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From: TerryMoselaol.com
Date: Fri, 29 Jul 2005 14:25:46 EDT
Subject: ANOTHER 'PLUTO'?

Hi all,
 
ANOTHER 'PLUTO'? A new Trans Neptunian Object (TNO) has just been  
discovered, and it may be even larger than Pluto!
 
Thanks to Martin Murphy at Armagh Observatory for the following  
hot-off-the-press info!
 
Jose-Luiz Ortez has found a very slowly moving object while carrying  out a 
checking of
some of the oldest images from the modest TNO survey  that they started in  
2002.

www.iaa.es

The  object was very bright in their images (m_V~17.6!!) so they were able  
to precover it, and also recover it.

According to their best orbit fit  and using regular assumptions on phase 
angle correction, the H value is around  0.3. Unfortunately they do not know the 
geometric albedo but if below 0.25  (which is the case of all TNOs for which 
an albedo has been measured except  Pluto), the object would be larger than 
Pluto. However, it may well happen that  this object is abnormally bright (with a 
very high albedo), like Pluto. So,  depending on the albedo, this object 
might be sort of a Pluto's brother or  Pluto's father...

This object is beyond Pluto and almost reachable by  most amateurs! It is 
observable right after sunset for a while at a reasonable  elevation. Maybe some 
decent science can still come out of your  observations.

Enjoy it!.

Our findings have been sent to the MPC,  but the object has not received
a provisional designation yet. Some ephemeris  are given here:

Ephems (geocentric) [Date, RA, Dec, r, delta, elongation,  mag]:
20050728.00000 13 21 50.208 +20 7 53.62 51.605 51.239 68.32  17.47
20050729.00000 13 21 51.856 +20 7 14.56 51.619 51.239 67.49  17.47
20050730.00000 13 21 53.576 +20 6 35.29 51.632 51.239 66.66  17.47
20050731.00000 13 21 55.369 +20 5 55.81 51.646 51.238 65.84  17.47
20050801.00000 13 21 57.233 +20 5 16.13 51.659 51.238 65.01  17.47
20050802.00000 13 21 59.169 +20 4 36.26 51.672 51.238 64.19  17.47
20050803.00000 13 22 1.176 +20 3 56.23 51.685 51.238 63.37  17.47
20050804.00000 13 22 3.253 +20 3 16.02 51.698 51.238 62.55  17.47
20050805.00000 13 22 5.401 +20 2 35.67 51.711 51.238 61.73  17.47
20050806.00000 13 22 7.619 +20 1 55.17 51.723 51.238 60.92  17.47
20050807.00000 13 22 9.906 +20 1 14.54 51.736 51.238 60.11  17.47
20050808.00000 13 22 12.261 +20 0 33.79 51.748 51.238 59.29  17.47
20050809.00000 13 22 14.685 +19 59 52.93 51.760 51.238 58.49  17.47
20050810.00000 13 22 17.176 +19 59 11.97 51.772 51.237 57.68  17.47
20050811.00000 13 22 19.734 +19 58 30.93 51.784 51.237 56.88  17.47

The orbital elements are:

OSNT11 Epoch 2005 July 29.0 TT =  JDT 2453580.5
M 197.97485 (2000.0) P Q
n 0.00345428 Peri. 239.53682  +0.91285785 -0.07597426
a 43.3408541 Node 121.89008 +0.13526717  +0.98332108
e 0.1887862 Incl. 28.19395 -0.38521856 +0.16524998
P 285.33 H  0.2 G 0.15 U 2

--
Jose-Luis Ortiz
Instituto de Astrofísica de  Andalucía, CSIC
P.O.Box 3004. 18080 Granada. Spain.
..............................................................................
............................................
 
This object is within reach of modern CCD /digital imaging on a good  amateur 
telescope, so why not have a go for it? It's in Coma Berenices, not too  far 
from Arcturus, so it's getting lower in the W as the sky darkens each  
evening. 
 
Clear Skies
 
Terry Moseley

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Last Revised: 2005 August 1st
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