I'm working on a GeoTargeting application. I'm curious if longitude and latitude of a point on the earth can change?
If you know the exact position of the statue of liberty how sure is it that longitude and latitude will stay the same.
Does it change according to the season, time in the year, or slowly over time
Yes. Zip codes get split all the time, and doing so would move the center of the zip code to a new location.
47.554 always equals 47.554
But if the shape of the earth changes or you are using different methods of calculations (there are plenty) or if the input data changes in precision or if if your compiler treats floating point differently..
you'll end up in different long/lat
Wikipedia to the rescue:
The surface layer of the Earth, the lithosphere, is broken up into several tectonic plates. Each plate moves in a different direction, at speeds of about 50 to 100 mm per year. As a result, for example, the longitudinal difference between a point on the equator in Uganda (on the African Plate) and a point on the equator in Ecuador (on the South American Plate) is increasing by about 0.0014 arcseconds per year.
It depends on the map projection variables you use. Currently WGS-84 is used mostly.
The same point can have different coordinates depending on the variables. They do not differ a lot, I remember the difference between EUR-50 (or something like that) and WGS-84 was at most 50 meters or something.
You're tangentially referring to geodetics, which is the science of modelling (representing) the shape of the earth. So while a physical location may not change, the datum (model) used by a geodetic coordinate system will change, fortunately this does not happen frequently.
In North America NAD83 is the mostly widely used datum, which replaced NAD27.
Did I mention that Geographic Information Systems (GIS) was my foray into software development?