all of these problems at
$500
million per year.
Further US military goals were evident but not as clearly set out
in
several papers presented Thursday afternoon on the use of
distributed
satellite networks for scientific work. That the same
technologies,
i.e., on orbit co-ordination and replacement, partial system
functioning, intelligent messaging systems, etc. which are needed
for
these scientific satellites are also needed for a functioning
ballistic
missile interception system is clear. In the years ahead we can
expect
to see placed in operation distributed systems of small
satellites for
monitoring the Sun-Earth environment.
WEDNESDAY'S RECEPTION
Moving on to Wednesday's reception, I picked up my exchange with
Art
Poland on Jupiter and solar cycles and informed him of Timo's
work. He
expressed scepticism that Jupiter's gravity would be strong
enough to
affect the sun's nuclear reaction, and seemed to favor shearing
forces
from rotation. I myself don't know if the Sun's rotation matches
Jupiter's orbital movements, so correlation instead of causality
may be
possible here.
I also had a chance to speak with Dr. Wesley Huntress, who
presided
over the symposia. Dr. Huntress was clearly upset about the loss
of
Mars Polar Lander and Mars Climate Orbiter, and I expressed my
sympathy. Dr. Huntress pointed out to me that the mistakes which
had
been made with both probes were stupid mistakes, that people make
stupid mistakes when they're under pressure, and that what the
loss
meant to him was that NASA was an organization under pressure.
When I
interviewed Lockheed Martin's Noel Hinners in depth after his
final
presentation on the loss on Thursday I confirmed that Dr.
Huntress was
correct in his assessment.
THUSDAY MORNING
An allergy attack weigh-layed me from the first of Thursday's
presentations, but I did arrive in time for "600 Million
Years of
Mass Extinctions" by Douglas Erwin of the Smithsonian. Erwin
is
attempting to work through extinctions in a rigourous manner, and
he placed a large amount of emphasis on volcanic activity instead
of impact. This is not too surprising, as he seemed to not be
aware of
some of the more recently discovered craters. Among other causes
of
extinction Erwin listed sea level changes, glaciation, and
methane
eruptions. Erwin described the well know 26 million year cycle as
something of an artifact. He also concentrated on the continuity
of
life, and recovery, and pointed to the dominance of some life
forms
despite setbacks.
Erwin attributed the Permian-Triassic extinction to Siberian
volcanic
eruptions, and seemed not to know of the South Atlantic craters.
(Benny, I hope my memory has not failed me here). During the
question
period I asked Erwin whehter he thought that an impact could have
TRIGGERED the Siberian eruptions, and he replied that an impact
sufficient to have CAUSED that Siberian traps would have torn the
Earth
apart. Perhaps if I had of asked Erwin if an impact could have
TRIGGERED EXISTING FAULTS my question would have been clearer.
In any case, it's going to be interestiong to see whether or not
the
350 - 1,000 megaton Rio Cuarto impact triggered the nearby active
Andean fault system, as I seem to recall that excavations are
currently
underway to determine the dates of seismic activity in the Andean
system. Evidence from the Rio Cuarto event on the differences
between
atmoshperic dust loading from impact versus volcanos may also
help to
resolve Baillie and Keys' differences over the cause of the
mid-sixth
century catastrophes. In the end, Erwin seemed to me to be of
good
temper and sound mind, and I think that he will play an important
role
in sorting out the causes of the different extinctions.
THURSDAY LUNCH
The next speaker was Charles Delwiche of the Univeristy of
Maryland,
and he presented his fascintating work on rates of genetic
change.
These rates have been thought to be roughly constant over time,
as is
the background radiation to which these genetic changes are
ascribed.
Delwiche has been studying parts of cells which are remnants of
earlier
organisms which have been absorbed by their contemporaries, and
so on
and so on over the millenia. For example, malaria actually
contains
part of a plant, and current treatments based on herbicides are
being
experimented with. To give you an idea of the value of Delwiche's
work,
every day something like sixteen 747-plane loads of people die
from
malaria.
I have no skills in biology, so I hope I'm not mistating things
here,
but in Delwiche's studies, the emergence of organisms which have
absorbed other organisms seems to be tied to extinction events,
and the
rate of genetic change no longer appears constant. I joined
Delwich at
lunch, and we discussed organisms that have incorporated part of
early
cyano-bateria, the "red tide" which occurs in the
Chesapeake Bay, and
pfisteria, which is becoming a major health hazard in North
Carolina.
Delwiche feels that North Carolina needs to get its algae growth
under
control, as this is the pfisteria's food. I also learned that
ther are
contacts between Delwiche and John Rummel of NASA's Planetary
Protection Office, and my congratulations to Rummel on this. If
there
is anyone I'd want working on Martian life, it's Delwiche, but
his work
with Earth organisms is so important that I'm almost afraid to
see him
distracted.
