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From: TerryMoselaol.com
Date: Sat, 30 Jul 2005 21:22:03 EDT
Subject: New Planet + EKBO's; RADIO; Lecture, SHUTTLE

Hi all,
 
1. 'The New Planet', etc:
The following info, kindly forwarded by Prof Mark Bailey, should  help to 
clear up any confusion resulting from the recent discovery of THREE  large EKBO's 
(Edgeworth-Kuiper Belt Objects), also known as TNO's  (Trans-Neptunian 
Objects), or if they are large, they're sometimes called  'Plutinos'.
 
BTW, some people have congratulated me for 'scooping' the  official email 
newsflash announcements by NASA, Astronomy Now /  Spaceflight Now, the BAA, and 
even New Scientist which got its first report  slightly confused!
   I have to say that my quick announcement was entirely due to  the prompt 
emails and T/C from Prof Alan Fitzsimmons! 
 
To summarize: The largest one, "2003 UB_313", reported by M. E. Brown, C.  A. 
Trujillo, and D. Rabinowitz, using the Palomar 1.2-m Schmidt telescope (+  
Quest camera), is believed to be bigger, and intrinsically brighter, than Pluto, 
 and is therefore being called  'The Tenth Planet'.
2003  UB_313, currently at a distance of 97 AU (Astronomical Units - an AU  
is the mean Earth-Sun distance: about 150 million km, or 93 million  miles) 
from the Sun, and a magnitude in red light of 18.5, has  absolute magnitude H = 
-1.1 (Pluto has H = -1.0). The orbital period (its  'year') is 557 years.

The following details from the IAU, forwarded by  Mark, give details of all 
three objects:
 
..............................................................................
...............................................
 
   Circular No. 8577
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://cfa-www.harvard.edu/iau/cbat.html  ISSN 0081-0304


2003  EL_61, 2003 UB_313, AND 2005 FY_9
Three relatively  bright transneptunian objects have been reported by M. E. 
Brown, C. A. Trujillo,  and D. Rabinowitz using the Palomar 1.2-m Schmidt 
telescope (+ Quest  camera).  The object 2003 UB_313, currently at heliocentric 
distance r = 97  AU and red mag 18.5, has absolute magnitude H = -1.1 (Pluto has 
H = -1.0);  observations, the following orbital elements (P = 557 yr), and an 
ephemeris  appear on MPEC 2005-O41.

Epoch = 2005 Aug. 18.0 TT
T =  2257 Jan. 26.1837 TT         Peri. = 151.3115
e = 0.441613               Node  =  35.8750  2000.0
q = 37.808 AU               Incl. =  44.1770

MPEC 2005-O42 contains  observations, orbital elements (T = Sept. 2130, q = 
38.7 AU, Peri. = 246 deg,  Node = 79 deg, i = 29 deg, e = 0.15, P = 308 yr), 
and an ephemeris for 2005 FY_9  (which is currently at red mag 17).

MPEC 2005-O36 contains astrometric observations for an object,  designated 
2003 EL_61, of red mag 17 first reported by P. Santos- Sanz, J. L.  Ortiz, and 
F. J. Aceituno via three CCD frames taken in March 2003 with a 0.36-m  
Schmidt-Cassegrain reflector at the Sierra
Nevada Observatory in Granada,  Spain, with additional observations 
identified from images obtained at several  different sites back to 1955.  MPEC 
2005-O36 also contains orbital elements  (T = Dec. 2133, q = 35.2 AU, Peri. = 240 
deg, Node = 122 deg, i = 28 deg, e =  0.19, P = 285 yr) and an ephemeris for 2003 
EL_61.  This object was  also
found by Brown et al. at Palomar on 2004 May 6 [Rabinowitz et al. 2005,  
Bull. A.A.S. 37(3), Abstr. 56.12], who also obtained observations at Keck  
Observatory during Jan.-June 2005 of a satellite with orbital period 49.1 days  and 
semimajor axis approximately 49500 km, which indicate a total system mass  
approximately 29 percent that of the mass of the Pluto-Charon
system [Bouchez  et al. 2005, Bull. A.A.S. 37(3), Abstr. 56.02; Brown et al. 
2005, Ap.J. Let.,  submitted].


COMET C/2005 N6 (SOHO)
Another  very faint and diffuse tailless Kreutz sungrazing
comet has been found on  SOHO images (cf. IAUC 8576; TC = T. Chen).

Comet     2005 UT       R.A.(2000)Decl.  Inst.   F    MPEC
C/2005 N6   July  6.354    6 54.1   +21 22   C2    TC    2005-O26

(C) Copyright 2005 CBAT
2005 July 29       (8577)       Daniel W. E. Green"
 
..............................................................................
..
 
It's a pity that 2003 UB_313 isn't near perihelion, rather than near  
aphelion: if it was, we could see it in good amateur telescopes!
 
See also: info about 2003 EL61 and 2003 UB313 at 
www.gps.caltech.edu/~mbrown/planetlila


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.............................................
 
2. RADIO:  Thu, 4 Aug, 4.30pm, BBC R4: 'The Material World' on  the Perseid 
meteors.

3. LECTURE: Wed, 3 Aug, 6.00pm, Larkin Theatre, DCU:  Prof. Anders Barany on 
'Einstein's Nobel Prize'.  The fascinating story  behind the award. Booking: 
(01) 700-5382 or ncpstdcu

4: The COLUMBIA  Shuttle Mission: Watch the Shuttle on the Web at  
www.nasa.gov
 
Clear skies,
 
Terry  Moseley


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