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Our solar system is a very complex place. In this paper I will identify the origin of the
solar system, laws governing the solar system, the sun, the planets and the other bodies
that are included. Our solar system is a collection consisting of the Sun and the bodies
orbiting around it. Included in our dynamic system are nine major planets, numerous
asteroids, at least 68 satellites, and the cosmic interplanetary medium. The inner solar
system consists of the Sun, Mercury, Venus, Earth and Mars. The outer solar system
contains Pluto, Neptune, Uranus, Saturn and Jupiter. "The largest part of the mass of our
solar system (other than that constituting its central star) and almost all of its angular
momentum is stored in four planets- Jupiter, Saturn, Uranus and Neptune." (Kapal, p.6)
The planets, most of the satellites of the planets and the asteroids revolve around the Sun
in the same direction, in nearly circular orbits. When looking down from above the Sun's
north pole, the planets orbit in a counter-clockwise direction. The planets orbit the Sun in
or near the same plane, called the ecliptic. The axis of rotation for most of the planets is
nearly perpendicular to the ecliptic. The exceptions are Uranus and Pluto, which are
tipped on their sides.
Five billion years ago a cloud of hot swirling dust and hydrogen gas gave birth to our Sun
and planets. As the cloud spun and collapsed inwards it flattened into a central mass with
a surrounding disk. Dust and gases in the disk created small condensations each spinning
about its own center. Gravitation condensed and heated the central mass. Density
increased considerably and nuclear fusion began. Energy was released and our Sun flared
into existence. The solar wind of the newly ignited Sun blew away leftover dust and gas
in the vicinity of the inner condensations, leaving the rocky inner planets: Mercury,
Venus, Earth and Mars. In the outer regions of the disk, the solar wind was weaker. The
left over gas and dust reduced into the larger gaseous planets: Jupiter, Saturn, Uranus and
Neptune.
The Sun and all the planets and their satellites formed through condensation in an
interstellar cloud of gas and dust. The Horsehead Nebula in Orion consists of dust-laden
material. Deep within the clouds of gas and dust, new stars are forming now, some maybe
with planets. As the cloud of gas and dust that formed the solar system began to contract,
it must have got rotation somehow, which led to faster rotation as the cloud shrank. This
rotation tended to maintain the cloud against contraction in directions perpendicular to
the axis of rotation, and thus led to a pancake-like shape for the contracted, rotating
cloud.
When the cloud that would form the solar system first began to contract, it must have
done so as a condensation with some rotation. The rotation was slow at first but grew
more rapid as the cloud shrank. The combined result of the contraction and rotation was a
spinning, disk-like solar nebula, within which gas and dust had much greater density than
they did before the contraction began. The nebula was densest of all at its center, where
the proto-sun began its final condensation. By the time the sun grew so dense that nuclear
fusion reactions began inside it, the pancake-shaped cloud had begun to form
agglomeration at various distances from its center. The rather regular spacing of the
planets' orbits from the sun apparently reflects the way in which matter accumulated
within the disc-like configuration.
The nine planets orbit the sun in nearly circular trajectories that all (except for Mercury
and Pluto) lie in very nearly the same plane. The Sun contains 99.9 percent of the mass in
the solar system, and the four giant planets have the bulk of the 0.1 percent residue. The
Earth, largest of the four inner planets, has only 1/318 of Jupiter's mass and 1/329,000 of
the sun's mass. The four giant planets differ most strikingly from the four inner planets
(Mercury, Venus, Earth, and Mars) in their size and composition. The giant planets are
large, gaseous, rarefied, and hydrogen-rich, while the inner planets are small rocky,
dense, and hydrogen-poor. Because the giant planets consist mostly of hydrogen and
helium, they resemble the universe at large. The inner planets are distinctly different:
Though the universe consists mostly of hydrogen, the Earth does not.
