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Berkshire, England (1792 - 1871)
Sir John Frederick William Herschel was an English mathematician, astronomer, chemist, experimental photographer and inventor. The son of astronomer Sir William Herschel, he originated the use of the Julian day system in astronomy. He named seven moons of Saturn and four moons of Uranus.





The Glass & Mirrors Toolkit

If you have access to some lenses and mirrors in your school science supply room, this set of demonstration activities will help your students understand more about how telescopes work, the differences between telescopes made with mirrors and those made with lenses, and how we are continuing the tradition of Galileo and Newton in building new telescopes today.

Big Questions

How do telescopes actually work?
Why are bigger telescopes better?
What’s the difference between telescopes made with lenses (refractors) and telescopes made with a mirror (reflectors)?
How are the telescopes of Galileo and Newton similar to telescope designs today?

Big Activity

Using a simple setup with lenses and mirrors, demonstrate how a telescope collects light, focuses it, and then magnifies the image.


Presenters: A minimum of one person.
Visitors: Up to 10 people at a time is appropriate.


About 15 minutes.

The Glass and Mirrors manual is a 34-page PDF file. Click here to download.

Contributed by Astronomical Society of the Pacific.




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