Sun

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Sun
The sun is the largest celestial body in our
solar system. The average distance of the sun
from the Earth is 149,597,870 kilometers. Its
radius is about 432,5000 miles. In other words it
is about 109.3 times more than earth's. The Sunís
volume is about 1.3 million times the volume of
the Earth. Also, the mass of the Sun is about
333,4000 times greater than the mass of earth.
The Sun is also a very bright star. The Surface
temperature of the sun is about 10,000 F. The
intense heat of the sunrays can destroy the
retinal cells, which causes blindness.
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Sun
The sun is the largest celestial body in the
solar system. The sun has many gods that
represent it there is the Roman god, Apollo,
Helios (is another name for Apollo) and the
Egyptian god, Ra. Apollo was the twin of Artemis
(Greek) or Diana (Roman) and the son of Jupiter.
His symbol represents the egg of creation. Apollo
had many talents especially for music. One myth
states Mercury had stolen Apollo's cows, so in
return, Mercury traded Apollo his lyre. He later
traded Mercury a musical pipe for a staff. He has
a throne on Olympus, which is the home of the
gods. The sun in astrology represents the force
of life it focuses on you, what you are and what
you do. The Laurel tree, the dolphin, crow and
many other animals are sacred to Apollo.
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Sun
Sun Facts Sheet Mass 1.989 x 1030 kg Mean
density 1410 kg/m3 (about 25 of the earth
density Interior about 70 hydrogen and 28
helium by mass everything else ("metals") amounts
to less than 2. Core Temp 15.6 million Kelvin
Atmosphere photosphere, is at a temperature of
about 5800 K A small region known as the
chromosphere lies above the photosphere the
corona, extends millions of kilometers into space
but is visible only during a total solar eclipse
(left). Temperatures in the corona are over
1,000,000 K
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diameter 1,390,000 km. mass 1.989e30 kg
temperature 5800 K (surface) 15,600,000 K (core)
The Sun is, at present, about 70 hydrogen and
28 helium by mass everything else ("metals")
amounts to less than 2. This changes slowly over
time as the Sun converts hydrogen to helium in
its core.
The outer layers of the Sun exhibit differential
rotation at the equator the surface rotates once
every 25.4 days near the poles it's as much as
36 days. This odd behavior is due to the fact
that the Sun is not a solid body like the Earth.
Similar effects are seen in the gas planets. The
differential rotation extends considerably down
into the interior of the Sun but the core of the
Sun rotates as a solid body. Conditions at the
Sun's core (approximately the inner 25 of its
radius) are extreme. The temperature is 15.6
million Kelvin and the pressure is 250 billion
atmospheres. At the center of the core the Sun's
density is more than 150 times that of water.
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The Sun's energy output (3.86e33 ergs/second or
386 billion billion megawatts) is produced by
nuclear fusion reactions. Each second about
700,000,000 tons of hydrogen are converted to
about 695,000,000 tons of helium and 5,000,000
tons (3.86e33 ergs) of energy in the form of
gamma rays. As it travels out toward the surface,
the energy is continuously absorbed and
re-emitted at lower and lower temperatures so
that by the time it reaches the surface, it is
primarily visible light. For the last 20 of the
way to the surface the energy is carried more by
convection than by radiation. The surface of
the Sun, called the photosphere, is at a
temperature of about 5800 K. Sunspots are "cool"
regions, only 3800 K (they look dark only by
comparison with the surrounding regions).
Sunspots can be very large, as much as 50,000 km
in diameter. Sunspots are caused by complicated
and not very well understood interactions with
the Sun's magnetic field. A small region known
as the chromosphere lies above the photosphere.
The highly rarefied region above the
chromosphere, called the corona, extends millions
of kilometers into space but is visible only
during a total solar eclipse (left). Temperatures
in the corona are over 1,000,000 K.
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Atmosphere
The visible solar atmosphere consists of three
regions the photosphere, the chromosphere, and
the solar corona. Most of the visible (white)
light comes from the photosphere, this is the
part of the Sun we actually see. The chromosphere
and corona also emit white light, and can be seen
when the light from the photosphere is blocked
out, as occurs in a solar eclipse. The sun emits
electromagnetic radiation at many other
wavelengths as well. Different types of radiation
(such as radio, ultraviolet, X-rays, and gamma
rays) originate from different parts of the sun.
Scientists use special instruments to detect this
radiation and study different parts of the solar
atmosphere. The solar atmosphere is so hot that
the gas is primarily in a plasma state electrons
are no longer bound to atomic nuclei, and the gas
is made up of charged particles (mostly protons
and electrons). In this charged state, the solar
atmosphere is greatly influenced by the strong
solar magnetic fields that thread through it.
These magnetic fields, and the outer solar
atmosphere (the corona) extend out into
interplanetary space as part of the solar wind.
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Interior
To understand how our Sun works, it helps to
imagine that the interior of the Sun is made up
of different layers, one inside the other. The
innermost layer, the solar core, is the region
where the energy of the Sun is produced. This
energy travels through the next layer of the
solar interior, called the radiation zone, and
eventually reaches the convection zone, where
energy is transferred mainly by the overturning
of solar gases. This convection produces an
everchanging pattern of cells on the surface of
the sun. Direct observations inside the Sun are
not possible, however some diagnostics exist that
allow us to study the Sun's interior.
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Structure Core (200,000 km, 15,000,000
K) Radiation Zone (200,000 500,000 km,
7,000,000 K) Convection Zone (500,000 700,000
km, 2,000,000 K) Photosphere (700,000 700,500
km, 5800 K) Chromosphere (700,500 702,000 km,
4500 K) Transition zone (702,000 710,500 km,
8000 K) Corona
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Sun
Luminosity the rate at which energy is
generated by the surface of the sun. Power the
rate at which energy is generated or consumed. P
Energy/time MKS units J/sec which is called
a Watt (W) The luminosity of the sun is about 4
x 1026 W
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Sun Nuclear Physics
Solar data Note Solar constant is defined to
be the power per square meter received at the
surface of the earth 1400 W/m2