American astronomer Walter Adams was born in 1876.

Born to American missionaries in Syria, Walter S. Adams spent most of his career as an astronomer working at the Mount Wilson observatory, where he was director from 1923 to 1946. During his tenure at Mt. Wilson, which was home to the two most powerful telescopes during the first half of the 20th century, the observatory was central to the study of the sun and stars. Using the spectroscope, he and his colleagues investigated sunspots and the rotation of the Sun, discovered ways to compute the velocities and distances of thousands of stars and identified elements in various planets’ atmospheres. Adams identified the first white dwarf star, and his work in measuring gravitational elements of the star served as proof for Einstein’s later published theories of relativity.

Science NetLinks
In a three-part series of lessons on sunspots, students learn how our knowledge of the universe must be inferred through the use of scientific tools. Specifically, students study sunspots through the use of solar imaging from satellite instruments currently circling the sun (Yohkoh and SOHO satellites).

In Sunspots 1: A Look at Sunspots (9–12), students are introduced to sunspots and the types of technology and solar imaging that can be used to collect information about the sun's features.

In Sunspots 2: Correlating Sunspots to Active Regions (9–12) and Sunspots 3: Tracking the Movement of Sunspots (9–12), students participate in activities in which they apply information gathered by scientific instruments (telescopes and satellites) to infer knowledge about the behavior of sunspots.

It's Gravity (9–12) helps students develop ideas about the enormous impact that gravity has on the universe—the shape and movement of the planets, the solar system, stars and galaxies.

In Star Search (K–2), students observe stars in the night sky and are encouraged to stargaze on their own.

In How Old Are the Stars? (9–12), students determine the age of a star cluster by observing, measuring and plotting astronomical data. They examine the Jewelbox cluster, located within the southern constellation Crux, and determine its age using a relationship between temperature, color and luminosity.