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Giannantonio,

Good that you observed about 100 km north of the predicted centreline.

Adriano Valvasori observed from Bologna, almost on the centreline, and reported a negative result.
So the actual shadow must have shifted.

The comet outburst strongly twice only a few days before the occultation so it is not simple to do the photometry as with the usual stellar occultation by an asteroid - a point source of light.
If you have the FITS images say +/- 30 seconds of the predicted time, I can do the photometry to see if any frames showed a significant decrease in light.
The predicted uncertainty in the time of the event was 10 seconds.

Currently we are looking at a large shift south for the shadow track since a report of a 3.1 s occultation has been received from Greece.
I would like to obtain FITS images of that apparent positive event as it is important to measure the photometry using a selection of photometric aperture sizes to see how the result changes. It is also important to select a specific area of sky for the background that is not too contaminated by the outburst coma. Software that uses a nearby annulus for the background sky can or that autocentres on the pseudonucleus can be fooled and give an incorrect result.
Your data will help limit the possibility of any shift of the shadow to the north direction.

Well done,
Richard

-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Gianantony Milani via groups.io
Sent: 08 February 2025 10:30
To: [email protected]
Subject: [29P-ml] 29P occultation

Dear All,

I also observed on Feb. 5 from Padova (Italy), theoretically with a low probability of observing the event being roughly a hundred kilometres further north of the planned occultation zone. Due to my limited equipment (15 cm) I had to use 2 sec. expositions to achieve enough signal, too long for a detailed monitoring.

In the limits of my observing conditions the occultation is negative.

Giannantonio Milani