Home (Sun)


  » »


Astronomy  Summer Solstice  Sundial

Our Sun has inspired mythology in almost all cultures, including ancient Egyptians, Aztecs, Native Americans, and Chinese. We now know that the Sun is a huge, bright sphere of mostly ionized gas, about 4.

Sun, star around which Earth and the other components of the solar system revolve. It is the dominant body of the system, constituting more than 99 percent of its entire mass.

Sun-Earth Day is a celebration established in 2000 by NASA and ESA. The purpose of the holiday is to popularize the knowledge about the Sun, and the way it influences life on the Earth.
[edit] See also ...

Sun, the solar system's only star
Stars are born. They take shape. They go through a turbulent adolescence, and then they live out their lives in a predictable pattern. Some have companions to provide for.

Related Category: Astronomy: General
intensely hot, self-luminous body of gases at the center of the solar system. Its gravitational attraction maintains the planets, comets, and other bodies of the solar system in their orbits.

The closest star to the Earth and the center of the solar system.
Resources ...

Sun and planets formed from different ingredients
Posted: 28 June 2011 ...

sun at HighBeam Research
sun on Wikipedia
sun. Wikimedia Commons (Public Domain) ...

The Sun in Mythology
Creation is often linked to a combination of the Sun (Male) and Moon (Goddess) - representing duality in physical reality.

The Sun
The Sun, among other things, is the brightest star in the sky. Its irradiance is so high that it's not safe to observe it with naked eyes or an instrument without a proper solar filter. This is very important! Failure… ...

sun spot - Space and Astronomy Definition - Online Dictionary and Glossary ...
high sun - Space and Astronomy Definition - Online Dictionary and Glossary ...
Cepheid Variable - Space and Astronomy Definition - Online Dictionary and G...

Mankind will not remain on Earth forever, but in its quest for light and space will at first timidly penetrate beyond the confines of the atmosphere, and later will conquer for itself all the space near the Sun. - Konstantin E. Tsiolkovsky ...

Sun Information
Enchanted Learning Search
First search engine with spelling correction and pictures! ...

A Sun-synchronous orbit is an interesting orbit. Since the Earth is not an exact sphere (it has a slight bulge at the equator) satellite orbits can be effected by the extra gravitational pull.

The sun's atmosphere consists of the chromosphere, corona, and photosphere. The photosphere is the bright visible surface of the sun, with a surface temperature of 5,800 K.

The Sun
"The sun is only a star / around that star we spin" goes the words of a song "Child of the Universe." The sun is only a star, and an average one at that. It is unimportant in the grand scheme of the universe.

The Sun in the He II emission line.
The Sun is the Earth's dominant source light (and thus heat) and the star about which all of the planets of the solar system orbit. The Sun has mass 1.

The Sun is a star at the center of our solar system. Our Sun is a medium-sized yellow star that is 93,026,700 miles (149,680,000 km) from Earth. Its diameter is 865,121 miles (1,391,980 km).

The sun is a huge, spinning ball of hot gas that glows in the sky. Our sun is a medium sized star. It looks larger and brighter than the other stars because it the nearest star to Earth. It is about 150 million kilometres away.

Our Sun is gorgeous, and dangerous, and amazing. These pictures and videos are more than just beautiful; they are telling us about the mechanisms and processes occurring both on the surface and inside our nearest star.

Wikipedia, the free encyclopedia - Cite This Source
The Sun (Sol) is the star at the center of the Solar System.

Sun Watching Satellite SOHO Regains Ability
Solar and Heliospheric Observatory (SOHO), the Sun-watching satellite, ...

Sun City Palm Desert Astronomy Club
Please contact this organization for information on their astronomy viewing schedules, telescope availability, membership, and public programs.
Sun City Palm Desert Astronomy Club ...

"Sun Observer's Guide" by Pam Spence,159 pp., Firefly Books, 2004. A concise and readable overview. Questions from Users: The color and temperature of stars and of the Sun
*** Questions about the Solar Corona: ...

The Sun's Surface
The deepest layer of the Sun you can see is the photosphere. The word ``photosphere'' means ``light sphere''. It is called the ``surface'' of the Sun because at the top of it, the photons are finally able to escape to space.

