Math

• cosh(x) is the average of e^x and e^−x
• Group homomorphism
• Tetractys
• Hyperbolic function
• Hyperbola
• Quaternion
• Tensor
• Euler spiral
• Aeonium tabuliforme rosette, Golden ratio Phyllotaxis
• Fibonacci spiral approximates the Golden spiral (See Liber Abaci).
• Golden spiral
• Desargues' theorem
• Radian
• birectified 5-simplex, a convex Uniform 5-polytope.
• Tesseract, one of the 6 Convex regular polychorons (4-Polytope)
• graph of Tesseract, one of the 6 convex regular 4-polytopes (Polychoron).

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  graph of the 120-cell hecatonicosachoron, one of the 6 convex regular 4-polytopes (Polychorons).

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  Root system is a configuration of vectors in a Euclidean space satisfying certain geometrical properties. The concept is fundamental in the theory of Lie groups and Lie algebras. (See Differentiable manifold, Adjoint endomorphism, Abstract algebra, and Galois theory).

• Lie algebra
• Spirograph for drawing Hypotrochoids and Epitrochoids.

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  Harmonograph employs pendulums to create a geometric images such as Lissajous curves which describe Complex harmonic motion. (See Fourier series).

• Lorenz system (Lorenz attractor)
• Mandelbrot set
• Mandelbrot set detail
• "Seahorse tail", central endpoint is a Misiurewicz point.
• Mandelbrot set detail
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• Tetrahedron
• Hexahedron
• Octahedron
• Dodecahedron
• Icosahedron

Materials

• Periodic table of the Chemical elements
• Methane, the simplest possible Organic compound.
• Estimated mass flows of fluorine
• Chloralkali process
• Vanadium
• Zirconium
• A billet of highly enriched uranium, author unknown (US Government)
• Bismuth
• Hafnium
• Lead
• Thulium
• Lutetium
• Manganese
• Cadmium
• Chlorine
• Rhodium
• Zinc
• Nickel
• Cobalt
• Rhenium
• Ruthenium
• Scandium
• Hydrogen
• Krypton
• Neon
• Nitrogen
• Xenon
• Argon
• Helium
• Yttrium
• Tungsten
• Tantalum
• Paper autofluorescence
• Niobium
• Molybdenum
• Iron
• Chromium
• Etched vanadium disc
• Osmium
• Synthetic gold crystals at Gold
• Synthetic silver crystal
• Bromine liquid and gas (in an acryllic cube)
• Titanium
• Bismuth
• Continuous casted copper slice
• Biodegradable plastic utensils at Photoelasticity
• Ferrofluid Large Spikes at Ferrofluid
• Eight Allotropes of Carbon
• Aerogel

Physics

• Lagrangian point
• L5 Society
• Cyclotron, Lorentz force
• Gravitation, Spacetime
• Field (physics)
• Magnetic dipole, Magnetic field
• Introduction to mathematics of general relativity
• Gravitational redshift, Introduction to general relativity
• Force field (physics), Gravity well
• Wormhole
• Legendre polynomials,Gaussian quadrature
• Maxwell's equations
• Magnetosphere
• Black hole thermodynamics
• Kepler's laws of planetary motion
• Kepler's laws of planetary motion
• Dye laser, Tunable laser
• Rhodamine 6G
• Diffraction grating
• Gamma-ray astronomy, Fermi Gamma-ray Space Telescope
• Hypervelocity
• Activation energy, Incandescence
• Atmospheric electricity Plasma
• Plasma (physics)
• Plasma globe
• Quark–gluon plasma
• Plasma globe demonstrates Anisotropy
• Maxwell's equations
• Birkeland current
• Entropy

Astro

• Milky Way
• Apollo 17, Earth, 20th century
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• Solar flare, Solar transition region, Sun
• Solar flare
• Sun
• Corona
• Coronal loop
• Kepler's Supernova
• Type Ia supernova SN 1994D, near Lenticular galaxy NGC 4526
• Galactic Center, Milky Way

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  Andromeda Galaxy, nearest Spiral galaxy (Canis Major Dwarf Galaxy is nearest to our Solar System)

• Black hole, Stellar black hole
• Summer Triangle, Asterism (astronomy)
• Deneb, the Alpha star in the constellation Cygnus. Deneb in fiction

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  Cygnus X-1, Astrophysical X-ray source, Cygnus X-1 was the first X-ray source widely accepted to be a black hole candidate.

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  Ultraluminous X-ray source

• Dwarf galaxy

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  Whirlpool Galaxy, a Spiral galaxy of the M51 Group in Constellation Canes Venatici, NGC 5195

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  Inferior conjunction of Venus and Earth. Successive inferior conjunctions of Venus repeat very near a 13:8 orbital resonance.

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  Opposition, Conjunction, and Syzygy in Spherical astronomy.
  See also Astronomical transit, Occultation, and Axial precession (an Euler rotation).

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  Celestial sphere
  See Celestial coordinate system, Right ascension and Declination (like Azimuth and Altitude in the Horizontal coordinate system).

• Obliquity of Earth
• Precession of the Earth.
• Obliquity of the ecliptic
• Theodolite (See Tacheometry)
• Alidade
• Astrolabe
• Planisphere
• Multiverse
• Space habitat, Stanford torus
• Atmospheric electricity, Ionosphere
• 100,000-year problem, Insolation