1. Snowflakes and Satellites Jean M. Phillips, Librarian Space Science & Engineering Center University of Wisconsin-Madison July 2006

2. What will we talk about? Snowflakes, 1885: Wilson Bentley, the Snowflake Man and Professor Benjamin Snow Pictures of snow crystals and how they form Snow movie Satellites, 1966: Verner E. Suomi Satellite movie

3. Wilson Alwyn Bentley, 1865-1931 First photomicrograph of an ice crystal on 15 January 1885 How did Bentley take his pictures? What is a glass lantern slide? How many pictures did Bentley take and why did he take so many?

4. Bentley with camera

5. Professor Benjamin Snow Taught physics at UW-Madison until 1925 He learned about Bentley’s “snow pictures” long before 1920 Professor Snow gave “snowflake” lectures about two times per year Later, slides were given to meteorology department and then, to the library

6. What is snow? Snow is precipitation that freezes and collects in clouds When released, the crystals may join together or grow depending on the temperature of the atmosphere All snow crystals start as hexagons Why is it important to study snow crystals?

7. Snow crystal pictures

9. Grow your own crystals http://whyfiles.org/123snow/2.html

10. http://library.ssec.wisc.edu/library/bentleys ql/index.html

11. Father of Satellite Meteorology Verner E. Suomi Inventor of Spin-Scan Camera which allowed continuous viewing of weather from space over a large fraction of Earth’s surface Suomi understood benefits of observing single weather events at frequent intervals

12. ATS-I Spacecraft From: The Applications Technology Satellite Meteorological Data Catalog: Volume I)The Applications Technology Satellite Meteorological Data Catalog: Volume I

13. Spin-Scan Camera From: The Applications Technology Satellite Meteorological Data Catalog: VolumeThe Applications Technology Satellite Meteorological Data Catalog: Volume

14. How did it work? Suomi used the spin of the satellite to scan the earth – 2400 satellite revolutions needed to produce one Earth image The camera scanned a small strip of the Earth with each rotation, tilting slightly for the next rotation (or line of the picture) One Earth image created every 20 minutes

15. Why is it important to know what the weather will do?

18. 18 November 1967 Movie

20. How we view satellite images today http://www.ssec.wisc.edu/~tomw/w isgifloop.html http://www.ssec.wisc.edu/~tomw/w isgifloop.html