The Sun
Our Sun is a yellow dwarf star. Its official designation is as a G V star. Stars in the this classification have a surface temperatures between 5,300 and 6,000 K and fuse hydrogen into helium to generate their light.

Our Sun's Lost Sibling
By Brian Ventrudo
Like most stars in the Milky Way, our Sun was born in a cluster of hundreds of new stars in a cloud of glowing gas and dust like the Orion Nebula, ...

The Sun
When we think of stars, we usually neglect the fact that the nearest one is right in our own backyard: the Sun! ...

The Sun
Many ancient peoples worshiped the Sun as a god. They thought a solar eclipse meant the god was angry with them. They believed the Sun god's anger could only be calmed with prayer and sacrifice.

The Sun in Time
home page
...is a program designed to integrate science and social studies curricula through a study of Solar Science and Archaeoastronomy.

The Sun
Our Sun is a normal main-sequence G2 star, one of more than 100 billion stars in our galaxy. diameter: 1,390,000 km. mass: 1.989e30 kg temperature: 5800 K (surface) 15,600,000 K (core) ...

The Sun: An Introduction to the Stars
In this course, Astronomy 124, we will be learning about the contents of the universe, from the relatively small scales of a single star system up to the largest distances known, ...

Sun spots come and go on a regular basis. At times there are very few if any sun spots. Other times there are far more. They generally increase in intensity and then decrease over a period of 11 years. This 11 year cycle is known as the Saros Cycle.

The star at the center of our solar system. An average star in terms of size and mass, the Sun is a yellow dwarf of spectral type G2.

Sun Headlines
things you should know about your hamster's cage
Everyone has a dead bird story ...

THE SUN. Similar in many languages, "Sun," related to Latin's "sol," was represented in ancient Greece as Helios, god of the Sun.

The Sun. Courtesy of SOHO (ESA & NASA)The Sun is steadily converting the hydrogen in its core into helium. As the available fuel runs out the energy output declines. Outward pressure declines too and so the core of the Sun shrinks.

The Sun is one of the only two objects which can be seen year round by people around the world. The other is, of course, the Moon. The Sun is, however, the only object in the sky which can be dangerous to view.

The Sun and its entourage of planets travel in the general direction of Vega (away from Sirius), orbiting the center of the Milky Way at some 140 to 150 miles per second.

The Sun at wavelengths from x-ray to radio.
Views of the Solar System
Bill Arnett's Solar Tour
Space Weather
A solar virtual tour.
An excellent pictorial introduction to the sun.
Solar Heliospheric Observatory (SOHO).

The Sun also has an influence on the tides, but since it is further away, it doesn't pull as strongly. However, when both the Moon and the Sun are pulling along the same axis, the tides are highest.

"The sun strings these worlds - the earth, the planets, the atmosphere - to himself on a thread." ...

How did the sun's family of planets and minor bodies originate?
How did the solar system evolve to its current diverse state?
How did life begin and evolve on Earth, and has it evolved elsewhere in the Solar System?

Observing Where the Sun Sets
Grade Level: 3-5
Lesson Time: Less Than 30 Minutes
Body: Sun, Earth
Mission: Earth Science Missions (Earth), Heliophysics Missions (Sun) ...

Set it on a flat surface and rotate the base of the fixture so that the North Pole is farthest away from an imaginary light source (the Sun). This simulates winter in the northern hemisphere; summer in the southern hemisphere.

Thus, in the Copernican model the Sun was at the center, but the planets still executed uniform circular motion about it. As we shall see later, the orbits of the planets are not circles, they are actually ellipses.

Analysis of data from GONG and other sources shows that current theories about the structure of the Sun need to be expanded.

The Sun will appear directly opposite it on the sky, so subtract 12h from the right ascension (or add 12h, as the case may be), and change the sign of the declination. That puts the Sun at 5h 57.

Welcome to the Tour of Our Sun! The following pages will tell you about how scientists are studying our Sun this very minute. There are about eight main pages to this tour with lots of hyperlinks to more technical information.

