Central Bureau for Astronomical Telegrams
IAUC 9110: NOTICE TO SUBSCRIBERS; EDITORIAL NOTICE; P/2010 A2
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Circular No. 9110
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
URL http://www.cfa.harvard.edu/iau/cbat.html ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)
NOTICE TO SUBSCRIBERS
N. Brickhouse and C. Alcock, Smithsonian Astrophysical
Observatory (SAO), write: "As of 2010 Feb. 1, the SAO will no
longer be hosting the Central Bureau for Astronomical Telegrams
(CBAT) for the International Astronomical Union (IAU) because SAO
has been unable to obtain sufficient funding to sustain the CBAT
financially. The CBAT is working, with the support of the IAU, on
a transition to a new sponsoring institution. As of this
announcement, SAO will not accept new subscription money and
expects that the CBAT will announce soon the revised arrangements
for subscription payments. During the interim period, SAO will
not be able to accept subscriptions."
EDITORIAL NOTICE
The IAU, through its General Secretary, confirms that the CBAT
will continue to operate with the undersigned as Director and that
every effort is being made to ensure no disruption of the CBAT's
activities during the transition to its new home. Correspondence
now can be sent to the Director via e-mail to
dwe_green@eps.harvard.edu and via postal mail to: Dr. D. W. E.
Green; Room 209; Department of Earth and Planetary Sciences;
Harvard University; 20 Oxford St.; Cambridge, MA 02138; U.S.A.
COMET P/2010 A2 (LINEAR)
Z. Sekanina, Jet Propulsion Laboratory, writes that the
orientations of the tail of this comet reported from the
observations made between Jan. 7 and 16 (IAUC 9105, 9109; CBET 2134)
suggest its formation between January and August 2009. Because of
the edge-on projection (with the earth only 2 to 3 degrees below
the comet's orbital plane) it is not possible to decide whether the
tail is a product of one or more brief emission events or
continuous activity over a period of time. From the tail's length,
the maximum solar radiation pressure acceleration exerted on the
dust is estimated at about 0.1 percent of the solar gravitational
acceleration, which implies that the smallest dust particles in the
tail are about 1 mm in diameter (at an assumed density of 1 g/cm**3).
From the width of the tail, a lower limit on the normal component
of the particle velocity is about 0.1 m/s. An improved estimate
can be determined from the tail width around the time of the
earth's crossing the orbital plane on 2010 Feb. 9.
(C) Copyright 2010 CBAT
2010 January 25 (9110) Daniel W. E. Green
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