Big bang — The idea that the universe has explosively expanded from a condensed state at some time in the past and continues to expand to this day.

Big crunch — A possible scenario for the ultimate fate of the universe, in which the expansion of space eventually reverses and the universe collapses, ultimately ending as a black-hole singularity.

Biosphere — The global sum of all ecosystems. It can also be called the zone of life on Earth.

Black dwarf — A hypothetical stellar remnant, created when a white dwarf becomes sufficiently cool and no longer emits significant heat or light.

Black hole — A region of space where the gravitational field is so powerful that nothing, including light, can escape its pull.

Carrington event — The biggest solar flare in the 160-year recorded history of geomagnetic storms.

Chandler's wobble — A small motion in Earth's axis of rotation, relative to Earth's surface, which occurs because Earth is not a perfect sphere.

Chaos theory — The behavior of certain dynamic systems whose states evolve with time. Usually highly sensitive to initial conditions (popularly referred to as the butterfly effect).

Colony collapse disorder (CCD) — A phenomenon in which worker bees from a beehive or European honeybee colony abruptly disappear.

Concrescence — An assemblage or a drawing together of a plurality; the production of novel togetherness.

Coriolis effect — An apparent deflection of moving objects when they are viewed from a rotating reference frame. The effect explains why water rotates clockwise in the northern hemisphere and anticlockwise in the southern.

Cosmic rays — Energetic particles originating from outer space that impact Earth's atmosphere. Almost 90% are protons, 9% are helium nuclei, and about 1% are electrons.

Cosmoclimatology — A term coined to describe research that involves a range of disciplines from space physics to atmospheric science and cloud microphysics.

DNA — Deoxyribonucleic acid, a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms.

Eschaton — The end of everything, especially time; the final destiny of the world.

Extremely low frequency (ELF) waves — A band of radio frequencies from three to thirty Hz, used for submarine communication.

Galactic alignment — The alignment of the winter solstice sunrise with the galactic equator. This alignment occurs as a result of the precession of the equinoxes.

Gamma rays — High energy electromagnetic radiation that is produced by subatomic particle interactions, such as radioactive decay.

Geosphere — The densest parts of Earth's strata, mostly consisting of rock and regolith.

Gothenburg magnetic flip — A 180-degree flip in the geomagnetic pole of Earth that happened between 12,000 and 13,000 years ago.

HAARP — The High-Frequency Active Auroral Research Program, designed to conduct experiments on ionospheric phenomena.

Heliocentrism — The theory that the sun is at the center of the universe.

Heliosphere — An elongated bubble in space blown into the interstellar medium by the solar wind.

Ionosphere — The uppermost part of the atmosphere, distinguished because it is ionized by solar radiation.

Kepler's Third Law — The square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit.

Kuiper Belt — A region of the solar system extending from the orbit of Neptune to twice that distance. Similar to the asteroid belt, although twenty times larger.

Local interstellar space medium — The relative density of the gas and dust that pervades interstellar space.

Magnetosphere — A highly magnetized region around Earth that protects the planet from incoming cosmic radiation.

Maunder minimum — The name given to the period roughly from 1645 to 1715, when sunspots became exceedingly rare and temperatures were unusually low. Also known as the Mini Ice Age.

Moore's Law — A description of the long-term trend in the history of computing hardware toward exponential growth in cost performance.

Neutron stars — A remnant that can result from the gravitational collapse of a massive star during a supernova event. Such stars are composed almost entirely of neutrons.

Noosphere — A mental envelope or thinking layer that surrounds the atmosphere of the planet containing the totality of all thought forms.

Novelty — The quality of being new. Novelty Theory claims this quality can be objectively measured.

Ontology — The philosophical study of the nature of existence or reality in general.

Oort cloud — A spherical cloud of comets nearly a light year from the sun.

Orbital eccentricity — A measure of how much an orbit deviates from a circle.

Plasma — Partially ionized gas in which a certain proportion of electrons are free rather than being bound to an atom or molecule. Responds strongly to electromagnetic fields.

Plasmoids — A coherent structure of plasma and magnetic fields. Occur in natural phenomena such as ball lightning.

Precession of the equinoxes — A gradual shift in the orientation of Earth's axis of rotation that traces out a conical shape in a cycle of approximately 25,771 years.

Schumann resonance — A set of spectrum peaks in the extremely low frequency (ELF) portion of Earth's electromagnetic field spectrum.

Seyfert galaxies — A subclass of galaxies with active galactic nuclei that appear to be in the process of exploding.

Strange attractor — The result of a series of bifurcations in fluid chaotic systems. An organizing principle of many fractals.

Sunspot cycles — Sunspots are magnetic storms on the face of the sun that form areas of reduced surface temperature. Sunspot activity follows a cycle that quickly rises and more slowly falls over about eleven years. Significant variations of the eleven-year period are known over longer spans of time.

T-Tauri stars — A class of variable stars found near interstellar dust clouds.

Transient luminous event — A short-lived, fluorescent, electrical phenomenon that occurs above storm clouds; less commonly called upper-atmospheric lightning.

Van Allen radiation belts — Bands of plasma around Earth held in place by Earth's magnetic field. There are two main belts: The inner one is mostly composed of protons; the outer one is composed mostly of electrons.

White dwarf — A small star composed mostly of electron-degenerate matter. The faint luminosity of a white dwarf comes from the emission of stored heat.

Younger dryas — A brief cold climate period approximately 12,800–11,500 years ago, also known as the big freeze.

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