UTM coordinates wrong?

[Justcameron]

Take this cache: http://www.geocaching.com/seek/cache_detai...60-d85a53cc07db

 

Lat/long S 31° 07.903 E 138° 32.361

UTM: 54J E 265381 N 6553194

 

Shouldn't that be UTM: 54J E 265381 S 6553194?

 

If you click "Other conversions..." it gives the completely different N -3446805 which makes no sense at all to me - I thought UTM had false somethings to avoid negative numbers???

[+DavidMac]

Shouldn't that be UTM: 54J E 265381 S 6553194?

 

The way I understand it, it should be correct as shown on the page. UTM doesn't use a worldwide projection that is divided into north/south, but divides the world into a grid of 60x20 zones and uses easting and northing to specify a point within a given zone. So, the cache is in zone 54J, with the easting specifying the number of meters east or west of the center of the zone, and the northing giving you the number of meters north or south of the equator.

Edited April 30, 2008 by DavidMac

[+tozainamboku]

The coordinates above are correct. UTM always shows Easting (E) and Northing (N). The way you tell that you are in the southern hemisphere is the zone 54J. The letters in the first half of the alphabet are used for the latitude zones in the southern hemisphere and the letters in the second half of the alphabet are used for the northern hemisphere. DavidMac almost has it right in his explanation of Easting and Northing except that as you said

I thought UTM had false somethings to avoid negative numbers???

The Easting uses a false origin 500,000 meters west of the central meridian of the zone, so you always add 500,000 to distance in meters east or west of the central meridian. In the northern hemisphere, the Northing is the distance in meters from the equator. But in the southern hemisphere you add a false Northing of 10,000,000 meters to the distance from the equator to get a positive number. Apparently, the "Other conversions..." page fails to add the 10,000,000 to the Northing for the southern hemisphere. Just one more piece of evidence that Geocaching hates Australian chinldren.

[+Lil Devil]

Just one more piece of evidence that Geocaching hates Australian chinldren.

 

 

You made me squirt Root Beer out of my nose.