The Thursday luncheon speaker was Steven Isakowitz of the White
House's
Office of Management and Budget. If I had to sum up Isakowitz's
talk in
a very few words, they would be "Democrats good, Republicans
bad".
Isakowitz mentioned that Vice President Gore had worked closely
with
the OMB on the NASA budget as Gore had a great interest in it,
and
Iskowitz feared that another space science budget showdown like
last
years would occur again this year.
THURSDAY AFTERNOON AND EVENING:
WHAT HAPPENED TO MARS POLAR LANDER AND MARS CLIMATE ORBITER?
I mentioned Thursday afternoon's papers on distributed satellite
systems earlier, and Thursday afternoon's second session papers
on
methods of sharing limited engineering talents will be of little
interest. I think you'll be far more fascinated with what I
gathered
from Lockheed Martin's Noel Hinners on the loss of Mars Polar
Lander
and Mars Climate Orbiter.
The immediate cause of the loss of both spacecraft were computer
engineering glitches: a programmer did not look at the data
definition
tables for Mars Climate Orbiter, and other electronic engineers
failed
to re-validate and re-verify the lander leg control routines
after
landing leg sensor mis-wirings had been corrected. Hinners spoke
at
length about the difficulties in competing with internet
companies for
the available computer engineers.
- Why hadn't Lockheed Martin hired more computer engineers?
Hinners
told me that the hardware had arrived late, and that the need for
more
of them hadn't become visible until then.
- Why had the hardware arrived late? Speaking later with a
hardware
supplier, I learned that Lockheed Martin had bid the contracts so
low
that they went to the cheapest hardware suppliers, who also
turned out
to be the least experienced, and who had only been able to
deliver
their hardware late.
- Even so, why hadn't Lockheed Martin hired more computer
engineers?
Hinners had gone to Ed Stone of JPL and asked for more money, but
Dr.
Stone had turned him down.
- Why did an experienced manager like Dr. Stone turn down
Hinner's
request? Here Dr. Huntress's observations come into
play: NASA was an
organization under stress.
- Why was NASA under stress? The immediate cause of NASA's stress
may
be found in the miserable performance Yuri Pavlovich Semenov in
running
the Russian firm NPO Energia, and in particular his miserable
performance in delivering the Service Module for the
International
Space Station in a timely manner. (My opinion is that Putin needs
to
fire Semenov for trying to sell to the Chinese technology with
military
applications. NPO Energia has many qualified managers capable of
running it better than Semenov, and a nuclear exchange between
the
mainland and Taiwan is not in Russia's interest, as it would
cripple
the economy and the people in Russia's Far East.)
- Why did Energia's failure become such a source of stress for
NASA?
Here, the Republican Party's tactic of "attack
politics" comes into
play. When Clinton took over the office of President, his team
had left
a secretary who had been hired during Bush's term working in the
office
of his lawyer. She had passed on to some Republicans all
information on
possible legal matters affecting Clinton, and they had used this
information to mount multiple attacks against him.
- Why were attack politics extended to the US space program?
Here, NASA
had long been under attack by the Space Frontier Foundation, who
believe that NASA should cancel the shuttle, cancel the space
station,
and devote all its resources to a manned Mars mission. There was
a
meeting of attacks, those of the Space Frontier Foundation and
"mars
enthusiasts", and those of the Republican attack wing. (That
Russian
involvement in the International Space Station began with
President
Bush is an unfortunate fact which these people choose to ignore.)
To further increase pressure, the Republcans had set tight limits
on
the NASA budget. In response to the situation, NASA had moved its
reserve funds to a central account, instead of allocating them by
project, as it had done before. That is why Dr. Stone turned down
Hinners' request.
Given the lack of funds, Hinners hired less experienced computer
engineers, and he spoke at length about the amount of time it had
required to bring these computer programmers and engineers up to
speed.
Hinners observed that the military can always get skilled people
(from
the Air Force academy), but NASA and private industry are left in
the
lurch. Would a check list have helped? No - every space
science
platfrom is unique. Hinners had thought that they had sent good
spacecraft to the launch pad.
Why didn't JPL detect that the spacecraft were not good
spacecraft, but
instead hid fatal flaws? There had been so much commonality in
the
components of the two spacecraft, that JPL had combined both
platforms'
management. JPL had also done this as a way of sharing its
limited
manpower. With no one intimately familiar with the two
spacecraft, and
thus able to spot their flaws, they crashed and burned.
