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EZ Science (NASA, YouTube Channel)
EZ Science (EZ Science, Official Website)


Sun : (1) the luminous celestial body around which the earth and other planets revolve, from which they receive heat and light, which is composed mainly of hydrogen and helium, and which has a mean distance from earth of about 93,000,000 miles (150,000,000 kilometers), a linear diameter of 864,000 miles (1,390,000 kilometers), and a mass 332,000 times greater than earth (2) a celestial body like the Sun — Merriam-Webster   See also   OneLook


Roget’s II (, Merriam-Webster Thesaurus, Visuwords


The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy mainly as visible light, ultraviolet, and infrared radiation. It is the most important source of energy for life on Earth. The Sun’s diameter is about 1.39 million kilometers (864,000 miles), or 109 times that of Earth. Its mass is about 330,000 times that of Earth, comprising about 99.86% of the total mass of the Solar System. Roughly three-quarters of the Sun’s mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron.

The Sun is a G-type main-sequence star (G2V). As such, it is informally, and not completely accurately, referred to as a yellow dwarf (its light is closer to white than yellow). It formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center, whereas the rest flattened into an orbiting disk that became the Solar System. The central mass became so hot and dense that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process. — Wikipedia

Sun (Encyclopædia Britannica)

Sun (COSMOS: The SAO Encyclopedia of Astronomy)



Talks about the Sun (TED: Ideas Worth Spreading)
Articles about the Sun (Big Think)



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The Sun, Our Solar System’s Star (Planetary Society)
Our Sun (Lunar & Planetary Institute)

The Life-Giving Sun (Introduction to Astronomy, Wolfgang H. Berger, UC San Diego)

Sun (Eric Weisstein’s World of Astronomy, Wolfram Research)
Solar Atmosphere (Eric Weisstein’s World of Astronomy, Wolfram Research)

Sun (Wolfram Alpha)
Space Weather (Wolfram Alpha)




History of Observation of the Sun (Encyclopædia Britannica)

Voyages to the Sun (Steven J. Dick, NASA’s Chief Historian)

Sun (World History Encyclopedia)


DDC: 523.7 The Sun (Library Thing)
Subject: Sun (Library Thing)

Subject: Sun (Open Library)

LCC: QB 520 The Sun (UPenn Online Books)

LCC: QB 520 The Sun (Library of Congress)

Subject: Sun (WorldCat)




Why Does the Sun Burn Us? (Space Place, NASA)
The Sun (Science Trek)
Sun (Cosmos4Kids)

MERLOT: Multimedia Educational Resource for Learning and Online Teaching
OER Commons: Open Educational Resources



Solar Section (British Astronomical Association)


Sun (NASA Science)
Solar Phyiscs (JSTOR)
Solar Physics (NPR Archives)
Sun (Astronomy Magazine)


Space Weather Prediction Center (NOAA)


Sun (



Here are links to pages about closely related subjects.

Knowledge Realm


Law (Constant) Relativity
Force Gravity, Electromagnetism (Light, Color)
Matter (Microscope) Molecule, Atom (Periodic Table), Particle

Universe (Astronomical Instrument)
Galaxy Milky Way, Andromeda
Planetary System Star, Brown Dwarf, Planet, Moon

Our Neighborhood
Solar System Sun
Terrestrial Planet Mercury, Venus, Earth (Moon), Mars
Asteroid Belt Ceres, Vesta
Jovian Planet Jupiter, Saturn, Uranus, Neptune
Trans-Neptunian Object
Kuiper Belt Pluto, Haumea, Makemake
Scattered Disc Eris, Sedna, Planet X
Oort Cloud Etc. Scholz’s Star
Small Body Comet, Centaur, Asteroid


1.   The resources on this page are are organized by a classification scheme developed exclusively for Cosma.