When the calendar lines up just right, you get a rare double feature: National Public Lands Day and Astronomy Day. It's a chance to explore the landscapes that ground us and the skies that inspire us—all within 24 hours.

National Public Lands Day, held on the fourth Saturday of September, is America's biggest single-day volunteer event for parks, forests, and other shared spaces. Volunteers rake, plant, and pick up litter—all while enjoying free admission to these sites. Astronomy Day comes twice a year, with the fall version offering longer nights and darker skies. The goal is simple: help more people discover the universe. Many parks are far from city lights, making them prime spots for seeing the Milky Way, meteor showers, and constellations without interference. Remote places like Tank Lakes in Washington's Alpine Lakes Wilderness, pictured here, offer exactly that.

This year, why not make it a two-for-one celebration? Hike a trail by day, then trace constellations by night. On National Public Lands Day, you might cross paths with a deer or eagle. On Astronomy Day, your companions could be Orion or Cassiopeia. Different worlds, same sense of wonder.