I pointed out to Hinners that at least no one had died, and
shared with
him that these type of computer engineering constraints are much
more
common within NASA than is known. I thanked him, expressing the
hope
that his experience may prove of some benefit to the misson
scientists
who participate in the Conference, and he seemed to take some
comfort
in this.
Well, Benny, that's it for now.
Best wishes -
Ed
================
(2) WILL A KILLER ASTEROID HIT THE EARTH?
From Robert Clements <Robert.Clements@dva.gov.au>
CNN/Time ran a piece on impactors as part of its Visions 21
series on
Sunday 2 April 2000. Not bad; but i'd be more comfortable with
the
advocacy of nuclear weapons as deterrents if i was sure that the
analysis was based on dealing with near-term threats (say, less
than
100y) rather than a generic approach.
No transcript is currently available from
http://www.cnn.com/TRANSCRIPTS/impc.html;
but i assume one will be
released shortly. Both CNN & Time have supporting articles on
their
websites... urls & texts follow.
All the best,
Robert Clements <Robert.Clements@dva.gov.au>
http://www.cnn.com/CNN/Programs/cnntime/
Will A Killer Asteroid Hit the Earth?
In 1801, an Italian astronomer peering into the night sky sighted
an
unknown object hurtling through space. He thought it was a
planet,
which he named Ceres, but it was in fact the first discovery of
an
asteroid. As modern scientists have learned more about what's out
there, a growing number are asking - in deadly seriousness: will
a
killer asteroid hit the Earth?
*
http://www.cnn.com/CNN/Programs/cnntime/archives/more_40200.html#asteroid
Will A Killer Asteroid Hit the Earth?
CNN&TIME's Jeff Greenfield
</CNN/anchors_reporters/greenfield.jeff.html> profiles a
scientist who
is trying to get some answers. Dr. Eleanor Helin, who works at
NASA's
Jet Propulsion Laboratory in Pasadena, California, is one of the
pioneers in the hunt for near-Earth asteroids. She embodies the
growing
realization among scientists and policy makers that the question
is not
If, but When? "No question about it -- that it's going to
happen," she
says. "But we have to, by going out and searching the skies,
hopefully
find this object before it finds us."
When Dr. Helin began hunting asteroids in the 1970s, she was out
of
step with colleagues who were more interested in objects farther
away
in Deep Space. "They would remark on, oh, there's these
asteroid trails
all over my photographic plates. These are the vermin of the sky.
And I
said those 'vermin in the sky' are what I'm interested in."
With
persistence, she discovered of a type of asteroid that orbits
closer to
Earth than anyone before realized. Since then, she and other
astronomers
have found 71 asteroids in that supposedly empty part of space.
"They
prescribe doom to the Earth if one of these objects hits the
Earth,
and, of course, they're well posed to do that," Helin warns.
At first glance the idea that an asteroid would crash into the
planet
may seem far-fetched - until you consider that it's happened in
the
past. Sixty-five million years ago an asteroid seven miles in
diameter
blasted a hole 120 miles wide and 30 miles deep in the Yucatan
peninsula. It kicked up a cloud of dust and sulfur gas so dense
that it
led to the extinction of two-thirds of the species on Earth,
including
the dinosaurs. In relatively more recent times, a mere
50-thousand
years ago, a meteor crashed into the ground in Arizona. And in
1908,
just yesterday by astronomical measures, an incoming asteroid
exploded
in the air over an unpopulated area of Siberia, leveling trees
for
hundreds of square miles. If it had occurred over a city, the
result
would have been enormous loss of property and human life.
The good news is that finding near-Earth asteroids is now a
national
priority, funded by NASA and the US Air Force. And other
scientists
have studied scenarios to deflect an incoming asteroid using
nuclear
weapons to alter the orbit. Dr. Helin believes the effort and
expense
is a good investment. "This is a small insurance policy for
our
children... let's secure their future."
Related sites:
NASA - Jet Propulsion Lab <http://www.jpl.nasa.gov/>
Near Earth Asteroid Tracking <http://huey.jpl.nasa.gov/spravdo/neat.html>
-----
http://www.time.com/time/reports/v21/science/question_asteroid.html
Will a Killer Asteroid Hit the Earth?
Maybe not destroyed, but it's a safe bet that the Earth will get
really
banged up by a major piece of space rock sometime in the future.
And
that could mean disastrous consequences for the planetary
population.
Unless, of course, we clever humans catch wind of the asteroid's
approach and devise a plan to keep the threat at bay [MDASH]
possibly
returning to the script of "Deep Impact" for
inspiration.
*
http://www.time.com/time/reports/v21/science/asteroid.html
Will a Killer Asteroid Hit the Earth?
