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(meteorobs) Fw: CC DEBATE, 2 April 1998 via Bigrock
----------
> From: Benny J Peiser <B.J.PEISER@livjm.acdot uk>
> To: cambridge-conference@livjm.acdot uk
> Subject: CC DEBATE, 2 April 1998
> Date: Thursday, April 02, 1998 10:47 AM
>
> CAMBRIDGE-CONFERENCE DEBATE, 2 April 1998
> ----------------------------------------
>
> (1) DON'T COUNT YOUR CHICKENS BEFORE THEY HATCH, PARTICULARLY NOT ON
> APRIL 1st
> Benny J Peiser <b.j.peiser@livjm.acdot uk>
>
> (2) JUST WHEN YOU THOUGHT 1997 XF11 HAD GONE AWAY
> Brian G. Marsden <bmarsden@cfa.harvarddot edu>
>
> (3) ON ADOPTING A NEO HAZARD INDEX
> Gerrit Verschuur <GVERSCHR@MSUVX1.MEMPHISdot edu>
>
> (4) AXIOM ON PUBLIC ANNOUNCEMENTS SHOULD BE APPLIED INTERNATIONALLY
> Richard Binzel <rpb@astron.mitdot edu>
>
> (5) A COMMENT ON DUNCAN STEEL'S "PANDORA'S BOX"
> Clark Chapman <cchapman@boulder.swridot edu>
>
> =====================
> (1) DON'T COUNT YOUR CHICKENS BEFORE THEY HATCH, PARTICULARLY NOT ON
> APRIL 1st
>
> From: Benny J Peiser <b.j.peiser@livjm.acdot uk>
>
> Can you imagine how much I shrieked with laughter when an American
> colleague was so kind to tell me that one of our honourable members
> almost swallowed yesterday's message by Coffee Anan?
>
> > Tom, Bob, Jim, and Dan:
> >
> > I received a message via the CC Digest saying the UN is going to spend
> > $500,000,000 to build a "global system of NEO detection and R&D in NEO
> > deflection for the next 10 years." This is, however, released on 1
April
> > 1998, so its authenticity is suspect. Do you have any independent
> > verification that such a committment has been made?
>
> While this reaction certainly made my day, I was even more pleased when
> I was informed by a reliable source that yesterday's UN "committment"
> was - guess what - actually forwarded to the Secretary General, Kofi
> Anan, by one of his acquaintances. And that's no joke!
>
> The rest of today's debate on the CCNet is, I'm afraid to say, of a
> more serious nature. It is the start of a critical re-assessment of the
> events surrounding asteroid 1997 XF11 and the main lessons the
> astronomical community in general and NEO researchers in particular
> have to learn for similar events in the future. With more than
> 1,000,000 amateur astronomers world-wide and numbers growing
> continuously, the discovery of new asteroids and comets on an orbit
> with close approch to Earth is inevitable and just a question of time.
> Thus this discussion is of great concern to all who are either directly
> involved or simply interested in NEO research and, more importantly,
> the fundamental implications of the NEO threat on human, social and
> scientific conduct in the free world.
>
> Benny J Peiser
>
> ==================
> (2) JUST WHEN YOU THOUGHT 1997 XF11 HAD GONE AWAY
>
> From: Brian G. Marsden <bmarsden@cfa.harvarddot edu>
>
> My article in the March 29 Boston Sunday Globe, as well as the extended
> version that appeared in the March 30 CC DIGEST, was obviously a
> popularized account of my view of the 1997 XF11 affair. It had been my
> intention, at some stage, to address the more complex issues in more
> detail, and Clark Chapman's "case study", which appeared in the
> otherwise delightful April 1 issue of the CC DIGEST, provides an
> appropriate impetus. Since, in his capacity as new chairman of the IAU
> Working Group on Near-Earth Objects, Dave Morrison was gratuitous
> enough to send Chapman's item and my extended Globe article to much of
> the IAU leadership, I shall trust that my response here receives the
> same treatment. Note that I shall basically refer to the particular
> version of Chapman's remarks that actually appears in the CC DIGEST,
> although DIGEST readers will be aware of the reference there to
> Chapman's 2500-line Web manifesto, parts of which are being construed
> by many as libelous, and on which I might touch. If, as Chapman notes
> in his introductory paragraph to the DIGEST (but not the distributed)
> version, "the detailed technical analysis ... is still not fully
> understood" by him, one rather wonders how he can so confidently
> describe what happened.
