My father used to have a colour atlas and on one of the pages there was a photograph taken from space which seemed to show 3 bright spots (almost like mirror type reflections) at a point on the earth where the Great Pyramids are located.. Could it be possible that the larger pyramids of Egypt could be viewed from space?

I once read in a book, a theory, which states that if one were to dig to the centre of the Earth in a straight line, then you would find yourself digging around the core.

Is this scientfically true and, if so,why? 

I know the earth's orbit around the sun is in the shape of an ellipse.

The sun is one focal point, but what is the other.

Baffled ! :)

Is it possible for a human to visit that place? Or would their mere presence cause the sound to increase to the point where it is no longer the quietest place on Earth?

What makes the sky change colour at different angles and directions?

a: Where does the sky get its colours/gradient come from?

b: Why is the sky blue above and red towards the horizon? Why not the other way around?

Thanks!

If the Moon lost orbit somehow for whatever reason, how would the timeline of the crash look like.

I'm thinking of these ingredients:

- slowly dropping free fall

- at some point it will enter atmosphere, what happens to the Moon?

- tidal waves, will the Moon break up and would cities be flooded during downfall

- say the Moon crashed into solid land, wat kind of crater would it leave, what would it do the the immediate surrounds (shockwave?)

- what happens to the atmosphere if anything at all, and what about the magnetic field?

- will humanity survive or perish, and by what cause?

We assume that life possibly came to Earth through the landing of a relatively large body of mass from somewhere else in the cosmos.  Could the inverse happen?  Could a large volcano (or any other natural means such as storm pressures or atmospheric disruptions), have sufficient energy and force to eject material from our planet (no matter how small a fragment, but sufficient to contain and protect bacteria) to send life onto somewhere else (no matter how improbable)?  Could Earth be a staging post in life's spread further across the universe?