Eventually, yes. But we don't have to take it lying down. Already
astronomers are scanning the skies and preparing to defend the
planet
By LEON JAROFF
When it comes to asteroids' wreaking disaster on Earth, the real
question is not if, but when. Two hundred or so large craters and
a
geological record stretching over billions of years provide ample
evidence that, time and again, explosive impacts by asteroids or
comets
have devastated large parts of the planet, wiped out species and
threatened the very existence of terrestrial life. Astronomers
are all
too aware that more large hulks are out there, hurtling through
space,
some of them ultimately destined to collide with Earth.
As scary as this seems, disaster is not inevitable. For after
nearly 4
billion years of life on Earth, a species has evolved that can
prevent
the next catastrophic encounter if it has the will to do so. That
species is us. Why worry? After all, the most notorious impact of
them
all, the one that caused the extinction of the dinosaurs,
occurred 65
million years ago.
Really ancient history.
Yet if you want to get contemporary on a geological scale, of
course
it was only 49,000 years ago that an iron asteroid blasted out
Arizona's 34-mile-wide Meteor Crater, almost certainly killing
any
living creatures for hundreds of miles around. And as recently as
1908,
a small, rocky asteroid or chunk of a comet exploded five miles
above
the Tunguska region of Siberia, felling trees, starting fires and
killing wildlife over an area of more than 1,000 sq. mi. Had the
blast,
now estimated at tens of megatons, occurred over New York City or
London, hundreds of thousands would have died.
And what about near misses? As recently as 1996, an asteroid
about a
third of a mile wide passed within 280,000 miles of Earth < a
hairbreadth by astronomical standards. It was the largest object
ever
observed to pass that close, and had it hit, would have caused an
explosion in the 5,000-to-12,000-megaton range. What was
particularly
unnerving about this flyby is that the asteroid was discovered
only
four days before it hurtled past Earth. All the more reason for a
detection system that will discover asteroids early, plot their
paths
and predict, many years in advance, whether they will eventually
threaten
Earth.
The good news is that just such a detection system, after a slow
start,
is rapidly gearing up. Four small groups of dedicated astronomers
in
Arizona and California, totaling fewer than the number of
employees at
an average fast-food restaurant and using mostly off-the-shelf
equipment for their telescopes, have been mapping the heavens and
steadily adding to the number of known near-Earth objects.
http://www.time.com/time/reports/v21/science/asteroid2.html
Neos are asteroids or occasional comets that periodically
intersect or
come close to Earth's orbit. If a neo cuts through our orbital
path at
the same time that Earth happens by, it's curtains for a
metropolitan
area, a region or even global civilization, depending on the size
of
the interloper. In 1997 the asteroid-hunting pioneers were joined
by a
precocious upstart, a joint Air ForceM.I.T. Lincoln Laboratory
group
supported by generous Pentagon funding. Using an Air Force
satellite-spotting telescope in New Mexico and a camera equipped
with
an advanced M.I.T.-designed charge-coupled device, the totally
automated, computerized operation quickly began discovering more
asteroids and comets, large and small, than all the other groups
combined. Getting further into the spirit of the game, the Air
Force
has deployed a second asteroid-hunting scope, is lending another
to
astronomers and musing, unofficially, about launching a fleet of
microsatellites for even better asteroid detection.
What to do if an Earth-bound comet or asteroid is discovered?
Early
detection, preferably many years in advance, would enable us to
send
out exploratory spacecraft to determine the nature of the
interloper,
much like the spacecraft near's current investigation of the
asteroid
Eros. Scientists at the Los Alamos and Lawrence Livermore
National
Laboratories are already dreaming up a variety of ingenious
defenses
against an incoming asteroid. Depending on its mass and
composition,
they would use tailor-made nuclear explosions to pulverize small
asteroids or deflect larger ones. Given enough time, and under
the
proper circumstances, less drastic measures would be needed. Some
schemes call for conventional explosives alone, or anchoring a
rocket
motor or a solar sail on an asteroid to alter its orbit enough to
allow it to safely bypass Earth.
At the beginning of 2000, only about half the estimated
500-to-1,000
near-Earth asteroids six-tenths of a mile across or larger<big
enough
to cause a global catastrophe<had been detected. One of the
unknowns
could even now be on a collision course with Earth. The sudden
appearance of long-period comets, usually larger and with better
than
twice the impact velocity of asteroids, presents an even greater
menace. Such objects (comet Hale-Bopp was one) are usually not
spotted
until they begin to flare somewhere out near the orbit of Jupiter
or
closer, only a few to 18 months before they pass Earth's orbit.
That
doesn't leave much time for defensive measures. Then, too, only a
tiny
fraction of the more numerous and smaller neos, some of them
potential
city killers and tsunami producers, are yet known.
