The Night Sky Viewing area near the Visitor Center (large vehicle parking) is open all night for night sky viewing. No camping is allowed however. The Volcano Road is open to hiking and biking after 5pm in the summer, 4:30pm winter.
the road up to the rim closes at 430. i think this is only for vehicles, as far as i can tell from the website.
The park closed at 4:30 pm local time when we visited in early May. They may have special star viewing nights. I recommend checking their website for closing times before your visit.
Pretty sure this closes. But there's not much around for miles, star gazing should be great.
Unfortunately the park closes well before dark.
You should check the website or call.
After business hours you cannot go up the hill but you could stay at the park entrance for stargazing. I suspect there world be very little too none light pollution.
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