Samuel Pierpont Langley

Samuel Pierpont Langley was one of the most prominent American scientists one hundred years ago.

Langley started his scientific career as an astronomer in Ohio, where he became interested in measuring how much energy the Sun was radiating. He built instruments, called calorimeters, to make these measurements. He built others, called bolometers, designed to make similar measurements on stars. Interestingly, the bolometers Langley built are very similar to the detectors scientists at NASA's Langley Research Center use to measure the Earth's radiation budget.

Langley also became interested in heavier-than-air flight. He convinced the United States Navy to sponsor airplane building and testing, using his design. He competed with the Wright Brothers to build the first manned airplane that could fly under its own power. Unfortunately, Langley lost this contest.

In the middle of his life, Langley moved to Washington, D.C. to become the third Secretary of the Smithsonian Institution. The brick building on the south side of the Mall in Washington (where the Washington Monument stands) was where Langley had his office nearly one hundred years ago. He published a book, called The New Astronomy, that still has many interesting perspectives on solar energy, sunspots, and our relationship with the environment.

As a highly educated scientist of a century ago, Samuel Pierpont Langley was a good writer. He wrote about the astronomy of his time, about his measurements of solar energy and stellar energy, and about his experiments with airplanes. Although his style may strike us a "Victorian", many of the things he thought about are still relevant to us today. This page provides a Table of Contents to some excerpts from a book about The New Astronomy of his day, when no one understood how the Sun got its energy or how hot its surface was, or even what it was made of.