About 20 minutes
Just over 10 miles but it will take about double the time to get there.
Roads wind getting there, so it's about a 20-25 minute trip. Possibly longer at night.
You can see it from the park observation tower, about 9 miles. They're not allowing unscheduled visitors but if you have reservations then you can visit.
McDonald Observatory is about 11 miles northwest of the park, but it is currently COVID-closed to visitors.
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