PLEASE NOTE:
*
CAMBRIDGE-CONFERENCE DIGEST, 1 April 1998
-----------------------------------------
(1) A MESSAGE FROM THE GENERAL SECRETARY OF THE UNITED NATIONS
Coughy Anan@united.nations.hq
(2) PANDORA'S BOX IS OPEN - YOU CAN'T CRAM IT ALL BACK AND SHUT
THE LID
Duncan Steel <dis@a011.aone.net.au>
(3) A CASE STUDY OF THE ASTEROID 1997 XF11 AFFAIR
Clark Chapman <cchapman@boulder.swri.edu>
(4) UK ASTRONOMERS FIND FAINT OBJECTS BEYOND PLUTO
Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
=========================
(1) A MESSAGE FROM THE GENERAL SECRETARY OF THE UNITED NATIONS
From: Coughy Anan@united.nations.hq
Dear NEO researchers
I am pleased to inform you that due to the recent events
surrounding
asteroid 1997 XF11 the general assembly of the United Nations has
today
decided in an unananimous vote to provide $ 500m in funds for
setting up
a global system of NEO detection and R&D in NEO deflection
for the next
10 years. Brothers and sisters, we are all convinced that this
money
(most of which will come from the outstanding US subs, anyhow) is
well
spent and will help to make the world a saver place. However,
before
handing out the dosh, the nations of the world would like to call
on
you to overcome you own discord and start joining forces.
In the hope that NEO researchers around the world will be just as
united and unanimous as we have always been, I remain
yours faithfully
Coughy Anan
UN Hq, New York, 1 April 1998
=========================
(2) PANDORA'S BOX IS OPEN - YOU CAN'T CRAM IT ALL BACK AND SHUT
THE LID
From: Duncan Steel <dis@a011.aone.net.au>
Dear Benny,
I note Rick Binzel's posting through the CC Digest, and also
press reports
of the apparent agreement for coordination between various
professionals
IN THE USA regarding possible press announcements (or indeed any
mention
anywhere) about future situations where 'close' approaches to the
Earth by
NEOs are predicted, and impacts cannot be ruled on on the basis
of data in hand.
Unfortunately these attempts to control the dissemination of
information
which is potentially (well, actually) alarming to the general
populace are
doomed to failure. Firstly, not all the professionals in
NEO research work
in the USA, and so are controllable in this way (either through
direct
pressure, funding considerations, and so on), and to keep this
secret from
the WORLD's media through that avenue would require a black-out
on the part
of the professionals world-wide. Secondly, there are
amateurs both in the
USA and elsewhere who are now capable of making the required
calculations to
predict near-misses. Many already had that capability
(i.e., ephemeris
programs which are accurate enough for a few decades), but the
announcement
through the CC Digest and elsewhere from Andrea Milani and
colleagues of the
free availability through the WWW of the necessary software makes
it likely
that the numbers of amateurs (and professionals) able to make the
calculations will now be growing significantly. If anyone
thinks that it
will be possible to keep all those people quiet, it is likely
that they also
believe that Elvis Presley killed JFK (or vice-versa).
Not only is the software available to amateurs, note that much of
the data
(NEO astrometry) derives from their efforts too. Is there
to be an attempt
to control access to NEO astrometry until after the appointed
authorities
have decided to sound the all-clear?
Thus I'd like to make a prediction, as follows. If this
attempt to control
the availability to the media of stories like that of 1997 XF11
goes ahead,
through the implementation of whatever agreements between US
professionals,
then what will happen is that an amateur somewhere will routinely
run the
software on some very recent discovery, find a close approach in
some
decades' time, tell his local friendly journalist, and then the
story will
be picked up by the wires and the presses and phones will be
running hot.
When it is realized that the news got out through, say, some
amateur
astronomer living in Lapland, and that the data were available to
various US
government instrumentalities (NASA, CfA, etc.), and that the
information had
been deliberately suppressed, there will be a furore totally
dwarfing that
over 1997 XF11. With good cause. To say the least
this will diminish the
estimation of NASA (and others) in the eyes of the American
public. For
once the conspiracy theorists will have grounds for their
beliefs: this
would be a conspiracy to keep people in the dark. It will
fail.
I write the above not to 'blame' anyone for recent events, or to
support or
contradict the views of others about the desirability or
otherwise of scares
such as that represented by 1997 XF11. I am just saying
that my belief is
that any such attempt by American professional astronomers to
control the
outflow of information on this topic is virtually certain to
fail, given the
present availability of NEO astrometry to all and sundry
(and if anyone tries to change that availability then the media
will be onto
it in a flash).
Put simply, Pandora's Box is open. The best that can be done is
to try
to direct the outflow from the box so as to achieve the least
harm/most
good. You can't cram it all back in and shut the lid.
