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Travel the universe with Dr. Ethan Siegel as he answers the biggest questions of all
The Universe’s normal matter consists, humbly, of atoms.
Every atom’s nucleus contains protons, whose number determines that element’s properties.
Over 100 elements, sortable into a periodic table, are presently known.
Only eight processes occur to create them all.
1.) The Big Bang. The early, hot, dense state first created protons and neutrons.
Only the lightest stable elements, up through lithium (3), fuse this early.
2.) Massive stars. The most massive stars are the shortest-lived.
They quickly explode in supernovae, creating copious elements from carbon (6) through zirconium (40).
3.) Low-mass stars. Lower mass, Sun-like stars evolve, becoming giants.
Before dying, slowly adding neutrons produces elements from strontium (38) through bismuth (83).
4.) White dwarf explosions. Accretions and mergers trigger white dwarf explosions: type Ia supernovae.
These yield elements from silicon (14) through zinc (30).
5.) Merging neutron stars. Kilonovae greatly enrich the Universe.
From niobium (41) through plutonium (94), they create the heaviest natural elements.
6.) Cosmic ray spallation. High-energy cosmic particles blast massive nuclei apart.
Spallation creates the Universe’s lithium (3), beryllium (4), and boron (5).
7.) Radioactive decay. Some isotopes are naturally unstable.
Decays produce technetium (43), prometheum (61), and many elements heavier than lead (82).
8.) Human-made elements. The trans-plutonic (>94) elements are exclusively lab-made.
Only human-caused nuclear reactions create them: all the way up to Oganesson (118).
Mostly Mute Monday tells an astronomical story in images, visuals, and no more than 200 words. Talk less; smile more.
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Travel the universe with Dr. Ethan Siegel as he answers the biggest questions of all