An equator is an imaginary line around the middle of a planet.
the equator is the longest line of latitude on the Earth (the line where the Earth is widest in an east-west direction)
The equator is located at zero degrees latitude. The equator runs through Indonesia, Ecuador, northern Brazil, the Democratic Republic of the Congo, and Kenya, among other countries
The Earth's diameter at the Equator is about 12,756 kilometers (7,926 miles). At the poles, the diameter is about 12,714 kilometers (7,900 miles). The Earth's equatorial bulge is about 43 kilometers (27 miles).