From: "Dr. Margarita Metaxa" Subject: Provisional Eratosthenes report PRELIMINARY REPORT FOR ERATOSTHENES PROJECT The project invites you to measure the circumference of the Earth, using the method that the ancient Greek astronomer Eratosthenes first introduced around 200 BC. From November 7th the project "Eratosthenes" started in collaboration between Danish, Greek, Italian, Czech, Finland and Sweden groups of Astronomy On-Line. 6 groups from Denmark, 21 from Greece, 1 from Italy, 1 from Czech, 2 from Sweeden and 1 from Finland participate at the moment. The problem in that project is the bad weather in northern Europe that does not always allow measurements to be taken. Groups in both Greece and Denmark have measured the sunlight-shadows of 1m ruler at the instant the sun passes the local meridian. Until now we have results from three measurements that gives a circumference of the Earth :39.900 km, 41000 km and 42.000 km -exactly what Eratosthenes found!-to be compared with the official value 40 074 km. This coincidence is of course merely a question of luck - we estimate the real accuracy to be within 10%.=20 In the method we used an ordinary Road Map to measure the North-South distance between Greece and South Denmark and not of course the camel of Eratosthenes! Other schools are eagerly invited to join our group - estimating the diameter of our Globe. Only equipment needed : a shadowkeeper ("gnomon") - size 1 meter or equivalent. You only have to measure the following conditions on local Noon : Shadow length and time for local noon. Ensure the surface is horizontally correct levelled . When you report your measurements then also give in your location. Join us ! More results to appear soon! The Erathostenes Groups: Students from Greece Students from Denmark Students from Czech Students from Italy Students from Finland Students from Sweden Below are the results from the schools in details ********************************************************* DANISH SCHOOLS Sonderborg Amtsgymnasium Sonderborg Astronomy Class : Nov 10 : 313 cm +-7 cm (scaled up from a minor gnomon). ------------------------------------------------------------------------- School: Rosborg Amtsgymnasium og HF-kursus, Vejle Place: Vejle Location: 55dg, 43'N, 9dg,31'E Group: Rosborg Amtsgymnasium-1.a,dk Measurements: 8/11 1996: Length of ruler: 100 cm Length of shadow: 311 cm 14/11 1996 Length of ruler: 100 cm Length of shadow: 346 cm ------------------------------------------------------------------------ School: Sor=F8 Akademi. Time: 13/11/96 Length: 11 dg, 33' E Latitude: 55 dg, 26' N Length of ruler: 100 cm Length of shadow: 311 cm Length of shadow: 312cm ---------------------------------------------------------------------------- Toerring Amtsgymnasium Class: 2x and Steen Petersen Besides that the length of shadow was 3,10 m at 1200 nov. 8th our coordinates are: 55 degrees 52' north, 9 degrees 31' east ---------------------------------------------------------------------------- Nysted Youth School Astronomy Team. the longitude of the chruch in Nysted is stated to 11 deg 44 min> Friday, 08.11, 12.00 MET: Length of shadow =3D 288 cm. Saturday, 09.11, 12.15 MET Length of shadow =3D 297 cm. (cloudy sky until 12.15) Sunday, 10.11, 12.00 MET Length of shadow =3D 298 cm. (beautiful weather !) Wednesday, 13.11, 12.00 MET Length of shadow =3D 298 cm. (cloudy sky, but fair observing conditions) Southeast Lollandia Stargazers ----------------------------------------------------------------------------= ---- School: Bjerringbro Gymnasium Group: Astronomyclass Location: 56dg 23'N, 9 dg 39' E Measurements: 14/11 - 1996 Length of ruler: 100cm Length of shadow: 371.5 cm ************************************************************ GREEK SCHOOLS Arsakeio high school: groups "red giants" and "observatory" town :Athens-Ekali country :Greece longitude:23deg 51.8min latitude:38deg 2.9min date: 7/11/1996 shadow:142+/-1 cm time:12.00 11/11/1996 147+/-1 cm 12.08 13/11/1996 149+/-1 cm 12.09 14/11/1996 150 +/-1 cm 12.09 ----------------------------------------------------------------------- Doukas Schools groups:Thalis,Eydimos,Aristinicos,Aristarchos Monday 11 - Time of measurement 12:08 Local Time, Length of the Shadow: 145cm Tuesday 12 -Time: 12 : 08 Length of the Shadow : 1,45 +(-) 0,02 m Wednesday 13- Time: 12 : 09 Length of the Shadow : 1,49 +(-)0,02 m Thursday 14 -Time 12:09 Length of the Shadow: 1.5m + (-) 0,02m ---------------------------------------------------------------------- 1st Gymnasium School of Ag.Paraskeui groups :Aristarchus,Ptolemy,Hipparhus,Pythagoras Long 23deg 48min 50sec N Lat 38deg 00min 25sec E DATE | TIME | MEASUREMENT(shadow of an 1m ruler) |WEATHER -------------------------------------------------------------------------- | 7/11/1996 | 12.00 | 144cm |greek! 