Someday in the foreseeable future, the first thing that strollers
out
for an evening walk might see would be a sudden glow on the
horizon.
Then, in short order, they would feel the ground shake, hear a
thunderous roar and be incinerated by an onrushing blast of
superheated
air. All the more reason to identify and track every single
near-Earth
object and prevent a nasty surprise.
================
(3) NEAR SHOEMAKER SCIENCE UPDATE
From Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
Near Shoemaker Science Update
March 31, 2000
http://near.jhuapl.edu/news/sci_updates/00mar31.html
As NEAR Shoemaker continues orbital mapping from its 200 km
orbit, more
and more details are emerging about the geologic features on
Eros's
surface. Three examples of what we are seeing were released as
images
of the day for March 17, March 20 and March 21. In all cases we
are
looking at the north polar region of Eros, but under different
viewing
and illumination conditions. By comparing sets of images as
these,
looking for features that are viewed in multiple images, we can
infer
whether portions of a feature look dark because of true
brightness or
reflectivity variations, as opposed to looking dark because of
oblique
illumination and/or viewing. In this way we sort out the detailed
shapes of the features and any reflectivity variations that may
be
present, so we can classify the features and map their
distributions
across the asteroid. Mapping the features is a challenging task,
especially on an irregularly shaped object like Eros, but it is
critical to piecing together the story of how Eros came to be
what it
is. It is by mapping that we can study the spatial relationships
- the
degrees to which linear features line up and the ways in which
features
meet and/or cross one another - which provide clues to the nature
of
the underlying geologic processes. We shall return to the topic
of
mapping later.
In the image of the day for March 17 we can see three boulders at
the
top of the image - these are 80 m boulders sitting on the eastern
rim
of the large depression we have been calling the 'saddle'. We
know
these are boulders, protruding above the surface, because of
where the
shadows fall (toward the bottom of the image, whereas for craters
the
shadowed side is toward the top). At the lower left of this
image,
where the Empire State Building is outlined for scale, is the 5.5
km
crater we have been calling the 'paw' (the reason for that name
is not
evident in these images). The 'paw' is the same crater with the
prominent rim that appears in the top of the March 20 image
(toward the left) and that I
wrote about on February 8 and February 15. Now that we are
oriented, we
can examine the large crater on the far left of the March 17
image
which has light and dark areas within its walls. This same large
crater
appears in all three images. It is in the center-left, below
the paw, in the March 20 image, and it is on the horizon, at the
lower
left, in the March 21 image. We note especially that the pattern
of light and dark areas is reproduced consistently in the three
images.
This is convincing evidence that there are true brightness
variations
in the materials lining the walls of this crater. We have seen
consistently that the "bright spots" mentioned
previously (see, for
example, the February 15 update) are areas of higher reflectivity
in
the walls of craters.
Another important feature that appears in all three images is a
long
ridge that extends much of the way around the asteroid at its
waist.
Again, we know this feature is a ridge, standing above the
surface,
because of the side that the shadow falls on. In the March 17
image, the portion of the ridge that we can see begins at the
left edge
of the image immediately above the crater we have just discussed,
and
it points toward the boulders in the saddle. We can then find the
ridge
in the March 21 image, left side, and in the March 20 image,
cutting
diagonally across the lower left corner. This same corner is
where
an unusually smooth area, that may be relatively young, can be
seen.
Both this smooth area and the ridge have important stories to
tell
about the geology of Eros, but our studies of these features have
barely begun.
Our focus on lighting conditions and their importance for
understanding
the images may seem surprising, but the lighting geometry is much
more
important on airless bodies like Eros than it is on Earth. Our
atmosphere scatters light and creates diffuse lighting (where
light
comes from many directions at once). Diffuse lighting is
especially
prevalent indoors, as most of us make an effort to achieve that
condition by putting shades and diffusers on lamps. With diffuse
lighting, the effects of shadows and oblique illumination are
reduced,
but there is very little diffuse light on the surface of Eros.
Most of
us who live on Earth have no experience of such lighting - the
only
people who have actually seen it in nature are the lucky few who
walked on the Moon.
Andrew Cheng
NEAR Project Scientist
==============
(4) SPACE DUST MEETING IN THE UK
From Peter Bond < 100604.1111@compuserve.com
>
ROYAL ASTRONOMICAL SOCIETY
PRESS INFORMATION NOTE
Date: 4 April 2000
Ref. PN 00/06
Issued by:
Peter Bond,
RAS Press Officer (Space Science).
10 Harrier Close,
Cranleigh,
Surrey, GU6 7BS,
United Kingdom.
