Visit the EarthView web site to meet the team and learn about the project.

Tuesday, July 20, 2010

Latitude/Longitude Converters

Geographers and other scientists use latitude and longitude to identify places on earth reliably and precisely. Every location on earth has a unique combination of latitude (north or south of the equator) and longitude (east or west of the Prime Meridian). Geographer Matt Rosenberg explains these concepts in more detail in his article Latitude and Longitude: Discover the Secrets of Parallels and Meridians.

Latitude and longitude are each expressed as degrees or fractions of degrees. At the equator, a whole degree can be used to locate a place to within a mile or so -- a suitable level of precision for locating a city, for example. A degree comprises 60 minutes, so that a latitude or longitude expressed in degrees and minutes is precise to roughly 100 feet, which is suitable for a lot of purposes, such as finding a house. Fractions of an arc minute are known as seconds, and again there are 60 to each minute. At the equator, coordinates expressed as degrees, minutes and seconds would be precise within a couple of feet. Fractions of a second might be used for even more precise work, such as the location of property boundaries, the corners of a building, or the location of a well. (The caveat "at the equator" is used above because the surface length of a degree of latitude changes slightly from the equator to the poles because of the oblateness of the earth's shape, and the length of a degree of longitude changes dramatically, down to zero at the poles, because of the convergence of the lines there.)

Followers of this blog may already be familiar with the latitude/longitude lookup utility created by Steve Morse, which allows users to look up addresses and find latitudes and longitudes. What is especially useful about this site is that it does not draw on just one source. It uses various mapping web sites, showing that although each site is precise to the equivalent of inches or millimeters, they are only as accurate as the datasets upon which they are based. For any given address, users may find small or large differences, depending on how large a property is, and how each database treats its proximity to nearby roads.

For various reasons, it is often useful to express latitude and longitude as decimal fractions of degrees, rather than minutes and seconds. This is particularly true if distance or area calculations are being made on the basis of the coordinates. Geographers usually prefer the conventional terms, however. Conversion from one to the other is relatively simple, but it can be tedious. For this reason, the conversion utility from the FCC is particularly helpful. It allows users to enter coordinates in either format (d-m-s or decimal) and convert easily to the other. Another interesting utility allows the distance between two points to be calculated from their respective coordinates.

Have you ever heard that if you could dig a really deep hole, you could get to China? From locations in North America, this would not be the case, even if digging such a whole were possible. Geographers can use latitude and longitude to make a simple calculation of where such a journey would end, by finding the antipode. In fact, for most locations on land, the antipode is in a body of water.

"Earth Sandwich" enthusiasts have made a fun geographic project of marking antipodes by making 8,000-mile-thick sandwiches of the earth, with a piece of toast carefully located on opposite sides of the planet at the same time. A similar hobby is the marking of degree confluence points in the geodetic grid, one of which is located very close to EarthView's home in Bridgewater, Massachusetts.

Monday, July 12, 2010

Photos from Summer of Science program

EarthView team members Dr. Domingo and Dr. Hayes-Bohanan thoroughly enjoyed our visit to the Massachusetts Maritime Academy on July 9 to be part of the Summer of Science kick-off event. (Our team also included geography alumna Monique Buckley, educator and photographer extraordinaire and winner of the Rao Scholarship.) We enjoyed the company of faculty, staff, and students from all six CONNECT campuses who are bringing very impressive Science, Technology, Engineering & Math (STEM) outreach programs to the young people of southeastern Massachusetts. It was great to see so many committed colleagues and students from public higher education contributing to the development of human capital of our region from early childhood through post-graduate education.

We also had occasion to meet some of the area children who participate in the programs, and the CONNECT leaders and other officials who advocate tirelessly for public higher education in our Commonwealth. We had time to take a few photos of our own, but we know other media were present, and we hope to provide links to additional coverage in the next few days.
As EarthView fans know, we will take our giant globe anywhere there is an audience. For this occasion, we rose to a unique challenge, and safely inflated EarthView among the model engines in a mechanical teaching bay.
We were delighted to continue our discussion of K-16 geography education with our own Dr. Dana Mohler-Faria (r), President of Bridgewater State College and with Massachusetts Secretary of Education Paul Reville (2nd from left).
We were also pleased to show EarthView to Dr. Jean MacCormack, Chancellor of the University of Massachusetts-Dartmouth and Admiral Richard Gurnon, President of Mass Maritime and host of this lovely event. 

Saturday, July 3, 2010

Dartmouth Middle students journey to center of Earth

Thanks to South Coast Today for letting the Dartmouth community know about EarthView's June 8 visit to Dartmouth Middle School.

We will be back on the South Coast on July 9 as part of the Summer of Science program at Mass Maritime. EarthView will be open to the public, along with a lot of other great exhibits, from 1 to 3 pm.

Thursday, July 1, 2010

CONNECT Summer of Science -- Friday July 9

RADM Maurice Bresnahan, Jr. Hall
Massachusetts Maritime Academy
Buzzards Bay, Massachusetts

EarthView will be part of  the CONNECT Summer of Science program on Friday, July 9. The Event showcases Science Technology Engineering and Math (STEM) education experiences for K-12 and the importance of science education.

On Friday July 9, from 1 to 3 p.m. at the Massachusetts Maritime Academy in Buzzards Bay, students, families, educators, and science buffs of all ages are invited to experience the kick-off of this year’s Summer of Science. Enjoy some ice cream, enter to win tuition waivers and discounts, and see some of the cool science and technology programs first-hand -- including EarthView!

All are welcome. Please let CONNECT know if you are planning on coming by email to