The Bible is a book of Truth. With the exception of scriptures of prophesy or symbolism, it is a literal Truth. We can rest with assurance that every passage contained is accurate to the degree of the knowledge of the ancient languages by the translators. Each scroll can be read and understood without assumptions or additional outside knowledge.
In Joshua 10, the event described is a literal event, not a symbolic event. Yet the sun and moon stood still.
"Sun, stand still at Gibeon,
and moon, in the Valley of Aijalon. And the sun stood still, and the moon stopped,
until the nation took vengeance on their enemies.
Is this not written in the Book of Jashar? The sun stopped in the midst of heaven and did not hurry to set for about a whole day. There has been no day like it before or since, when the Lord heeded the voice of a man, for the Lord fought for Israel."
The simple explanation for this is that Joshua did not know the orbital paths of the stars and planets. Some believe that he did not understand the earth's rotation and the sun's orbit as compared to the earth's orbit, and that God understood what Joshua said even when Joshua did not fully understand the mechanics.
In our opinion, Joshua did understand. Ancient artifacts uncovered through archaeology have proven that the ancient cultures had a full and complete grasp of the solar system. The newest craze is the Mayans, who have the most accurate solar calendar uncovered today. But the Mayans are not the only ones who had an understanding of the solar system.
The ancient Babylonians also had a very solid understanding of the solar system. The gods they studied were stars and planets, worshipping the sun, moon, and stars. Though their star charts and orbital systems have proven to to be very accurate, there is one major difference in their description of the solar system and ours: another planet.
Though the names differ, the Babylonians have a name for each planet in our solar system, and one extra planet, Nibiru. It is the Babylonian word for "crossing over" or "transition."
Coincidentally, other great cities in the Babylonian empire besides Babylon have the same understanding of the solar system. Ancient Sumerians also include a tenth planet in their description of the solar system, as do the Assyrians.
Yet, our understanding of this tenth planet they describe is limited. What if it were not a planet? What if our solar system contained a second sun?
Let's consider for a moment the words of Joshua. "Sun stand still at Gibeon." "Moon, in the valley of Aijalon."
Why did Joshua identify the sun and moon using earthly locations? Were you and I there, we would have simply said, "Sun and moon: stand still," especially in the heat of the battle.
A modern theory for this event is that our solar system contained more than one sun, and that more than one moon revolved around the earth. It is not too far fetched, when you consider that other solar systems in our galaxy have more than one sun, and many planets have more than one moon.
Had the sun, the one that was over Gibeon, stood completely still it would have dropped out of our orbit. Likewise, the moon that was over the valley of Aijalon would drop out of earth's orbit.
As time progresses, our knowledge and understanding of the ancient world increases. Unlike other religions, Christianity is proven by time and vindicated by science. One day, all things will be made known.
Whether there were two suns, whether there were two moons, whether Joshua did not know and understand our solar system, or whether another fact we have not considered can explain the event, it does not matter. What matters is that it happened. We can rest with assurance that God fought the battles for Israel to the extent that He considered Joshua's battle to be more important than even the solar system.
Our God loves us and protects us!