>>Speaking of vacuum, why in the movies, we can see laser and phasers in space. What happen to realizism.
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>True, as A.C. Clarke outlines, IN 2001, on the Moon by the monolith, all you could see of the spotlight was its source and the illumination on its target. On the other hand, you gotta allow the film makers SOME license, otherwise we'd just see pin-pricks of light and then a ship exploding (and you wouldn't even see the pin prick unless the laser was pointing at the camera)

It was from a Authur C. Clarke book (written for teens) that he pointed out that we can not see lasers in space. No matter to reflect off, no visible laser.

By the way, is he still a live?