Skip to content
Geolens

Glossary

417 words used in the labs.

Find a term from the labs, understand the process behind it, and see how it appears in the landscape. Each entry connects an explanation with a real observation and a model you can explore.

Term

Mercator

A conformal cylindrical map projection on which constant compass bearings plot as straight lines. It is useful for some navigation tasks, but areas become greatly enlarged towards the poles. Apparent land areas on it should not be compared directly.

What to look for

NASA Blue Marble imagery reprojected by Mdf into Mercator. Local angles are preserved, area grows towards the poles, and a constant-bearing route plots as a straight line.

Related labs

Map projections →
NASA Blue Marble imagery in Mercator projection, with strongly enlarged high-latitude regions.
Loading photograph

Explore further with USGS water glossary · USGS volcano glossary · NPS glacial geology · NASA Earth facts. Photograph acknowledgements are collected on the Image credits page.