Some questions, and answers, about this projects.

How to choose a partner school?

You can choose any school you want. If you don't have a previous partner, you can use your database account ( (with user name and password sent) and consult the list of participants. The list includes contact details.

Can I associate with more than one school?

If there are no restrictions. Only if you wish to know other schools in the world.

Does my partner have to be in my school's meridian?

That isn't required. The longitude doesn't matter.

What is the minimum distance between schools?

The distance between the parallel passing through each school should be bigger than 400 km. The greater the difference, the lower the error.

What day should  I measure?

Any in between 15/09/2014 and 26/09/2014. The two schools should be measured on the same day. You can repeat the measurement several different days and exchange data with several schools that have been measured on the same days.

At what time do I measure?

At solar noon. That means when the shadow of the gnomon is at the minimum size. You can measure the exact hour on previous days and at the day of the true measurement took several measures before and after at regular intervals after the smallest possible. You probably can know your solar noon from your national observatory.

Do I have to load the data from the web?

Yes. Up to five measurements. Loading data to the database (with username and password sent) is required independently crossing measures that all schools want bilaterally so that we can have a global measurement of Earth's Perimeter done by all schools.