>
> Is it more important to make probability estimates of impacts on the
> basis of limited observational data or to try and secure additional
> data? This is an interesting question, and your answer may well depend
> on whether you are a theoretician or an observer. Chapman takes the
> view that only the former is important, the additional 1990 data being
> just "icing on the cake". (But why stop there? If the 1990 data were
> mere icing, why not also the Shelus data from 1998 March 3 and 4 that
> he so chided me for withholding?). The fact is that 1997 XF11 is one of
> the largest objects that CAN come very close to the earth, and that it
> WOULD come particularly close in 2028 was already evident from the data
> in the February MPCs, and even from those in the January MPCs. The
> worrisome thing is that nobody became interested in the object earlier:
> Shelus' observations were the first ones in a whole month, and those
> interested in such things seem not to have made any effort to obtain
> physical data that could establish an albedo and size. It should not in
> fact have been necessary for there to be an urgent scramble on March 12
> to search for old images. As soon as objects are added to the list of
> PHAs (as 1997 XF11 was in December), they should (if reasonably bright)
> surely become prime candidates for physical studies; and as soon as
> there is a halfway decent orbit determination (January, certainly
> February, for XF11), mechanisms should be established for searching for
> old images. Such activities must be considered part of the NEO
> enterprise, and they (and follow-up astrometry generally) are every bit
> as deserving of funding as are searches for new objects. After all,
> examination of old plates, and CCD recovery attempts for faint objects,
> were the principal modi operandi of the late and very much lamented NEO
> program at Siding Spring.
>
> So, considering that we were dealing with a computation, from available
> data, that even amateur astronomers could do (as Duncan Steel also
> aptly pointed out in the April 1 CC DIGEST), there was every reason to
> issue IAUC 6837, with a call for further observations, even physical
> observations. The possibility of finding past observations was handled
> in the accompanying "press information sheet" (or whatever it should be
> called) in the WWW, this sheet also being designed to answer questions
> readers (including, but not restricted to, the press) of the admittedly
> terse IAU Circulars may have.
>
> But, accepting that some people might just be interested in whether
> there might be an earth impact prior to the availability of further
> data, I used, on IAUC 6837, the perhaps unfortunate but deliberately
> not wholly quantitative phrase "Error estimates suggest that passage
> within 0.002 AU is virtually certain". Note in particular the word
> "suggest". Is that a word one uses when he is absolutely convinced of
> something? Sure, this was perhaps a "1 sigma" when it might have been
> better to consider a "3 sigma", but is that the end of the world (pun
> intended, I suppose)--given that Karri Muinonen estimated the
> probability of passage within 0.002 AU to be as high as 90 percent?
> No, Clark, my calculations were not "faulty". I did not even
> misinterpret them. Whether I used "ill-chosen" words is a subjective
> judgment--especially if you want to consider that I am writing this
> whole document on April 1.
>
> "The chance of an actual collision is small, but one is not entirely
> out of the question." Given that the press information sheet was put
> together more hastily than the IAU Circular, this statement is perhaps
> also somewhat unfortunate. I have agreed that it is VERY DIFFICULT to
> bring the object within 0.00019-0.00021 AU of the earth in 2028--on the
> basis of the 88-day arc. But as recently as March 28, Muinonen and
> Chodas were STILL arguing about whether an actual collision was
> POSSIBLE. Until this argument is resolved, it is impossible to say
> whether the probability of impact was precisely zero or not.
>
> Don Yeomans' e-mailed request for observations of 1997 XF11 reached my
> computer at 17:45 EST on March 11. That was after "normal office
> hours" (whatever they are!), but I did in fact send them as soon as was
> practical, together with a friendly note to both him and Paul Chodas,
> at 19:32 EST (hardly a terrible delay under the circumstances, surely),
> saying I "shall be interested to hear what you find, [but] the whole
> point is to get ... possible images from old plates". Chodas had
> already indicated to me that he wished "to compute a formal probability
> of impact". Sure, I could be "interested" in this result, but it
> obviously would not be the last word. In any case, when Yeomans, in a
> message that was widely distributed (I received it at 20:15 EST), gave
> the "close approach distance" as "0.00058 +/- 0.00897 (3-sigma) AU", it
> immediately occurred to me that this was a decidedly odd way of
> expressing an uncertainty that just had to be much more "+" than "-"!