Sun Sensors
Cassini's Attitude and Articulation Control computers take input from one of two sun sensors, along with input from the stellar reference unit, and the inertial reference unit.

Sun and Planets
The following table compares major features of the Sun and planets, and relates many planetary characteristics to Earth's own:
(AU) ...

Sun redirects here. For information on Earth's sun, see Sol. You may be searching for the actress Star.

Sun Liang was an emperor of Eastern Wu during the Three Kingdoms period. He was the founding emperor Sun Quan's youngest son and heir.

Sun: The Sun is a star and the biggest object in the Solar System, it burns brightly in the center as planets and other objects orbit around it.

Sun: One of the 100 billion stars in our galaxy. 1,390,000 km diameter. Temperature at the core: 15,600,000 K. Temperature at the surface: 5800 K.

Sun: The star associated with Earth's solar system. The Sun weighs about 2x1030 kilograms, and is about 1.4x109 meters in diameter.
Supergiant: Very luminous star 10-1000 time more massive than the Sun.

The star at the centre of our solar system, providing the light and heat required for life on Earth.
A device used to determine the time of day by observing shadows cast by a gnomon.

SUN - Our parent star. The structure of Sun's interior is the result of the hydrostatic equilibrium between gravity and the pressure of the gas. The interior consists of three shells: the core, radiative region, and convective region.

(a) The star that Earth orbits. The Sun is a yellow main-sequence star that is spectral type G2, shines with apparent magnitude -26.74, and has an absolute magnitude of +4.83. The Sun is 4.6 billion years old.

Sun, Mercury, Venus, Earth, Moon, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto, Quaoar, Asteroids, Comets, Sedna ...

The Sun Is Moved To The Center
They explained this by assuming the planets and stars (as well as the Moon and Sun) were fixed on large, concentric, invisible, rotating spheres with the Earth at their center.

The Sun
08.18.09 - Read about Earth's sun, and learn a song, too!
What Is NASA?

What sort of radiation is emitted by a gas of 1,000,000 K?

Mock Sun. An effect caused by ice crystals in Earth's atmosphere which refract sunlight and cause the appearance of two diffuse patches of light 22 either side of the Sun.

and ∴ Sun's diameter = 1,390,000 km (or 1.39 - 109 m).
If a star is 20 parsecs away and has an apparent magnitude of +6, what is its absolute magnitude?

1) Why the Sun and Moon live in the sky Retold and Illustrated by Niki Daly $15.00 (hardcover) African Myth - This book was also found on the shelf of Barnes and Nobles ...

Sun, Moon & Planets - now!
Your browser does not support iframes or is configured not to display them. You may wish to enable iframes in your browser's preferences, if that option is available to you, so that this content may be displayed.

Sun The star at the center of our solar system. It is made mostly of hydrogen and helium with traces of heavier elements. This image of the Sun is courtesy of SOHO/EIT.
More about the Sun...

Sun-centered; using the sun rather than the earth as the point to which we refer. A heliocentric measurement, for example, omits the effect of the Doppler shift caused by the earth's orbital motion.
helium - (n.) ...

A sun like star is dying. It becomes
? a brown dwarf.
? a yellow giant;
? a red super giant
? a red giant.

No sun tan lotion required
Pluto is situated so far out in the depths of the solar system that if you were to stand on its surface the sun would just look like a bright star.
Size matters ...

The Sun shining through the Stonehenge monument. Sun rise on the summer solstice was the most important time the Sun would shine through the monument.
Click on image for full size
Windows to the Universe original image ...

The sun passes this constellation from late July to early August. In former times the Sun used to lie in this constellation when it reaches the its point farthest north - the time of the summer solstice.

The Sun now:
Welcome to Astronomy For Beginners! As I was getting into astronomy I found it difficult trawling through all the virtually infinite amount of information on the internet, ...

The Sun and Earth pass through Saturn's ring plane on August 10th and September 4th, 2009. However, unlike the Saturn ring plane crossing of 1995, the 2009 events will occur when Saturn, viewed from Earth, is close to the sun.

The Sun is in Pisces from March 13 to April 19, and it crosses the ecliptic on March 21, which marks the vernal Equinox, the first day of autumn in the southern hemisphere.

