need reasonable aperture safety for burning man project

I'm making an art car for burning man, its a replica of a star trek shuttle. I'm mounting a 1w green laser inside a motorized telescope mount as a "phaser" for sky displays. For safety reasons, I want to be able to have an aperture shutter to block the beam, operated remotely, so I do not have to wait for the laser to warm up each time its used. I'd be very grateful for any suggestions. Thanks.