Jean Lecacheux wrote at PLANOCCULT ( 2015 March 08):
On next Thursday March 12 around 01:08 UT, the asteroid 216
KLEOPATRA will occult a V= 8.1 HIP(parcos) star in the Crater
Kleopatra is especially interesting for occultation observers, as radar
observations from USA some years ago have shown that this is a
bilobed body, somewhat like a giant version of the comet „Chury“
or the earth-grazer 4179 Toutatis !
Many fundamental questions – midway between celestial mechanics
and geology – are pending about the neck connecting the two lobes.
Is it a solid and steady rocky bridge, or on the contrary a crumbly
swarm of debris between the two components of a quasi-contact
binary asteroid ?
Thanks to Trebur Observatory and to the „CdR&CdL“ photometric
community [cf. http://obswww.unige.ch/~behrend/r000216a.png ],
I am able to predict that the long axis of Kleopatra’s shadow will move
at occultation time nearly perpendicular to the occultation track.
So it should result almost ideal conditions for recording the neck outline !
My following detailed predictions are somewhat different from those
we are currently reading in Preston’s update or in ‚OccultWatcher‘.
Instead of diameter = 122 km, read : apparent long axis ~ 185 km.
Instead of pathwidth = 237 km, read : pathwidth ~ 360 km.
Instead of duration = 8.0 seconds, read : duration ~ 5.5 seconds.
The following map shows the paths of the three bodies according to Steve Preston’s prediction and Jean Lecacheux’s analysis of the photometic data.
(Map: O Klös)