Asteroid occultation on Nov. 19, 2010

[PTS]

Hi,
I've prepared finder charts for this event.
Please also see WC Yue's posting at:

http://forum.hkas.org.hk/viewthread.php ... a=page%3D1


PTS


----------------------------------------------------------
IOTA/IOTA-ES occultation update for
(2649) Oongaq / TYC 1278-00040-1 event on 2010 Nov 19, 15:21 UT
Visible from Alaska, Japan, China, SE Asia


Summary
-------
On 2010 Nov 19 UT, the 33 km diameter asteroid (2649) Oongaq will occult a 12.0
mag star in the constellation Taurus for observers along a path across Alaska,
Japan, China, SE Asia.

In the case of an occultation, the combined light of the asteroid and the star
will drop by 2.7 mag to 14.6 mag (the magnitude of the asteroid) for at most 3.3
seconds.

This update is based on UNSO/Flagstaff astrometry for the asteroid kindly
provided by Alice Monet, historical astrometry from the MPC files (via AstDys),
and the following catalogs for the star position: UCAC.

The event at a glimpse
----------------------
* Rank: 29
* date and approx. time of event: 2010 Nov 19, 15:11 - 2010 Nov 19, 15:32 UT
* magnitude of target star: 12.0
* magnitude drop [mag]: 2.7
* estimated maximum duration [s]: 3.3
* Moon: 96 % sunlit, 38?distance
* Sun: 166?distance
* rough path description: Alaska, Japan, China, SE Asia

The occultation path
--------------------
* approximate projected width [km]: 34
* 1 sigma uncertainty interval [path widths]: +/- 2.34
* 1 sigma uncertainty interval [seconds]: +/- 8.5
* 1 sigma uncertainty interval approx RA,DE ["]: (+/- .110 +/- .061)
* 1 sigma uncertainty ellipse (major, minor, PA): ( .110", .061", 94?)
* approx speed of asteroid's shadow [km/s]: 9.9112
* website for maps:
http://www.asteroidoccultation.com

[Eddy So]

謝謝分享！

[PTS]

The event was recorded successfully last night,
When 256-frame was used on the StellaCam3, stars down to ~15mag were seen on teh screen, including the asteroid.
Snap shots were taken every 30 seonds.
As transparency improved at the event progressed, 4-frame stacking was possible (meaning expsores of ~1/8 second).

The asteroid started to "merged" into the target star around 15:21 UTC, and video recording strated, and ended at about 15:33 UTC. When returning to 128 frame stacking, the asteroid has re-appeared and quite far away from the target star.

However, occultation was not SEEN visually. Detail inspectionof teh video clip will be done later.

PTS