In the beginning (after the first three minutes) there was
only hydrogen and helium nuclei, electrons, and photons1,2
all in the form of a hot plasma expanding and cooling. After
380,000 years or so the universe expanded and cooled enough
allowing the electrons to combine with nuclei forming neutral
hydrogen and helium atoms. The photons (light) were able to
escape. This light stretched to the longer wavelengths of
microwave radiation bathing all of the universe today. We are
bathed in the cosmic microwave background radiation, the
afterglow of the big bang.
1Also neutrinos, sound, and gravitational waves.
2There may have been primordial black holes and other entities
making up dark matter.
- Sun
PP-chain VISUAL
neutrinos
gamma
Surface EM, spans gamma to Radio, Solar wind (charged particles)
Ionizing Radiation (atoms and molecules)
Einstein - Photoelectric effect PAPER
Earth's Magnetosphere (blocks solar wind)
Earth's Atmospheric attenuation (blocks most ionizing EM) VISUAL
- Big Bang radiation (non-ionizing)
- Close by supernovae (disrupt the atmosphere) -- evidence this has happened
- Cosmic Rays (gamma, electron, muons) Aside C-14 VISUAL
- Where are unstable atomic isotopes created
- Radioactivity (chains) VISUAL
Alpha, Beta-, Beta+, gamma
- Natural Occurring
- Fission Reactor Byproducts
- Created for medical uses
- Nuclear Accidents
- Nuclear Fallout
-Dosage
Normal, Typical
Which elements VISUAL
Medical, Dental procedures
Occupational Hazards
Typical background Radiation
Gamma Scintillator and spectroscopy VIDEO
not to worry.
sam.wormley@icloud.com