>
> Now to the events of March 12. I was up early because I had to be at a
> local television studio for a live program at 7:00 EST. I quickly
> checked the overnight e-mail an hour earlier, noted the requests to
> publish a "correction", to the effect that there could be "no
> collision", and I responded to them at 6:10 EST to the effect that that
> "unmodeled effects surely make [the probability] nonzero. We need more
> data." Back from the studio and--like everyone else--in the thick of
> further press enquiries and interviews, I received from Muinonen (to
> whom I had also sent the March 3-4 observations, as he had requested)
> his assessment of the situation, which was that he obtained a nominal
> miss distance of 0.00033 AU (when I had 0.00031 AU) and was "in
> agreement with" me "that collision with the Earth cannot be ruled out
> at the moment". This was in flat contradiction to Yeomans and Chodas!
> In any case, since I had not even mentioned on the IAU Circular that a
> collision with the earth was a possibility (however remote), what,
> indeed, was the point of publishing a new remark against or in favor of
> this proposition?
>
> Then, around 12:15 EST, I received word that Eleanor Helin and Ken
> Lawrence had images from 1990! It would take a few hours to get
> measurements, of course. On the interview for the CBS Evening News I
> taped at 12:30 I in fact MENTIONED this important new development, but
> I don't know if it were used in the broadcast. It was also around this
> time that I received a phone call from Chapman "ordering" me to discuss
> probability analysis with Chodas and Yeomans. I may or may not have
> mentioned the forthcoming 1990 observations to Chapman: they were
> obviously not of relevance to him anyway, although I knew they would be
> of relevance to Chodas and Yeomans, who would obviously agree with me
> that these solved the problem completely.
>
> We received the March 23 measurements from Helin at 14:00 EST, whilst I
> was again in the midst of an interview, and Gareth Williams had
> computed an orbit showing the 0.006-AU miss distance by the time I was
> driven off again to the television studio at 14:20. Since Paul Chodas
> wrote that he had computed this at 14:49 EST, Williams was clearly the
> first to get this result. But single-night measurements can be
> problematic, and the MPC standards require the data from the second
> night that we knew would be forthcoming. The March 22 measurements
> arrived around 17:00, about the time I got back to my office, and
> Williams had completed the definitive computation, again with the
> 0.006-AU miss distance, within minutes. Amidst further interruptions
> for phone calls and e-mail messages, I then prepared the IAUC 6839,
> finally managing to complete it around 19:30 EST. It was put into the
> CBAT/MPC Computer Service five minutes later, e-mailed to subscribers
> over the course of the next 15 minutes and was available for FREE
> viewing on the WWW at 19:55.
>
> At 20:00 I participated in two more television interviews, including
> one for the next morning's NBC "Today Show", here in the office. The
> crews left shortly after 21:00, and I received notification of the JPL
> orbit computations, obviously identical with ours, at 21:20. On
> arrival home at 22:15 I did yet one more radio interview, for CBS news,
> while eating the dinner my wife had prepared for me hours earlier (how
> did we manage before microwaves?), this then signaling for me the end
> of what had been--and obviously not just for me--a rather strenuous
> day... This feeling is compounded if one realizes that the combined
> scientific expertise for the IAUCs and the MPCs is contained in just
> three people, one of whom was on sick leave for part of March 12. Our
> part-time secretary stayed late to field calls. Our administrator was
> on vacation for the week. The head of the Smithsonian Astrophysical
> Observatory's public affairs office was also out of town, and this is
> one of the complications that led to the unfortunate circumstance that
> the Press Officer of the American Astronomical Society distributed our
> press information sheet as a full-blown press release on behalf of the
> IAU.
