https://www.siliconvalley.com/2024/11/06/theres-a-hidden-white-tower-in-the-palo-alto-hills-used-to-study-the-sun/

Hidden in plain sight along one of the Peninsula’s most popular hiking trails is a geometrically funky tower, where scientists have been quietly collecting solar measurements for nearly 50 years.

Built in 1975, the Wilcox Solar Observatory was part of a Navy project to study the sun’s magnetic field. The sun’s corona spews out a constant stream of charged particles, a solar wind that reaches speeds of up to a million miles an hour as it spreads those particles across our solar system.