Astronomy Online

Report on the Solar Eclipse on October 12, 1996

Update about Solar Eclipse - School Project (November 11, 1996)

Mogens Winther, Soenderborg, Denmark

The Solar Eclipse reached almost 40 percent in Portugal. This marvellous image series is courtesy of Antonio Cidadao, Portugal, who handled all the observational tasks singlehandedly - including broadcast of the eclipse on the Internet as desrcibed below. The times for the different images are here (in UT): 13:11, 13:16, 13:21, 13:27 13:30, 13:36, 13:41, 13:46, 13:52, 13:56, 14:01, 14:06, 14:11, 14:16, 14:21, 14:26, 14:31, 14:36, 14:41, 14:46, 14:51, 14:56, 14:01, 15:06, 15:11, 15:16, 15:21, 15:26, 15:31, 15:36 and 15:41. Click on the picture to display a larger version (JPEG, 46k).

The October 12 Solar Eclipse will for sure remain a very special event in the minds of the thousands of participating Astronomy On-Line students, teachers, amateur astronomers and professionals all over Europe.

Numerous groups have contributed with both exciting measurements as well as several megabytes of images. A number of links are selected here - in case you find any link is missing, do not hesitate sending a mail to the European Student Project Group.

Parts of Scandinavia were clouded out during the event on Saturday, e.g. Finland, Norway, and parts of Denmark - but most of central Europe was under influence of a high-pressure region entering from the South Atlantic. Bulgaria had heavy fog. In Portugal the morning was very foggy, but the fog lifted just in time.

Astronomy On-Line groups across the European Continent took have now contributed with a large number of very fine observations!

Click to obtain larger picture (JPG, 31k).

As of October 24, the average value of the Lunar Distance, calculated from the reported observations is 412 000 +/- 31 000 km (Standard Deviation). The true value is 390 406 km (geocentric), so this result, obtained exclusively by means of observations done by Astronomy On-Line groups, is less than 5 percent off.

If you want to learn more about these calculations, we suggest that you take a look at the corresponding exercise, II.4 in Try Your Skills Shop.

This is a very impressive result of a unique observational campaign! Congratulations to all contributing groups!

A lot of various methods were applied :

In Xixon - Spain - the Astronomy On Line Groups directly measured the drop in sunlight intensity by means of a homebuild eclipse photometer .

Besides cameras - the classical cardboard tube black box camera was applied too:

Click to obtain larger picture (GIF, 31k).

The Mirror method described in the original AOL eclipse chapters was even more popular. A clear well defined image could be projected out to huge distances - here the Vienna Kuffner Group - in Austria .:

Click to obtain larger picture (JPG, 26k).

In Vienna too - the 6A class from the Kepler-Bundes Real Gymnasium applied this mirror method out to even 27,2 meters. Their measurement of the solar angular diameter deviates less than 2% from the official result !

Similar precise results were obtained by the Orion Group - placed in Ystad, Sweden.

Other groups had mounted Alu-Foil from Alpine Resque blankets in ordinary glass slides in order to mass produce a cheap and safe solar filter.

In Greece a large number of groups were measuring the eclipse with both videorecorders- binocular projections and black box cameras. These groups like other groups in Northern Europe had problems with clouds too -

but they managed to collect data.

Pictures have been provided by the Apollo Group - coming from the Arsakeio School.

In Germany, you may find an interesting link in the images by the: Erlangen Group.

Also from Germany, the group

Click to obtain larger picture (GIF, 51k).

Scivias have provided interesting images - images where the Lunar mountains are visible in silhouette.

In Slovenia students at the Rudolf Maister and the Ljubljana-Sentvid Secondary Schools got amazing pictures - both with conventional techniques and - like here - with a green welding filter in fron of a 200 mm lens:

Notice - this is a combined photo - exposing several images between 13:28.5 UT and 14:05 UT- into the same film. Please notice the successive drop in sunlight intensity - as also observed with the Spanish Fotosensor Group.

Among the best quality images we also find the images by the Slovenia Crni Vrh Observatory - at a 10 cm telescope. For a view at their impressive AOL photogallery- click here.

The PHOBOS group from Murska Sobota, Slovenia also demonstrate a fine collection of scanned images scanned images.

In Portugal the morning was very foggy, but the fog lifted just in time.

Several Scandinavian groups were clouded out - parts of Sweden and Finland - Ireland as well as most of West-Denmark. Norway was covered by clouds and fog too - take a look at their beautiful photos from e.g.. previous midnight sun eclipses.

During the eclipse itself, live pictures were shown some places on Internet.

Both the MIRA and the Copenhagen Site had lot of requests. The Copenhagen Homepage was unique by showing images from several locations simultaneously in Portugal and Denmark. On the latter "Solar eclipse TRANS-Europe observation homepage" Antonio Cidadao from the very active Portuguese Amateur Society APAA (previously partners on the prize awarded EAAE Comet Hyakutake Parallax event - See Sky & Telescope, July 1996) displayed real time CCD images, together with images taken by students from Astronomical Observatory at the University of Copenhagen.

Click to obtain larger picture (JPG, 17k).

These Live Images were followed worldwide - and gave a classical text book demonstration of what astronomers call parallax:

Click to obtain larger picture (JPG, 42k).

In the very end all Denmark got overcast - and the last parts of the eclipse disappeared in clouds too:

Click to obtain larger picture (JPG, 29k).

However- even though the weather was not perfect everywhere- there is no doubt that this has been an experience for many people, students and amateurs across the European Continent.

The size of the craters on the Moon

If you did not think of it yet, we have now a unique way of determining both the diameter of the Moon- as well as the size of selected craters.

If you want to learn more about how this is done, we suggest that you take a look at the corresponding exercise, II.5 in Try Your Skills Shop.

More information

If you want more information, please contact the author of this article, Mogens Winther.