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Novo vreme za Minor Planet Center

Started by Sich, August 13, 2006, 02:21:58 pm

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Minor Planet Center ima zvanicni zadatak da sva posmatranja malih tela Suncevog sistema filtrira, pretoci u orbitalne elemente i da drzi spisak svih malih tela koje poznajemo na jednom mestu koje nam omogucava da znamo tacno gde se ona nalaze. U pocetku to je bio posao gde je na listi bilo nekoliko hiljada objekata, a danas ih ima preko 130000 hiljada. Posao se zaista prosirio.
Svi astronomi koji su postrali ta mala tela, bilo da su profesionalci ili amateri, svoja posmatranja su slala u MPC koj je zaista dobro funkcionsao sad vec decenijama pod rukovodstvom jednog coveak Briana Marsdena koji smatra da je vreme da neko drugi preuzme skilptar od njega. Zeli covek napokon zasluzenu penziju
Evo dela jednog od cirkulara MPC-a

Iz MPC 57381-57382,

This is the last batch of Minor Planet Circulars to be published during
my directorship of the Minor Planet Center: I shall retire at the end of the
IAU General Assembly in Prague later this month.  When I took over the reins
in 1978 from Paul Herget, the first director of the Minor Planet Center, there
were just 2060 numbered minor planets (of which about 20 were lost), and
the observation file amounted to some 200,000 entries.  Now there are 134,339
numbered minor planets (all of which are very precisely predictable) and a
total of almost 40,000,000 observations.  In 1978, (1566) Icarus was famous
for having an orbit that took it to within 0.19 AU of the sun; now there are
four numbered minor planets that go in closer, and two multiple-opposition
objects have just under half the perihelion distance of Icarus.  Then, (2060)
Chiron, the sole centaur, was by far the most distant of the numbered
objects, ranging from near Saturn at perihelion to near Uranus at aphelion;
now the number of known centaurs is dwarfed by the wealth of transneptunian
objects that have been found, one of them, (90377) Sedna, notably having
perihelion and aphelion distances of 75 and 900 AU.  More than 100
multiple-opposition objects have orbits showing the same 2:3 mean-motion
resonance with Neptune that is characteristic of Pluto.  Two of these
``plutinos'' have diameters that are more or less half that of Pluto, raising
anew the question of why Pluto was catalogued as the ``ninth planet''---a
problem now brought to a head with the recognition last year of 2003 EL61,
2003 UB313 and 2005 FY9, more esoteric transneptunian objects that are
indeed very comparable to Pluto in size.

The Minor Planet Center could not have succeeded during the past 28 years
without the two people who have served as associate directors, and I wish to
pay tribute to them here.  Conrad Bardwell moved with the Minor Planet Center
to Cambridge from its previous home in Cincinnati.  As the first person to
computerize the search for identifications between minor planets having short
observed arcs at their discovery oppositions and objects generally observed on
two nights at a different opposition, he had already in Cincinnati been able
significantly to increase the production of multiple-opposition minor planets
beyond the efforts of astronomers who had attempted such work by hand; his
pursuit of this activity in both Cincinnati and Cambridge very specifically
resulted in the recovery of numerous lost numbered minor planets, many of
which had previously only been definitely recorded at their discovery
oppositions.  Thanks also to his meticulous involvement in the preparation of
the  MPC's, this allowed an increase in numberings from (2061) to
(4295)---with only two of the earlier ones still lost---and the number of
completed pages of the  MPC's from 4391 to 15,600 by the time he retired
at the end of 1989.  Bardwell has also maintained a subsequent interest in
minor planets, a noteworthy contribution by him being the identification 1950
DA = 2000 YK66, which led to the numbering of this near-earth object as
(29075) and the recognition that there is a 1-in-300 probability that it
will strike the earth in 2880.  Bardwell still visits the MPC for a couple of
hours most Saturday afternoons and will be celebrating his eightieth birthday
on Aug.\ 11.

On succeeding to the position of associate director, Gareth Williams continued
and considerably extended the automation of MPC activities, something that
was becoming very necessary as the CCD succeeded the photographic plate, and
a new era of sky surveys began with the specific aim of dramatically
increasing the rate of discoveries of near-earth objects.  The deep searches
necessary for making substantial numbers of discoveries in the outer solar
system also began.  The combination made it desirable to introduce the
series of  Minor Planet Electronic Circulars} in 1993.  To ensure the
rapid follow-up of candidate near-earth objects, ``The NEO Confirmation Page''
was developed in 1996, another service that quickly proved highly successful.
Although the MPC's themselves continued to be published monthly, the
concomitant increase in observations of main-belt minor planets resulting
from the use of the CCD made it necessary to transfer the publication of
the observations themselves to a supplement series in 1997 that has
only electronic distribution.  The computer software necessary for arranging
these new features was conceived and developed by Williams, who also in
1997 arranged for the automatic preparation and distribution, at 2 a.m.\ local
time, of the ``Daily Orbit Update''  MPEC} containing all the
orbits computed during the previous 24 hours.  By 2000 it became necessary
to transfer the monthly  MPC publication of orbits to another electronic
supplement.  By 2001 the observations supplement was appearing more
frequently than monthly, and since mid-2003 Williams has single-handedly been
ensuring that it appears weekly.  Although the number of basic MPC's
published is still only some 57,000, there have been more than 175,000 pages of
observation supplements, more than 100,000 pages of orbit supplements and
well over 12,000 MPEC.s.  Williams' impressive efforts at automation
also include the checking of observations directly from e-mail messages as they
reach the MPC's computers and in most cases the actual computation of orbits.
He has also attended to the difficult task of the automatic coherent
extraction of information about the observers and instrumentation used, so
that the actual publication of this information (which is very necessary in
order to give credit where it is due) can be made after very limited further
manual editing.  Williams also found the last two of the lost numbered minor
planets, (878) Mildred and (719) Albert, in 1991 and 2000, respective

Brian G. Marsden

"The only thing standing between me and total happiness is reality." - Douglas Porter