Eratosthenes figured it out. I don't really know what you mean by this question, though.
It was well before man explored that it was a known fact that the earth was round. The Ancient Greeks had that figured out thousands of years before the first ship hit the water.
Approximately 5 of the Earth's oceans have been explored by humans, while a larger portion of the land has been explored.
Hubble has never "explored" Neptune. It is a telescope in orbit round Earth and from Earth it has "imaged" Neptune. It has done this several times eg 1996 and 1998 (there may be more times!).
PORN
none
umm: "The Earth is round"? ------------------------------------------------ The Earth is not round - it is an oblate spheroid. ---------------------------------------------------------------------------- A (slightly) oblate spheroid seems pretty "round" to me.
Pythagoras stated the earth was round
Yes, it is a fact that the Earth is round.
The moon rotates round the Earth.
There are wonderful pictures from space of earth. In them you can see it is round. The Ancient Greeks knew it was round.
he found out the earth was round when he studied geography
yes he should no because, he explored almost half of the world!!