Regards,
Duncan Steel
======================
(3) A CASE STUDY OF THE ASTEROID 1997 XF11 AFFAIR
From: Clark Chapman <cchapman@boulder.swri.edu>
Benny,
I have now written some material as a preface to my "Case
Study" at
www.boulder.swri.edu/clark/ncar.html
Excluding the first paragraph of the Preface (which deals with
the document itself), the remaining 7 or 8 paragraphs constitute
a "one-page-long" summary of my perspectives.
Clark
Preface. The following Case Study is a DRAFT. Since the last
revision,
many colleagues have offered additional information and
corrections (which, I'm sorry to say, I have not yet had time to
incorporate), chiefly concerning the complicated circumstances
surrounding the 1997 XF11 asteroid impact scare of mid-March. The
detailed technical analysis of what several research groups did,
and how they communicated their results and opinions with each
other and with the media, is still not fully understood by me,
nor
by anyone else. It will, however, be important to document it so
that better procedures can be developed that take account of the
"realities" that develop in circumstances like those in
mid-March.
Certainly, with the rates of discovering NEO's increasing
rapidly,
there will be future cases that the NEO scientific community will
have to face. Many are bound to have differences from the case of
1997 XF11, but the XF11 case typified many of the issues that I
expect to happen again.
My simplified view of the XF11 affair is this: There are roughly
2000 Earth-approaching asteroids that approach or exceed the
"1
mile wide" size that David Morrison and I have established
as
possibly civilization-threatening. Less than 10% of these have
been discovered. The job for NEO astronomers is to discover as
many of the remaining ones (NASA's stated goal, not yet
implemented, is 90% of them in the next decade), and to determine
their orbits. Almost certainly, as each one is discovered, it
will
be demonstrated within days (occasionally as long as a few years)
to NOT be on a collision course with Earth. As we go through this
process of certifying that asteroids will NOT strike the Earth,
we
will gradually reduce the probability of impact in the succeeding
30 years from the current 1 chance in 10,000 to 1 chance in
100,000 (from the remaining 10%).
As of March 11th, observations of the position of 1997 XF11 had
been reported to the IAU Minor Planet Center over a three-month
period. The good news is that those data, and those data alone,
were sufficient to demonstrate the 1997 XF11 would NOT hit the
Earth during its approach in 2028 or at any other time in the
foreseeable future (more specifically, that the chances of XF11
impacting the Earth could be shown to be MUCH less than the
background probability -- 1 chance in 10,000 -- of an unknown
asteroid hitting us before 2028).
But, instead of adding 1997 XF11 to the slowly growing list of
asteroids certified as not going to hit the Earth, the director
of
the Minor Planet Center, Brian Marsden, instead made an
announcement to the world (via the IAU Circulars he edits and an
associated press statement) that the asteroid was "virtually
certain" to pass within 80% of the distance to the Moon and
stood
a "small...not out of the question" possibility of
hitting the
Earth. (It is not yet known, to me, whether Marsden's
calculations
were faulty or rather that he misinterpreted them and/or used
ill-chosen words to convey his results.)
Because Marsden has a policy of holding onto the data he receives
from the world's astronomers, and of doing his own evaluation of
the data before making them available to other astronomers,
nobody
else had the practical capability of making independent
calculations. Moreover, Marsden didn't bother to check his
results
with colleagues at other institutions before making his faulty
announcement to the world. Within hours, Marsden was persuaded to
release the data, and within hours of that, several other
astronomers had correctly calculated that the probability of
Earth
impact was essentially zero -- certainly much less than the
probability of impact from the as-yet-undiscovered asteroids.
Already during the evening of March 11th, several astronomers
requested that Marsden issue a public correction, and tell the
anxious world that new calculations by other astronomers showed
that the asteroid would not hit. He explicitly refused to do so.
Even by noon the following day, Marsden was still telling
reporters that the asteroid could hit. If no prediscovery
observations were ever located and no subsequent observations of
XF11 were ever made, a proper analysis of the Dec. 1997 - Mar.
1998 data -- done by several other astronomers within hours of
being provided the data by Marsden -- clearly places 1997 XF11 in
the "not dangerous" category.
Marsden finally, late on the 12th, changed his prediction to
"no
impact", using as an excuse the arrival, and inclusion in
his
calculations, of prediscovery data from 1990. It is essential to
realize, however, that this was "icing on the cake."
Every other
expert on NEO's had already concluded that 1997 XF11 was in the
"safe" category long before the 1990 data became
available.
In the future, it will be necessary for NEO scientists to do what
scientists have traditionally done for centuries, which is to
have
important results peer-reviewed before they make rash
announcements to the public. To facilitate this, all data from
the
international astronomical community should be disseminated as
rapidly as is technically possible, and procedures should be
implemented to cross-check and peer-review announcements of
potentially hazardous close approaches before such conclusions
are
published (i.e. made public). This should be done rapidly. I
hasten to add that such a procedure is NOT "secretive"
-- it is
the normal way that scientists report results and ensures that
the
public can have some degree of confidence that the reported
results are reliable.