11/11/1996 | 12.08 | 147cm |greek! 12/11/1996 | 12.08 | 149.5cm |fair to bad 13/11/1996 | 12.09 | 150.5cm |greek! 14/11/1996 | 12.09 | 153cm (estimation) |bad 15/11/1966 | 13.00 | 163.5cm |greek! ---------------------------------------------------------------------- Peiramatiko Lykeio Ag.Anargiron group Eratosthenis DATE TIME LENGTH OF SHADOW 7-11-1996 13:00 1420 mm 8-11-1996 13:00 1474 mm 11-11-1996 12:08 1452 mm 12-11-1996 12:08 1472 mm 13-11-1996 12:09 1463 mm 14-11-1996 12:09 1477 mm --------------------------------------------------------- 19 Gymn.of Peristeri Orion group Place: Athenes, Greece Lat: 38.01.00N Long: 23.44.00 E measuring: 11 November, time 12.08 Greece time Length of ruler: 100,0 cm Length of shadow: 147cm Time of measuring: 12 November, time 12.08 Greece time Length of ruler: 100,0 cm Length of shadow: 147cm +- 0.5 cm --------------------------------------------------------------- 2nd Lyceum of Holargos groups:Amphitrite,Ariadny,Voyager B.S.V.A,Iniochos,Aquarius 7/11/96: length of the shadow 140 cm at local noon 11/11/96:length of the shadow 154 cm at local noon ------------------------------------------------------------------- Eniaio Polikladiko Likeio of Ioannina Group: Supernova - Ioannina Place: Ioannina, Greece Long : 20.51 dg Lat : 39.40 dg DATE | TIME | MEASURMENT(Shadow of 1m ruler) --------------------------------------------------------------- 12-11-96 | 12:18 | 158 cm 13-11-96 | 12:19 | 159 cm 14/11/96 | 12.19 | 160 cm 15/11/96 | 12.19 | 161 cm ---------------------------------------------------------------- Ziridis Schools group:ziroid.1 Date Time Shadow length 11/11/96 12.08 158 +/- 2cm 12/11/96 12.08 162 +/- 5cm 13/11/96 12.08 156,5 cm +/- 3cm 14/11/96 12.12 165 cm +/- 5 cm Longtitude/Latitude 38 degrees parallel 23-24 degrees meridien ------------------------------------------------------------------ Hellenic College of Thessaloniki DATE TIME MEASUREMENT 12/11/96 12:08 162cm 13/11/96 12:09 165cm 14/11/96 12:32 169cm ********************************************************************* CZECH SCHOOLS Observational Report Name of Group: OLH Veseli nad Moravou Town: Veseli nad Moravou Country: Czech Republic Long.: 17 22 17 E Lat.: 48 57 16 N Date: 1996-11-09. 12:00:00 CET Distance to Base of Ruler: 2,271 m (from 3 measurements) Weather conditions: good (this day only) ****************************************************************** ITALIAN SCHOOLS School: Liceo Scientifico Leonardo. Group: Kallipolis 1 Place: Giarre(Catania), Sicily, Italy. Location: Lat. 37.44 N , Long. 15.13 E. Time: 11/11/96 , Hour: 12.05 p.m. Length of ruler: 100 cm Length of shadow: 142,0 +/- 0.5 Time: 14/11/96 , Hour: 12.05 p.m. Length of shadow: 145.5 cm +/- 0.5 cm Temperature: 18=B0C. We Calculated the distance Giarre-Vejle (on the same meridian) using these= measures: It is about 2000 km. ******************************************************************* FINLAND SCHOOLS Tahtikercho group from Helsinski Finland ************************************************************************* SWEEDEN SCHOOLS Spr=E5k Fr=F6lundagymnasiet group Texas Yesterday, Thursday 96 11 14 we met the lenght of the shadow of one meter exactly at 12.00 o=B4clock. And we got 3,745 meters. Our teacher thought it was pretty high. And that is true. It was that high. Our long. is 11,55 and the Latitud 57=B039' group Beda Yesterday (11.56 local time - 11.00 UT, Thu. 14/11 -96) we measured the length of the shadow of a 1 meter long ruler and came up with the result : 4,01 meters. Our location is : Longitud 11=B055' Latitud 57=B039' ****************************************************************************