Have you considered using a tripod and doing long exposures (30 mins - an hour?) on Velvia? Slide film is great for night-time shots. The only real downside is waiting around for an hour or so during the exposure. It's just a thought.
That is not an option for the northern lights.....I will end up with a light smear on the sky instead of capturing the dynamics of the aurora....
But for traditional night sky shots, yes......velvia would be lovely.