I hope to incorporate further corrections in my Case Study within
about a week, and I continue to solicit comments, suggestions,
corrections, etc.
Clark R. Chapman, 31 March 1998.
=========================
(4) UK ASTRONOMERS FIND FAINT OBJECTS BEYOND PLUTO
From: Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
Royal Astronomical Society Press Notices
Date: 27 March 1998
Ref. PN 98/07 (NAM 4)
Issued by:
Dr Jacqueline Mitton
RAS Public Relations Officer
Phone: Cambridge ((0)1223) 564914
FAX: Cambridge ((0)1223) 572892
E-mail: jmitton@ast.cam.ac.uk
UK ASTRONOMERS FIND FAINT OBJECTS BEYOND PLUTO
UK astronomers have discovered two of the faintest objects ever
seen
orbiting our Sun. One is estimated to be 150 km (90 miles) across
and the
other 110 km (70 miles). Both are about 45 times farther from the
Sun than
Earth (4,200 million miles or 6,750 million km), and more remote
than the
planet Pluto, which is currently 30 times farther from the Sun
than Earth.
The objects belong to the so-called Kuiper Belt in the region of
space
beyond the planet Neptune. Since 1992, 61 Kuiper Belt objects
('KBOs') have
been discovered, including 7 found by the same UK team. Most are
over 200 km
across.
But rather like the curious incident of the dog that famously did
nothing in
the night-time [in the Memoirs of Sherlock Holmes] it is the fact
that the
team DID NOT find more objects that may prove to be a highly
significant
clue as astronomers probe the mysteries of these outer reaches of
the solar
system. Based on present ideas about how Kuiper Belt objects
formed,
astronomers expected to be finding these faint objects at even
greater
distances. Since they did not, those ideas may need to be
revised. It may be
that the average size of the KBOs is smaller the farther away
they are, so
the most distant ones were too faint even for this survey. Or it
might be
that the objects actually discovered mark the outer edge of the
Kuiper Belt.
These latest results will be presented at the National Astronomy
Meeting at
the University of St Andrews on Tuesday 31st March by Dr Alan
Fitzsimmons of
Queen's University Belfast on behalf the team, which also
includes Miss Edel
Fletcher (Queen's University of Belfast), Dr Mike Irwin (Royal
Greenwich
Observatory) and Professor Iwan Williams (Queen Mary &
Westfield College
London).
Hardly any previous searches have been targeted on objects as
faint and as
small as those the UK team were looking for when they made the
observations
in November 1997. They used the 2.5-metre Isaac Newton Telescope
on La Palma
to image the sky for 7 nights, searching a total area slightly
smaller than
that covered by the full Moon. On the telescope they had a new,
sensitive,
wide-field camera built by the Royal Greenwich Observatory. The
new camera
can see five times as much sky as the one previously used.
During each night they stared continuously at different patches
of sky for
up to four hours at a time. In each patch of sky several thousand
distant
stars and galaxies could be seen. However even these images were
not
sensitive enough to record the solar system objects the team were
seeking.
So they combined the images by computer in a way that eliminated
all stars,
galaxies and nearby asteroids and revealed only faint
solar-system objects
at large distances from the Sun.
Two new objects were discovered. One is roughly 150 km in
diameter, while
the other is only 110 km across. Both appear to be around 45
times further
from the Sun than the Earth. At this distance, the smallest
object was forty
million times fainter than the faintest stars that can be seen by
eye on a
dark night. They are so faint that it is not worth taking up all
the
telescope time needed to track them in the future, and it is very
unlikely
they will ever be seen again.
Contact
Dr Alan Fitzsimmons
Dept. of Pure & Applied Physics
Queen's University of Belfast
Belfast BT7 1NN
Northern Ireland
Tel: 01232-273124
Fax: 01232-438918
e-mail: a.fitzsimmons@qub.ac.uk
http://star.pst.qub.ac.uk/~af/af.html
Press room at the National Astronomy Meeting, University of St
Andrews
(8.30 - 18.00 Tue 31 March to Thur 2
April; 9.00 - 12.00 Fri 3 April):
Phone: 01334-462168 and 01334-462169
Fax: 01334-463130
--------------------------------
THE CAMBRIDGE-CONFERENCE NETWORK
--------------------------------
The Cambridge-Conference List is a scholarly electronic network
moderated by Benny J Peiser at Liverpool John Moores University,
United Kingdom. It is the aim of this network to disseminate
information and research findings related to i) geological and
historical neo-catastrophism, ii) NEO research and the hazards to
civilisation due to comets, asteroids and meteor streams, and
iii) the
development of a planetary civilisation capable of protecting
itself
against cosmic disasters. To subscribe, please contact Benny J
Peiser
<b.j.peiser@livjm.ac.uk>.
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.