Phone: +44 (0)1483-268672
Fax: +44 (0)1483-274047
E-mail: 100604.1111@compuserve.com
FOR MORE INFORMATION ON THE COLLOQUIUM CONTACT:
Dr. John Zarnecki,
Unit for Space Sciences,
Physics Laboratory,
University of Kent,
Canterbury
KENT
CT2 7NR
United Kingdom
Tel: +44 (0)1227-823237 or (0)1227-823788
Fax: +44 (0)1227-827558
E-mail: j.c.zarnecki@ukc.ac.uk
FOR MEDIA ENQUIRIES CONTACT:
Posie Bogan or Jane Hardy,
Communications and Development Office,
The Registry,
University of Kent,
Canterbury,
KENT
CT2 7NZ
Tel: 01227-823581 or 823100
Fax: 01227-764464
E-mail: p.h.bogan@ukc.ac.uk
OR j.e.hardy@ukc.ac.uk
Abstracts and further information about the meeting are on the
Web at:
http://www.ukc.ac.uk/physical-sciences/space/
UNIVERSITY OF KENT IS HOST FOR AN INTERNATIONAL COLLOQUIUM ON
DUST IN
THE SOLAR SYSTEM AND OTHER PLANETARY SYSTEMS.
Astronomers from all over the world will be converging on the
University of Kent next week (10-14 April 2000) to attend a major
international colloquium on interplanetary dust.
The colloquium, which is co-sponsored by the International
Astronomical
Union (IAU), the Committee On Space Research (COSPAR), the Royal
Astronomical Society, the University of Kent and Unispace Kent,
is the
seventh in a series of meetings which began in Hawaii in 1967.
Over the last five years, studies of interplanetary dust have
been
changed dramatically by in-situ space experiments on the Galileo
and
Ulysses spacecraft, remote sensing from the Infrared Space
Observatory
(ISO) and ground-based observations of Comet Hale-Bopp. A further
flood
of new data will soon be available from the Cassini and Stardust
spacecraft, from Earth-orbiting satellite observations and from
studies
of the annual Leonid meteor stream.
At the same time, our knowledge of other potential dust sources
has
made great strides as new techniques and instrumentation become
available. While the NEAR spacecraft orbits near-Earth asteroid
Eros,
an increased awareness of the danger to our planet from such
bodies has
led to new observational programmes which are improving
scientists'
estimates of the population of our cosmic neighbours. Other
potential
sources of space dust linger in the outer reaches of the Solar
System,
where astronomers are beginning to uncover millions of icy worlds
within the Edgeworth-Kuiper Belt.
Finally, with dust disks and extrasolar planets now being
discovered
almost monthly, astronomers are able, for the first time, to
compare
our Solar System with other far away star systems. Such
comparisons
enable scientists to gain new insights into the processes which
took
place in the dust disk around our Sun some 5 billion years ago.
THE PROGRAMME.
Although space dust is the focus of the meeting, there will not
be any
time for dust to settle once the colloquium gets under way. The
packed
programme comprises about 80 scientific papers, as well as dozens
of
poster presentations, spread over 17 sessions. All aspects of the
astronomical study of interplanetary dust are covered. The
sessions
are, in order of presentation:
Monday 10 April: Meteors. Meteoroid Streams. The Zodiacal Light.
Zodiacal Dust.
Tuesday 11 April: The Galileo, Ulysses, Cassini, and Stardust
Space
Missions.
Wednesday 12 April: Dust in Other Solar Systems. The
Edgeworth-Kuiper
Belt.
Thursday 13 April: Dust Sources (Comets and Asteroids). Cometary
Dust.
The Rosetta Mission. Grain Aggregation and Optical Studies
Friday 14 April: Applications and Links (Laboratory Experiments,
Models
and Their Implications). Dust in Earth Orbit. Origins…(Space
Dust and
the Earth).
HIGHLIGHTS.
Some of the highlights of the meeting are briefly summarised
below:
THE LEONID METEOR SHOWER. Monday 10 April.
A number of papers describe results from the 1998 and 1999
appearances
of the Leonid meteors. They include:
· LEONID IMPACTS ON THE MOON IN 1999. A report on results from
the
impact flashes of Leonid meteoroids on the night side of the Moon
during the 1999 return of the shower. Presented by Luis Bellot
Rubio
(Instituto de Astrofisica de Canarias in Spain, and the
International
Meteor Organisation).
· THE 1999 LEONID MULTI-INSTRUMENT AIRCRAFT CAMPAIGN. A report
on the
November 1999 airborne campaign, sponsored by NASA and USAF, to
fly
over the Mediterranean and view the Leonid meteor storm from
above the
clouds. Presented by Peter Jenniskens (SETI Institute, NASA
Ames
Research Centre).
SPECIAL SESSION ON THE NASA STARDUST MISSION. Tuesday 11 April.
