history - quick recap

 of energy, frequency, and vibration.

in terms of frequency / vibration...

electric field; magnetic field

1. cosmic rays
2. gamma rays
3. X-ray
4. ultra-violet
5. Visible spectrum
6. infra-red
7. microwave
8. radio

Human eyes see just 0.0035% of the known electromagnetic (EM) spectrum. This sliver is called visible light and spans wavelengths between 380 and 780 nanometers. The remaining 99.99%—which includes radio waves, microwaves, infrared, ultraviolet, X-rays, and gamma rays—remains entirely invisible to us.

Infrared (IR): We perceive the longer waves of infrared radiation as heat on our skin, though we cannot see the light itself.

Radio & Microwaves: These have even longer wavelengths and lower energy; while we don't naturally feel them, technologies like Wi-Fi, radios, and cell phones operate within these bands.

UV, X-Rays, & Gamma Rays: These have wavelengths shorter than visible light and carry high amounts of energy. We cannot physically sense them until they cause cellular damage (like a sunburn or radiation sickness).

in terms of energy / mass...

atoms and molecules: [hydrogen, carbon, nitrogen, oxygen, phosphorus]

compounds: H2O (water), NH3 (ammonia), carbon monoxide (CO), carbon dioxide (CO2), methane (CH4), formaldehyde (H2CO), and polycyclic aromatic hydrocarbons (PAHs), hydrogen cyanide (HCN), alcohols, aldehydes,  PN, and PO

Molecular Clouds: Dense, cold clouds of gas and dust serve as cosmic chemical factories. Over 300 distinct complex organic molecules have been discovered in the interstellar medium using radio and infrared spectroscopy.

Comets: Comets are time capsules holding pristine interstellar ice and dust, highly rich in CHON compounds.

Icy Moons: Environments like Saturn's moon Enceladus feature subsurface oceans and hydrothermal vents that contain all six primary life-essential elements (Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, and Sulfur).

1. stellar nucleosynthesis
2. elements
3. molecules
4. compounds (such as carbs, phosphates, amines, nucleotides)
5. genes (specific sequences of the nucleotides within the DNA/RNA)
6. macromolecules (polymers, such as proteins, RNA, DNA)
7. prions and viruses
8. chromosome (telomere)
9. microorganisms / living cell (bacteria, archaea) - prokaryotic (unicellular; Genetic material is a single circular chromosome that floats in an open, undefined region of the cytoplasm called the nucleoid.; ribosomes for protein synthesis; Reproduce asexually through a simple process called binary fission; may be anaerobic or aerobic) 
10. nucleus
11. living cell (fungi, protozoa, helminths/macroparasites) - eukaryotes (DNA is linear, strictly packaged into multiple chromosomes, and housed inside a protective, double-membrane nucleus. unicellular - amoebas or yeast; multicellular - animals, plants, and fungi; mitochondria - for energy, endoplasmic reticulum - for protein and lipid synthesis, and Golgi apparatus - for sorting and shipping; Reproduce both asexually (mitosis) and sexually (meiosis).)
12. microorganisms (single-celled, anaerobic organisms) aka animalcules
13. multi-cellular organisms

21st century CE started on 1st Jan 2001 AD.