Does the gate close at 9pm or can we stay past then to watch the comet (we are hoping for 10-11pm comet Neowise viewing)

Usually at state parks they are promo with gate closure.

I don't know only been there for a quick rest stop for the kids and dogs it's a beautiful place to have a picnic

Day use only park.

I don't know. But in general you'll want to leave a park before they may lock you in.