Hello, we have time to take our 4 & 6 year olds to one museum in SF enroute to Disneyland at the end of Feb. Can someone compare the Exploratorium to the Discovery Museum? Looking at the websites, I thought the outdoor area of the Discovery Museum looks fun, but it seems everyone talks about the Exploratorium as the place to go. Is it more for an older audience though? Also, I see that just outside of SF is a NASA facility with a visitor's centre. Is that worth a stop as we head south? My youngest is totally into planets/space etc, but I read somewhere there's not much to see there? Thanks!