So, i had an out with one of my players. He was saying that with astral sight he'd be able to see through astral forms. In fact the astral form of the earth. I've spent most of the week searching the forum for the answer but have failed, so I'm turning to dumpshock to correct either my player or myself.

Fairly sure the earth appears solid. But even if it didn't what would you see if you could look through the earth? Everything on the other side is too far away to see properly anyway.

That was my argument, but it was an area roughly three stories underground.

Earth astral form is solid and lightly luminous. Explain him that searching for an underground facility this way would be like trying to see something through ten meters of faintly glowing and severely murky water.

Also Earth's aura is somewhat solid, you cannot astrally project and zip through in search of the facility, you have to press through (like an astral barrier) with an extended roll of (meters) difficulty and 30 minute base time ! If you're interrupted, you're stuck and need to roll again to go back, with the additionnal complication of possibly getting lost and runnig out of astral projection time - that means death.

What Dahrken said.

And if that doesn't work:Where does this guy gets the idea that he's able to see through astral forms in the first place? In cases like this, I find it best to make your ruling, explain the logic, and shift the burden of proof to the (crazy) player.

SR4a p192 says you take minus the Force of a barrier for tracking something behind a mana barrier, and seeing how the Earth counts as a pretty high force mana barrier there is going to be little to no way to see through it.

The sun is slightly luminous, tell your player to go stare at it and tell you what's on the other side.

Thanks for the answers this should defiantly help

Space.

Darkness.

(Blind people see dark, right?)

Seeing as you can very easily get lost while moving through the Earth on the astral (p114 Street Magic), I would say that you likely can't see very deeply into it, if at all. In fact, I think you can get lost pressing through as little as 1 meter.

Also, consider that in areas with streets, sewers, underground electrical conduit, basements would likely decrease the visibility as they would not be transparent.

So, to actually see this underground facility I would say that the mage would have to pass through a good amount of earth to get close enough. At the very least a few meters to get past all the man made objects. Just my thoughts.