How bad would it be to run a 500 watt quartz halogen lamp in a open bottom bucket light fixture outside?

How bad would it be to run a 500 watt quartz halogen lamp in a open bottom bucket light fixture outside?

If it's for a restrike lamp it should be fine. If it's going to be the only light source, that's a terrible idea for many reasons. 

I've seen open bottom quartz halogen fixtures, although I think they are a dangerous design.  If any kind of moisture from rain hits the hot linear halogen it could explode and eject hot and sharp glass everywhere.  It's always recommended to run linear T3 halogens in enclosed fixtures only.  With my experience with halogens, I'm surprised I haven't had one self-destruct yet.

As long as you're using the linear halogens in a fully enclosed and water tight fixture outdoors, they will be good to go!