The 4th NASA Discovery Mission, Stardust, was launched on 7
February,
1999. The spacecraft's dust collector has now been deployed and
will
collect samples of interplanetary material on the journey to
Comet
Wild-2. On arrival at the comet, samples from its coma will be
captured
for return to Earth in January 2006 by a direct re-entry capsule.
Among
those giving presentations are Principal Investigator Donald
Brownlee
(University of Washington, Seattle, USA), P. Tsou and Martha
Hanner
(Jet Propulsion Laboratory, Pasadena, USA).
DETECTION OF ELECTRICALLY CHARGED DUST PARTICLES WITH THE CASSINI
DUST
EXPERIMENT (CDA). Tuesday 11 April.
CDA will spend five years collecting data on interplanetary dust
during
its odyssey to the planet Saturn. Presentations on how the
CDA
instrument works and the first results from the experiment will
be
presented by Siegfried Auer (Basye, Virginia, USA) and Ralf Srama
(Max-Planck-Institut für Kernphysik, Germany).
DUST TELESCOPES: A NEW TOOL FOR DUST RESEARCH. Tuesday 11 April.
A state-of-the-art dust telescope, consisting of an array of
parallel
mounted dust analysers, is under development. A first application
of
such an instrument has been proposed to ESA as the Galactic DUNE
mission for the analysis of interstellar grains in Earth orbit.
Presented by Eberhard Grün (Max-Planck-Institut für Kernphysik,
Germany).
DUST EN ROUTE TO THE GIANT PLANETS AND THE GALILEAN SATELLITES.
Tuesday 11
April.
The Galileo and Ulysses spacecraft carry identical highly
sensitive
impact ionisation dust detectors on board. Both instruments have
recorded impacts of micrometeoroids in interplanetary space at
heliocentric distances 0.7 to 5.4 AU, and within the Jovian
system.
Close flybys of the Galilean satellites have revealed that these
moons
are surrounded by thin, impact-generated, dust clouds. Another
tenuous
ring of 'big' grains has been detected in the region between the
Galilean satellites. Presented by Harald Krüger
(Max-Planck-Institut
für Kernphysik, Germany).
THE ROSETTA MISSION TO COMET WIRTANEN. Thursday 13 April.
An overview of the European Space Agency's historic 11-year-long
mission to put a spacecraft into orbit around a comet nucleus and
release a lander onto its surface. On the way to the comet,
Rosetta
will fly past two unusual main belt asteroids. Launch is
scheduled for
January 2003. Presented by Project Scientist Gerhard Schwehm
(European
Space Agency).
DUST CHARACTERISATION IN THE NEAR EARTH ENVIRONMENT: STATUS AND
NEW
OPPORTUNITIES. Friday 14 April.
A review of future opportunities to detect meteoroids or space
debris
with the ESA-Kent real time detector, DEBIE. These include launch
this
year on the British STRV-1c satellite into a geostationary orbit
above
the equator, launch into polar orbit on the PROBA satellite, and
deployment on the International Space Station. Presented by Neil
McBride (University of Kent).
LARGE PARTICLE DETECTION ON MIR SOLAR ARRAYS. (Poster
presentation.)
Joint co-operative missions between Shuttle-Mir have provided
opportunities to acquire close-up photographic imagery of Mir's
solar
arrays. These data may be used to study the effects of prolonged
exposure to space environments at an altitude 330-360 km and
51.62°
inclination, including impact from dust. Imagery has revealed in
excess
of 50 large surface features on seven of Mir's twelve arrays,
suspected
of being caused by meteoroid or orbital debris strike. Presented
by
Mark Herbert (University of Kent)
INTERSTELLAR DUST INFLOW TO THE SOLAR SYSTEM MAPPED BY AMOR.
Friday 14
April.
New data from the Advanced Meteor Orbit Radar (AMOR) facility
support
the idea that some of the meteoroids entering our atmosphere
originate
outside the Solar System in interstellar space. Presented by Jack
Baggaley (University of Canterbury, New Zealand).
BACKGROUND INFORMATION.
The University of Kent has been a focus for studies of the space
environment for many years. Apart from analysis of Apollo lunar
samples
and involvement in the Giotto mission to Comets Halley and
Grigg-Skjellerup, the University's Unit for Space Sciences has
specialised in research into interplanetary dust. Among the key
facilities in the Unit is a microparticle accelerator, in which
dust
particles can travel at up 200 km/s, and a light gas gun which
fires
small projectiles at speeds up to 7.5 km/s. Experimental data
from
these facilities is used to improve understanding of
hypervelocity
impacts in space, and risks to spacecraft from space debris and
meteoroids.
