- Kepler is a short history of events leading to the astronomical discoveries of Johannes Kepler. It was written by Walter William Bryant, a staff member of the Royal Observatory, Greenwich. The book was published in 1920 by the Society for Promoting Christian Knowledge, London, and by The MacMillan Company, New York, within a series of books called “Pioneers of Progress.”
- Deneb (Wikipedia)
Deneb (/ˈdɛnɛb/) is a first-magnitude star in the constellation of Cygnus. Deneb is one of the vertices of the asterism known as the Summer Triangle and the “head” of the Northern Cross. It is the brightest star in Cygnus and the 19th brightest star in the night sky, with an average apparent magnitude of +1.25. A blue supergiant, Deneb rivals Rigel as the most luminous first-magnitude star. However, its distance, and hence luminosity, is poorly known; its luminosity is somewhere between 55,000 and 196,000 times that of the Sun. Its Bayer designation is α Cygni, which is Latinised to Alpha Cygni, abbreviated to Alpha Cyg or α Cyg.