1. The Electro-Magnetic Spectrum
Beyond the spectrum of Visible Light

2. The Electromagnetic Spectrum
Visible Light is only a small part of the possible frequencies for electro-magnetic waves
Radio Waves, X-rays, Infrared Rays etc. differ from Visible light only in
Frequency
Wave length and
Energy

4. The Energy of a Photon
The amount of energy carried by a photon depends on its frequency/wavelength.
The higher the frequency (or the shorter the wave) the more the energy it carries
(see formula on board)
This means that:
Higher frequency E-M waves come from more energetic (that is hotter) sources.
Higher frequency waves carry more energy and are thus more harmful to life.
Causing mutations or even death.

5. Transparency
What an E-M wave can pass through depends on its frequency
Examples:
FM radio waves can pass through solid objects, AM cannot.
Visible Light can pass through glass (and ozone) but UV light cannot.
Thus our atmosphere and magnetosphere allows some waves through but not others..
Thus harmful Gamma rays, X-rays, and some UV light are blocked (but UV now gets through holes in the Ozone layer)
But Telescopes on earth are limited as to what they can “see.”