Today, June 19, 240 B.C.: The Earth Is Round, and It's This Big

June 19, 240 B.C.: The Earth Is Round, and It's This Big.

And this is a big deal for GIS folks. We teach that Eratosthenes was one of the first scholars to calculate the circumfrance of the earth, a basic measurement needed for mapping of the earth to occur. Now there are literally 100's of ellipsoids/spheriods that approximate the shape and the size of the earths surface. These ellipsoids have evolved over time as technologies have advanced and more accurate measurements of the earths shape and size have been made. What's amazing is how close Eratosthenes was to todays estimates of the circumfrance of the earth.

http://www.wired.com/science/discoveries/news/2008/06/dayintech_0619

Depending on the source, it is thought Erathosthenes was between 10 and 20 % off of the 'actual' circumference of the earth. Although, we still debate about the 'actual' circumfrance.

Some reasons it is so amazing how close his calculation were:

• the well in Syene was not at 23.5 degrees (the Tropic of Capricorn) like he thought.


• his calculation of the distance between the well in Syene and Alexandria was not completely accurate

At any rate... it was neat to see this on http://www.wired.com/ last week. I just got the post up after starting on the solstice last Thursday.

INDIA

It is all but official (no plane tickets booked as of yet) - we are going to India this fall.

As part of an iniative to better understand and prepare our community for working in a global economy, this will be the second trip (my first) to India. We will focus on building relationships and learning about the the culture to prepare for workshops we will conduct once we return for businesses and the community as a whole.

I will, of course, be documenting as much of the effort as possible here on this blog... and yes, you'll see a lot of maps and spatial information about the trip here ... as you can see below.


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On this trip will be:

Russ Yelton, Executive Director of Entrepreneurial Ventures and Business Incubation on the Enka Campus of Asheville - Buncombe Technical Community College.

Pam Silvers, Chair of the Business Computer Technologies Department at Asheville - Buncombe Technical Community College.

Pete Kennedy, GIS and Computer Technology Instructor. GIS Certificate at Asheville - Buncombe Technical Community College.

Come back often and see how the planning for our trip is going.

Western Chapter of the NC Surveyor Society

Last night I presented to the Western Chapter of the NC Surveyor Society on the topic of Local Data Sources and Open-Source GIS. The presentation portion embedded in this post is pretty short however the bulk of the time I demonstrated MapWindow (http://www.mapwindow.com/ and some of it's functionality.

Some nice featuresof MapWindow include:

• Create and edit shapefiles
• Projects data - even on the fly - sort of
• has many other vector tools like merge, clip, buffer etc ...
• Can connect to postGIS
• Plugin for exporting to kml
• accepts many data formats
• adding WMS layers

Some links from my presentation can be found here: http://geospatial.wetpaint.com/page/MapWindow+Resources

Surveyors meeting

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This was used as a demonstration of how to select features (parcels) using MapWindow, export to shapefile and convert to KML. This KML was then incorporated into a Google Map and embedded in a blog.

Apple Globe

credit: http://www.kevinvanaelst.com/

NCAUG 2008 Student Scholarship

$300 supporting GIS related activities and research.

APPLICATION HERE

GIS Tech position at the City of Asheville

http://www.gjc.org/gjc-cgi/showjob.pl?id=1209502310