>
> To suggest that the IAU Circulars should be "peer reviewed" and to
> imply that this requires that "all data from the international
> astronomical community should be disseminated as rapidly as is
> technically possible" is a red herring. A formal review process simply
> takes too long. Nevertheless, the editors do frequently consult with
> experts in particular areas, and as a result the number of outright
> errors on the IAU Circulars is actually surprisingly small. Speed will
> often tend to spawn errors, but to produce in a slow and plodding
> manner is not a guarantee that they will be eliminated.
>
> At the NASA policy discussion in Houston on March 17, a couple of
> participants insisted that they needed to have all the astrometric data
> immediately they were received by the MPC, without the need for
> checking. As I pointed out, this is a complete impracticality, in that
> most contributors of data EXPECT that we shall do what we can to verify
> their data. To send out masses of unchecked data, not related to
> specific objects, would cause both mass confusion as well as mass
> embarrassment. For example, just during the past couple of weeks, we
> received an extensive batch of near-equatorial observations that
> omitted the sign of the declination, whether that was in the range 0 to
> +1 degree or in the range -1 to 0 deg. While we were able to sort this
> out before any observations were actually published, this could have
> been a very damaging situation that would also have involved our
> receiving e-mails enquiring about specific problems for months to come.
> In any case, since the interest is in NEOs, to make available 4000 or
> more observations every day would quickly overwhelm the most ardent MPC
> subscriber. Nobody should be under the illusion that our checking of
> the data is a "pet research project of ours". Believe me, we get far
> fewer interesting and publishable results out of it than one might
> think, considering the effort we put into it. Some might instead be
> tempted to regard this activity, carried out by Williams over the
> course of many hours seven days per week, as a thankless task--although
> it is in fact clearly appreciated by essentially all of the observers.
>
> My compromise was that we should be able to make available, generally
> on a daily basis, all new observations of unnumbered NEOs. Such a move
> would have allowed others to keep fully on top of the 1997 XF11
> situation, right from the start. Whether they would actually have DONE
> so is quite a different matter.
>
> BGM, 1998 Apr. 1
>
> =====================
> (3) ON ADOPTING A NEO HAZARD INDEX
>
> From: Gerrit Verschuur <GVERSCHR@MSUVX1.MEMPHISdot edu>
>
> Late last year Sky & Telescope commissioned me to write an article
> related to NEOs for their June 1998 edition, timed to coincide with
> the release of a couple of Hollywood movies on the subject of impacts.
> I completed the article by the mid-February deadline, a week or so
> before the 1997 XF11 furor hit the headlines. Sky & Tel had defined a
> theme for the article: how should the public be informed in the case of
> an impending impact? They specifically asked me to discuss Richard
> Binzel's Hazard Index, something he has written and talked about for
> several years. A Hazard Index could be used to indicate the probability
> of an impact as well as the magnitude of the likely event. If you see
> the Sky & Tel article bear in mind that at the time of writing
> 1997 XF11 was a complete unknown to me. I like odd coincidences, but
> this one was too close for comfort.
>
> The moral of the story is that the NEO community might do well to
> consider the implementation (on an international level) of some form of
> Hazard Index to be used in all future reporting of close passes and
> potential strikes. I fully appreciate that probabilities mean little to
> most lay people, and that is why the use of some numerical scale makes
> sense. Consider the Richter Scale for earthquakes. Most lay people
> appreciate that a magnitude 7 quake is very bad whereas a 5 is usually
> not so significant and that a 3 is not worth writing about. But they
> don't actually have a clue as to what the 3, 5 or the 7 mean in terms
> of absolute energies, say. If some form of Hazard Index for NEOs was to
> be adopted the public might begin to appreciate that near misses are
> common, that misses inside the moon's orbit are less common, that
> strikes by small objects occur from time to time, and that civilization
> destroying impacts are infrequent. The use of a cleverly constructed
> scale may prevent false alarms while also serving to realistically
> communicate a warning taking into account uncertainties in orbital
> predictions at any given time. As Binzel notes, an Index value will
> change over time as the predictions improve with new data.
>
> The International Spacegaurd Foundation or the IAU may wish to take the
> lead in deciding whether a Hazard Index is worth considering, how to
> define such an index, and how toimplement its use in the future.
>
> Gerrit L. Verschuur
>
> PS. Thanks to all those who responded to me survey last year. I used
> some of your input in the above-mentioned article.