The Sun, a spectral class G2 star that contains 99.86% of system's mass.
The planets of the solar system are those nine bodies traditionally labelled as such; Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.

The Sun is in the galactic disk, about half-way from the galactic center to the outer edge of the disk. All of the stars we see in the sky are part of this disk.

The sun is a star and a strong source of radio emission. Most ordinary stars are expected to emit radio waves since they are thermal sources.

The Sun as seen through my 10-inch Meade Schmidt Cassegrain telescope in Orlando, Florida on 3/14/89. This image was captured on Kodak Ektachrome 100 color slide film with a Thousand Oaks full-aperture glass solar filter.

The Sun and nearby disk stars share a common orbital motion about the galactic center, but in addition each has a small random velocity, reflecting the fact that their orbits are not perfect circles.

Our sun is heading away from Columba as fast as it can go. Columba contains the "solar antapex" which is the opposite of the solar apex, which is the direction the sun is headed. Right now, we seem to be journeying toward the constellation Hercules.

The Sun, or any star for that matter, "shines" or "burns" due to a process of thermonuclear fusion, not due to a chemical reaction like the oxygen-driven fires on Earth.

The Sun is at the center of the universe and everything revolves around that. Was first proposed by Copernicus.
The study of the interior of the sun by the analysis of its modes of vibration.

The Sun's path across the sky. The Moon and the planets follow this path closely, since their orbital planes are nearly aligned with Earth's orbital plane. The ecliptic is tilted 23.5 degrees from the celestial equator.
effective temperature ...

The Sun's disk and the separation from the comet are shown to scale, with north at the top of the image and west to the right. Keep in mind that ISON will be very close to the Sun (1.5 on average, around three times the apparent diameter of the Sun).

Of the Sun.
Solar Nebula
The large cloud of gas from which the Sun and planets were formed 4,600 million years ago.

If the sun were replaced by Betelgeuse, the surface of the star might stretch out beyond the asteroid belt. The planets out to the orbit of Mars would be engulfed by the star.

The sun and moon both exert gravitational pull on the earth. This pull has a definite affect on the earth's rotation, because the earth is not perfectly spherical. The earth bulges at the equator.

On the Sun, an extended H-alpha emission feature of an active region that is seen from the time of emergence of the first magnetic flux until the widely scattered remnant magnetic fields merge with the background.

In the Sun convection is also an important process. Convection becomes important whenever the opacity goes up and the rate of radiative diffusion becomes less. Then heat builds up and the boiling begins.

Does our sun rises from the same direction every morning or not?
We know it rises from the east, but does it really rises exactly at the east?
Can you determine the aproximative trajectory of the sun during the day?

One of the Sun's outer layers, visible for a few minutes as a spectacular halo during during a total eclipse of the Sun.
A reddish-colored layer in the solar atmosphere, just above the photosphere.

Midnight Sun
The Sun when visible at midnight, which happens only in summer north of the Arctic Circle or south of the Antarctic Circle.
Milky Way
Our own galaxy.

On nearing the Sun, a comet may develop two tails. The solar wind of high-speed protons and electrons sweeps cometary ions in a direction away from the Sun, producing a straight plasma or ion tail.

Kepler-20: A Sun-like Star with Three Sub-Neptune Exoplanets and Two Earth-size Candidates
March 17, 2012 GAUTIER Th., CHARBONNEAU D., ROWE J., MARCY G., ISAACSON H., TORRES G. & 38 additional authors
ApJ., 749, 15
paper arxiv ...

active (of the sun; characterized by a high level activity in sunspots and flares and radio emissions)
stargaze (observe the stars)
go down; go under; set (disappear beyond the horizon) ...

The Sun's outer atmosphere, which has a high temperature and a low density.
coronal mass ejection
CME; an event in which billions of tons of gas from the Sun's corona is suddenly blasted into space at high speed.

Examining the Sun:
Although we think of sunlight or starlight as white, ...

See also: See also: Astro, Earth, Planet, Solar, Orbit

Astronomy  Summer Solstice  Sundial

RSS Mobile