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NASA Space Place (YouTube Channel)


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 — 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)




Heliophysics means “physics of the Sun” (the prefix “helio”, from Attic Greek hḗlios, means Sun), and appears to have been used only in that sense until quite recently. In the early times, heliophysics was concerned principally with the superficial layers of the star, and was synonymous with what is now more commonly called “solar physics”. Usage was extended explicitly in 1981 to its literal meaning, denoting the physics of the entire Sun: from center to corona, and has been used in that sense since. — Wikipedia

Science Mission Directorate Heliophysics Division (NASA)
Heliophysics Science Division (Wikipedia)

Solar Physics Group (NASA’s Marshall Space Flight Center)

Parker Solar Probe is a NASA space probe launched in 2018 with the mission of making observations of the outer corona of the Sun. It will approach to within 9.86 solar radii (6.9 million km or 4.3 million miles) from the center of the Sun, and by 2025 will travel, at closest approach, as fast as 690,000 km/h (430,000 mph), or 0.064% the speed of light. It is the fastest object ever built. — Wikipedia

NASA Goddard (YouTube Channel)

Parker Solar Probe Mission (NASA)
Parker Solar Probe (JPL, NASA)

Living With a Star Program (NASA)
The Sun (NASA)

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

Learning to Capture the Sun (National Air and Space Museum)
Sun (National Air and Space Museum)

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 (Encyclopædia Britannica)

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


Library of Congress # QB520 Sun (UPenn Online Books)

WorldCat, Library of Congress, UPenn Online Books, Open Library




Why does the sun burn us? (Space Place, NASA)
Sun (Cosmos4Kids)

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



Sun (Science@NASA)
Sun (Astronomy Magazine)
Sun (Science Daily)
Sun (
Sun (NPR Archives)


Space Weather Prediction Center (NOAA)


Sun (



Here Come Science (They Might be Giants, YouTube Playlist)
They Might Be Giants (Official Site)
They Might Be Giants (Wikipedia)


Sun (Tim Hunkin, The Rudiments of Wisdom Encyclopedia)


OEDILF: The Omnificent English Dictionary In Limerick Form


The Chromatics: Full Spectrum A Cappella




Explore related posts on Cosma


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.