If you want to go up by the cable car, it's open these nights until 01.45, the price is not quite "popular" but if you are in the aerea it's a big experience.
It wasn't possible to photograph, but you can have a look at ;
The best night is going to be from 12-13 of August, and if you can't come this year, try next, this is a phenomenon, that repeats every year, and it can be seen all over the wold, but the best is to search a place without light pollution, and the hights helps to get better vision too.
Have a good and starry night.
Give you some refreshing views rom last winter, and promise to come back to Sierra Nevada this autumn.