AS AN ASTROPHYSICIST, Harriet Natsuyama spent her entire career focused on the stars. Even when she retired and turned her attention to understanding the prehistoric carving of giant stones, the answers were in the sky.

But it was while investigating one of these megaliths in Japan that she had an earthly epiphany. The stone grouping, chiseled more than 5,000 years ago to chart the course of the sun with incredible precision, was framed by soaring Japanese cedars. Not far was a stream, the source of life for these trees and the ancient people who predicted the summer and winter solstices. Natsuyama became fascinated with the forests and rivers she saw through the train window on her twice-yearly research journeys to the mountains of central Japan.

“It was then that I realized how important trees are,” she says, recalling that first trip to the Kanayama Megaliths site a decade ago. “They give us pure water, pure air, they keep the temperatures cool.”

Back in her Los Angeles home, Natsuyama was already concerned about the climate crisis. So she decided to donate to American Forests, which believes creating healthy forests is essential to slowing climate change. She is now a member of American Forests’ Sequoia Circle, individuals who make annual donations of at least $1,000.

Natsuyama grew up and went to school in Hawaii, where her grand- parents had immigrated from Japan. Eventually, her career in astrophysics took her to California and Japan, where she taught and wrote more than 200 journal articles and seven books.

Since retiring, Natsuyama has co-authored a book exploring the Kanayama Megaliths, discovered in the 1990s, and the people who created them. One thing she’s sure of: They cared for each other and the world around them.“You have this wonderful feeling of being in a nurturing environment,” she says of the natural surroundings that have inspired her. “Being in these forests, you can’t help but feel spiritual. It’s everywhere.”