The University is also currently involved in a number of space
missions, including Ulysses, Galileo, Stardust, Rosetta, Mars
Express
and Cassini (with leadership of the Surface Science Package on
the
Huygens probe which is scheduled to land on the surface of
Saturn's
moon Titan in 2004). It is also developing a new class of orbital
space
detector for micrometeoroids, known as Debie.
=============================
* LETTERS TO THE MODERATOR *
=============================
(5) WHERE IS THE MARTIAN MAGNETIC FIELD FOR
MARTIAN MAGNETOTACTIC BACTERIA?
From Gerrit Verschuur < GVERSCHR@LATTE.MEMPHIS.EDU
>
Dear Benny,
Regarding the contribution to CCNet under the heading MARTIAN
METEORITE
DEBATE ALIVE AND KICKING, Everett Gibson wrote:
"Among the indigenous Martian biogenic signatures are: (a)
magnetites
which are distinctly from magnetotactic bacteria and are clearly
within
carbonates which are of Martian origin ..."
Terrestrial magnetotactic bacteria evolved their magnetic
sensitivity
for a purpose, which was to allow them to follow geomagnetic
field
lines to reach sediments, and hence nutrients. While it is
tantalizing
to accept that such bacteria existed on Mars, one wonders where
the
Martian magnetic field is to which such organisms out there would
have
adapted. Are we to interpret the Martian meteorite data even
further
this forcing us to conclude that Mars once had a magnetic field?
I am
even more skeptical now.
Gerrit Verschuur
=================
(6) NEOS & THE IMPACT HAZARD VIEWED FROM VIENNA
From Giesinger Norbert < norbert.giesinger@siemens.at
>
Dear Dr. Peiser,
Greetings from Vienna.
I saw you on Friday, March 31, in the NEO discussion on Spiegel
TV/
VOX. I found the moderatress quite good, however, there was not
enough
time for discussion. I was astonished to hear your fluent and
very good
articulated German! Probably I should use my mother language and
not
write in poor English to you.
Some weeks ago there was a discussion of a large group concerning
catastrophes on a German TV station (I think it was Hessen TV)
where
German astronaut Walter gave some very competent statements
concerning
the long term danger from NEOs and the idea to built a save haven
i.e.
an extraterrestrial habitat. From a number of discussion
participants,
he was ridiculed (in my eyes treated as an idiot).
Here in Vienna, a positive event in connection with
impacts/meteorites
took place 4 weeks ago. In the Vienna Museum of Natural History,
the
large exhibition room for the earths Middle Ages
(Trias/Jura/Kreide)
was reopened after it was closed for 21(!) years. There is a nice
video
display concerning the K/T impact.
A real stone layering showing the ~5cm high K/T boundary is the
final
part of the exhibition on the door to the Kanäozoic room in the
mueseum. The stone layering including the K/T boundary was taken
from
Gams near Hieflau in Upper Styria. In this area ("Gamser
Becken"), 230
million years are open on the surface. Dr. Kollmann from the
Natural
History Museum made his PhD work there back in 1964. Now they
have a
geotrail in the area of the village and the ca. 700 inhabitants
are
building a geological/paleontological museum. I hope to make a
trip to
Gams in the coming weeks to see myself.
The large meteorite expostion (a separate large room) in the
Vienna
Museum of Natural History was also renovated a bit. Whenever you
come
to Vienna, you should see it, there are also some large iron
meteorites
to touch which is much fun for kids.
Sincerely yours,
Norbert Giesinger
==============
(7) AND FINALLY: INFORMATIZATION IS MAKING CIVILISATION FAIRER
H. Cleveland: The informatization of development. CURRENT
SCIENCE,
1999, Vol.77, No.11, pp.1426-1430
UNIVERSITY OF MINNESOTA,WORLD ACAD ART & SCI,HUBERT H
HUMPHREY CTR
161,301 19TH AVE S,MINNEAPOLIS,MN,55455
The new millennium opens the door to fundamental changes to make
civilization fairer to all peoples. Ten concurrent revolutions
stern
from the huge transformation in our global information
environment. The
widespread of information - abundant, transportable, leaky,
shareable -
bodes well for a fairer world, undermining the structures of
hierarchy
and discrimination that have privileged those 'in the know'. But
the
disadvantaged will need to work hard at learning how to use the
powers
inherent in this more accessible resource. Copyright 2000,
Institute
for Scientific Information Inc.
----------------------------------------
THE CAMBRIDGE-CONFERENCE NETWORK (CCNet)
----------------------------------------
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subscribe/unsubscribe,
please contact the moderator Benny J Peiser < b.j.peiser@livjm.ac.uk
>.
Information circulated on this network is for scholarly and
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