05 JUNE: PUBLIC OBSERVATION OF EXTRASOLAR PLANET TRANSIT

[vossinakis]

AN INVITATION TO WATCH THE TRANSIT OF EXTRASOLAR PLANET XO-3b FROM EUROPEAN ASTRONOMICAL OBSERVATORIES ALL AMATEURS ARE WARMLY INVITED TO SHOOT THE TRANSITS WITH PROPER TELESCOPES!

 

http://www.crabnebula.it/web/diretta_brera.htm

http://www.crabnebula.it/web/doc_transits/index.htm

 

VERY IMPORTANT:

 

We have prepared a database to collect all the available information (data and results) about the extra-solar planet transit. You can upload FITS files, set of zipped FITS files, text files and set of zipped text files:

http://www.brera.inaf.it/interroga/dbServer?cmd=xo3b

 

Results of your photometry can be communicated following any format you like. We anyway encourage you to follow the AVVSO extended format http://www.aavso.org/observing/submit/extended.shtml).

 

The finally collected data will be available to everybody and managed by the "Terre del Cielo (Worlds of the Sky) organization. You can freely refer to them for any possible use.

In order to access the database you need to register sending an e-mail to Angelo Angeletti (angelo.angeletti@virgilio.it), Stefano Covino (stefano.covino@brera.inaf.it),

Rodolfo Calanca (rodolfo.calanca@gmail.com) and Paolo D'Avanzo (paolo.davanzo@brera.inaf.it).

 

"WORLDS OF THE SKY" Project intends to approach the great but inexperienced public wishing to visit our Observatories as astronomy “fans” and to watch live an extra solar planet

transit. In details, on next 05th June (starting at 19h UT ) many Italian and European Observatories will place their instrumentation at public’s disposal to “observe” HAT-P-7b planet.

 

The italian astronomer Stefano Covino (Osservatorio Astronomico INAF di Brera - ww.mi.astro.it) writes:

"Observing extra-Solar planet transits is a valuable scientific tool. However, even more than that, it is a fascinating way to look at other worlds. The existence of planets around other stars beyond our Sun has been conjectured since the beginning of human history, and the same idea has also been able to raise fundamental enthusiasms and criticisms in equal percentage. Philosophy, theology and even psychology have been involved to explain the importance of this recurrent idea in human history.Here, we review how since the Hellenistic era the hypothesis of many worlds developed and also describe an international event we are organizing with the aim to secure multi-site observations of a planet transit. WORLDS OF THE SKY Project is an example of science in the internet era".

 

Minimum requirements of the instrumentation

 

The magnitude of the stars displaying transiting planets usually ranges between 8 and 12. Therefore, it’s not necessary to use huge telescopes to detect and study the light curve of a transit with high precision results; nonetheless, first-rate optics, mechanics and electronics are required. Here are some (hopefully useful) suggestions for the choice and use of a suitable equipment:

 

· Telescopes with diameters larger than 15 cm (reflectors, refractors or Schmidt- Cassegrain) can be profitably used. Focal length should not be increased too much, in order to easily find, within the sensor field, the reference stars needed for differential photometry. When necessary, add a high-quality, low-vignetting focal reducer.

 

· The optimum focal length should range between 1 and 2 metres. For instance, a SBIG ST–8 CCD (a 9.2 mm x 13.8 mm sensor), used with a 1-metre focal length, produces a field size 31’x 47’, reduced to 15’x 24’ when focal length increases to 2 metres. With this type of CCD, and using a 1-metre focal length, we can always find one or more reference stars within the chosen field.

 

· The telescope must have an equatorial mounting and be permanently mounted.

 

· Alignment of the polar axis must be as careful as possible, in order to avoid even the slightest field rotation (such an event can easily occur when the telescope follows a star for several hours).

 

· The telescope should be equipped with a first-rate motorized drive. Stellar discs can never be blurred, else precision of photometric measurements will rapidly deteriorate.

 

· An auto-drive device is highly recommended. Without it, exposure times must be reduced, because in this case the driving precision relies only on the telescope drive (remember, however, that a minimum exposure time of 60 seconds is required).

 

· A CCD camera with good photometric performance should have a very low readout noise (i.e. the uncertainty associated to the reading of a matrix photo-element).