Samuel Pierpont Langley (August 22, 1834 - February 27, 1906) was an American astronomer, physicist, inventor and pioneer of aviation. He helped in the development of astronomically derived and regulated time distribution services in America through the later half of the 19th century. His work with the railroads in this area is often cited as central to the establishment of the Standard Time Zones system. In 1867, he became the director of the Allegheny Observatory where he produced hundreds of drawings of solar phenomena, many of which were the first the world had seen. As an aviation pioneer he attempted to make a working piloted heavier-than-air aircraft. His models flew, but his two attempts at piloted flight were not successful. In 1888 he published a popular science book entitled The New Astronomy, with a strong emphasis on recent developments in solar physics, which gained a very broad readership and did much to popularize the rising science of astrophysics. He also invented the bolometer, an instrument for measuring infrared radiation. He died in 1906 at the age of 71.