Has anybody been able to plot the position of Asteroid 45 (Eugenia) in
CdC? It's supposed to occult a star this Saturday for observers in the
southern USA / northern Mexico.

Seems like it should be simple enough, but I get a result that can't
be right. Way too far south, wrong time of day. Meade's skychart
program however does it correctly, it seems.

I went to "select catalogues and display conditions," clicked on
asteroids, clicked on ASTORB, clicked on Asteroid Elements, clicked on
Connect, it apparently got its data from the internet. Clicked on
Refresh, there it is. 

Elements are allegedly
Equinox 2000
e 0.0820015
Incl. 6.60921
Epoch 2006123
Peri. 85.32884
a  2.7206735
M. anomaly 132.94224
Node  147.93682

But. When I plot that for right now, I get
Date  RA:  20h41m54.34s   DE:-15°19'03.1"
and it's not even above the horizon in the evening, as it should be.
It should be way higher than -15. 

Meade's Autostar Suite comes back with
RA  04:54:52.218    Dec  +16°59'34.72"
Which is a lot more reasonable because it's very close to the star
that will be occulted.

Here's what the Meade program is using. Some items are identifiable
and reasonably close to the above data. 

000045 2000 2451857.4975379  2.4949257  273.1761420 2453101.5 
85.4973830 147.9611550   6.6121170 0.083071390 2.720959570   7.46  0.1
0.66 C  Eugenia (45)

Did one of these two somehow get corrupted data, and the other didn't?
Am I somehow downloading an ephemeris in a wrong format?

Or is there a problem because these orbital elements date back to 2005
(no more recent ones on ASTORB yet for #45)?


Hmmm... Just checking... Meade gives coordinates for Ceres (1) as
RA 03:20:40.144
Dec  +16 50 10.86

while CdC using ASTORB gives
RA:  23h15m07.05s   DE:-13°24'03.0"


Most definitely not right. So it's not just the one that's incorrect.

But, if I go to CdC and instead of Astorb, use CBAT, I get these
coordinates for Ceres:
J2000 RA:   3h21m15.28s   DE:+16°55'28.0"
Date  RA:   3h21m43.00s   DE:+16°57'12.6"

Much better. OK, so apparently I can't use ASTORB. But why? Is there a
known problem with the ASTORB database? 


Pete 



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