>
> ====================
> (4) AXIOM ON PUBLIC ANNOUNCEMENTS SHOULD BE APPLIED INTERNATIONALLY
>
> From: Richard Binzel <rpb@astron.mitdot edu>
>
> Dear Benny,
>
> I am a bit surprised by Duncan Steel's response to my proposed axiom
> regarding public announcements pertaining to Earth approaching objects
> for which a collision cannot be ruled out, which I repeat below.
>
> There is nothing in this axiom regarding nationality, control over NEO
> researchers, or censorship. It is an axiom describing a responsible
> code of scientific conduct which can be followed by either professional
> or amateur researchers regardless of nationality.
>
> Sincerely,
> Richard P. Binzel
> Associate Professor of Planetary Science
> M.I.T.
>
> --------------------------------------------------------------------
> "A public statement regarding an Earth approaching object for which
> a collision cannot be ruled out should not be issued without:
>
> a) Giving a quantitative value for the probability;
> b) Having independent verification on this probability;
> c) Placing this probability into the context of the
> collision probability with the background population
> of similar-sized objects."
>
> =====================
> (5) A COMMENT ON DUNCAN STEEL'S "PANDORA'S BOX"
>
> From: Clark Chapman <cchapman@boulder.swridot edu>
>
> Much of what Duncan Steel (April 1 CC Digest) has said about
> the undesirability and impossibility of controlling information is valid.
> But he misses an essential point. The world has long been exposed to
> the uncensored "babble" of anyone who wants to say something and has
> access to a printing press. With the advent of the Internet, the babble
has
> increased to a roar. Yet society, and the scientific community, have
> developed ways to deal with it, to sort out the wheat from the chaff.
>
> Among reputable scientists, that way is to "certify" reputable
> scientific results by having them checked, peer-reviewed, and published
> in technical journals. Associated with that, the scientific community
has
> traditionally regulated itself, by not going to the public media until
the
> date of publication of the peer-reviewed technical article. That
approach
> is *required* by Science and Nature, for example.
>
> Such procedures don't prohibit lay people, amateurs, truthsayers,
> fortune-tellers, pseudo-scientists, and professional scientists who don't
> care about their reputations from publishing their hasty results
immediate-
> ly -- on the Internet, or anywhere -- and such stories are frequently
> reproduced in the supermarket tabloids. But serious people, opinion
> leaders, policy makers, and the like rely on those media (like the New
> York Times, in America, for example) that attempt to abide by society's
> self-regulating procedures in order to report stories with a higher
degree
> of reliability.
>
> No procedures developed in the U.S. or anywhere will prohibit
> casual, unchecked results from going out. As many people may not
> know, just a few days before the 1997 XF11 affair, there was Internet
> chat of a preposterous claim by some "Russian scientists" (not the
> reputable experts that I know) that the asteroid Icarus might hit the
Earth
> in the year 2006. This story, however, did not create banner headlines
> around the world. Nor should it have done so.
>
> It is appropriate and necessary that serious astronomers, and the
> serious media, adapt to the modern realities of the Internet and
establish
> effective procedures -- essentially peer-review -- to reduce the chances
> that mistakes like 1997 XF11 will happen again. It is appropriate that
> entities like the I.A.U., NASA, the Spaceguard Foundation, and all
> manner of amateur and professional astronomical societies, funding
> agencies, etc. (national and international) adopt procedures to ensure
that
> centuries of traditional peer-review procedures are maintained in the
> current Information Age.
>
> The Minor Planet Center represents itself to be, should be, and
> was taken (by the media) to be a *reliable* source of information,
> representing the astronomical community. All of us, not just the MPC,
> lost some credibility a few weeks ago when failures in the peer-review
> process at the MPC led to the XF11 scare. It is wholly appropriate to
> mandate procedures of peer-review. To be sure, as Steel says, the
> conspiracy theorists -- like those who believe that NASA is suppressing
> information about the "Face on Mars" -- will complain. But that is a
> small price to pay for ensuring that scientists continue to retain the
> amazingly high level of credibility that they currently hold in the
public's
> eye.
>
> Clark Chapman
>
>
>