Archive for the ‘Occultation (216) Kleopatra, March 2015’ Category

Duration of positive observation at Kuhlensdorf (France)

Freitag, März 13th, 2015

14:16 UT

Eberhard Bredner has evaluated his recording. He measured an occultation of 4.2 sec.

Negative at Le Rotoir (France)

Freitag, März 13th, 2015

14:15 UT

A negative observation was made by Frederic Vachier at a observing station South of Paris.

Flash observed during occultation at Freiburg

Freitag, März 13th, 2015

10:11  UT

Martin Federspiel announced at his final report a flash of about 1 sec and some flickering during the visual observation of the occultation.

He wrote:

„seeing conditions and image stability generally good, reported flash and flickering of the occulted star very probably NOT due to seeing effects“

Two positive reports from Switzerland

Freitag, März 13th, 2015

09:29 UT

Christof Sauter at St.Margarethen reports a visual observation of 4.4 sec.

Alberto Ossola at Muzzano has measured with video a duration of 3.4 sec.

 

Positive at Owingen (Germany) – 3.5 sec

Freitag, März 13th, 2015

01:44 UT

Bernd Gährken reports a positive observation. He used a Watec with 12.5 fps  with a Newton 150mm.

He has posted a report with images at:

http://www.astrode.de/3kleopatra12.htm

(German language)

A positive visual observation at Simmerath-Rurberg (Germany) – double station – about 4.0 sec

Freitag, März 13th, 2015

2015 March 12th, 23:40 UT

Daniel Fischer, Roland Stoyan and Hans-Georg Purucker reporting positive visual observations with two small refraktors at Simmerath-Rurberg of about 4.0 sec. The timing was made with standard DCF-Watch.

A planned video observation was not successful.

A report can be found at:

https://diary4dan.wordpress.com/2015/03/12/als-kleopatra-einen-8-m-stern-bedeckte

(in German language)

Success and failure at Leiden Observatory

Freitag, März 13th, 2015

2015 March 12th, 22:55 UT

Last night 6 members of the Werkgroep Leidse Sterrewacht reported to join the observation of the Kleopatra event.

Since the 10″ motor drive was repaired, we decided to do the time inserted recording with the 10″. Kees and Piet would operate the Photogrphic refractor and Wim P. and Johan the Lund. I got assistance from Jet. Sander, who would also join, reported sick.

The 10″, the GPS, time inserter and Watec worked properly. However, it was hard to find the star. I did not manage to find it in time. Later, I fould out that the declination circle was not calibrated properly. Therefore, I had been looking in the wrong area. By the time I discovered that, it was too late.

So I was happily surprised that both other groups managed to find the star and to time the occultation. Also Kees managed to record a movie using a compact camera with eyepiece projection. This recording indicates a duration of 4,56 seconds, but does not contain a calibrated time signal.

At the same time, both groups did a visual timing.

Kees and Piet did a timing that is accurate to the second because of the use of the famous Jan Manek ACH-77 device. Wim and Johan have a similar visual timing, recorded on a mobile telephone. This one is slightly later and shorter because of reaction time.

Taking all data into account, I come to the following consolidated timing:

D 01:08:37,00 +/- 0,5

R 01:08:41,56 +/- 0,5

52° 9′ 18,2″ NB

4° 29′ 3.6″ OL

Many thanks to all observers, and also to Sander and Hans who helped preparing this event!

Groeten, Wim

 

Positive at Oberentfelden (CH) – 4.44 sec

Freitag, März 13th, 2015

2015 March 12th, 22:28 UT

Jonas Schenker reports a video measurement with a duration of 4.44 sec.

Positive at Como (Italy) – 3.3 sec

Donnerstag, März 12th, 2015

20:34UT

Carlo Gualdoni reports a video measurement with a duration of 3.3 sec.

Negative at Leeds (U.K.)

Donnerstag, März 12th, 2015

19:59UT

For the Kleopatra event I recorded from 5 minutes before until 5 minutes after the predicted time, to also check for Alexhelios, Cleoselene or any other companion. No big drop in magnitude was detected within this time window using 0.02s exposures.
Congratulations to everyone who recorded a positive observation and my commiserations to those who were clouded out or had technical problems.
Clear skies,
     Alex Pratt (Leeds, England)