Can you prove the heliocentric model of the solar system?

This question came up recently. There are always put downs towards christianity for not accepting this model because of the Bible and so forth. I just wanted to see if anyone can prove this without using modern technology (no spaceships… Continue Reading

How can gas giants orbiting so close to their suns retain their atmosphere?

I’d always read that the inner planets of our solar system once had thick atmospheres like the outer planets but they were driven off by the sun early in their development. Now I read about super gas-giant planets that orbit… Continue Reading