A relatively simple explanation exists for the extreme differences between the four giant
planets and the four inner planets. As nuclear-fusion reactions began in the sun's deep
interior 4.5 billion years ago, the solar nebula close to the sun grew much warmer than
the dust and gas at greater distances. This warming had a profound effect on the kinds of
material that could condense and accumulate into "planetesimals," the small objects that
can collide to form planets. At distances close to the sun - less than about five times the
Earth-sun distance (5 astronomical units, or A.U.) - the sun's heat prevented ice from
forming. This fact had significant consequences, since ice is potentially the most
abundant solid in the universe
There are also rules in our solar system. Before explaining some of the laws governing
the solar system, here are the basic rules. The planets orbits deviate, but little from
circles. The plane of such orbits cluster around the invariable plane of the system,
through inclination to the solar equator is considerable. Lastly, the celestial bodies
revolving in such orbits do so in the same direction. In explaining our dynamic space,
people have come up with laws to explain this "phenomenon". For example, in Keplers
Laws: The mass of all planets is low compared to the sun. The path of a comet, asteroid
or planet is controlled only by the gravitational force of the sun, which is inversely
proportional to the square of the heliocentric distance, in accordance with Newtons Law
of Universal Attraction. For the motion of the planets there are three Empirical Laws.
"1. The orbit of a planet is an ellipse, with the centre of the Sun at one of the foci. The
movement of the object may be described as follows:
r = a [(1-e^2 ) / (1+e cos 0)]
Where r - heliocentric distance, a - semi-major axis of the ellipse, e - eccentricity, and
0 - angle, measured in radians.
2. The radius vector joining the centre of the Sun to the planets sweeps out equal areas in
equal periods of time. This law of areas, which expressed as:
(dA / dt) = (1 / 2) [(r^2) (d0 / dt)] = (h / 2)
Where A - is the area swept out by the sun-planet radius, h - area constant
3. The ration of the cube of the semi-major axis to the square of the period is the same for
all planets:
a^3 / P^2 = 1
Where P - is orbital period in years, and a - semi-major axis, in Astronomical Units
(Encrenaz, p.10)
The Sun is a star of intermediate luminosity and size. Sunlight and other radiation are
produced by the conversion of hydrogen into helium in the Sun's hot, dense interior. The
Sun is so massive that it can continue to shine at its present brightness for six billion
more years.
The Sun is the richest source of electromagnetic energy in the solar system. It is because
of its light and heat given off. The Sun's nearest known astral neighbor is Proxima
Centauri, a red dwarf star that is about 4.3 light years away. The whole solar system,
together with the local stars visible on a clear night, orbits the center of our home galaxy,
a spiral disk of two hundred billion stars we call the Milky Way.
As mentioned before the Sun contains more than ninety-nine percent of the mass of the
solar system, and the Sun lies at the center of the system. Solid grains of such debris, the
space through which the planets travel contains protons, electrons, and ions of the
abundant elements, are all streaming outward from the Sun in the form of the solar wind.
Occasional giant flares on the Sun's surface expel matter, along with high-energy
radiations, that contribute to this interplanetary medium.
Mercury is the closest planet to the Sun, and second smallest planet in the solar system. It
moves quickly across our sky. Its diameter is 40% smaller than Earths. It is even smaller
than Jupiter's moon Ganymede. Mercury's dust-covered hills have been eroded because
meteoroids are constantly hitting it. Fault-cliffs rise for several kilometers in height and
extend for hundreds of kilometers. Craters dot the surface. Although Mercury is not
tidally locked to the Sun, its rotational period is tidally coupled to its orbital period.
Mercury rotates one and a half times during each orbit. A day on Mercury is 176 Earth
days long. Plains cover most of Mercury's surface. The smooth plains are younger still
with fewer craters. Smooth plains can be found around the Caloris basin. Mercury does
not have any moons or rings.
Venus is the second planet, being .72 AU from the Sun. It is also the sixth largest. Venus'
orbit is the most nearly circular of that of any planet, with an eccentricity of less than 1%.
Its diameter is 12,103.6 kilometers and its mass is 4.869 kilograms. Venus' rotation is
somewhat unusual in that it is both very slow and retrograde. Also, the periods of Venus'
rotation and of its orbit are synchronized such that it always presents the same face
toward Earth when the two planets are at their closest approach. Sometimes Venus is
called Earth's sister planet. The pressure of Venus' atmosphere at the surface is 90
atmospheres. It is composed mostly of carbon dioxide. There are several layers of clouds
many kilometers thick composed of sulfuric acid. These clouds completely obscure our
view surface. This dense atmosphere produces a run-away greenhouse effect that raises
Venus' surface temperature is hot enough to melt lead. The interior of Venus is probably
very similar to that of Earth: an iron core about 3000 km in radius, a molten rocky mantle
comprising the majority of the planet. Like our planet, convection in the mantle produces
stress on the surface that is relieved in many relatively small regions instead of being
mainly at plate boundaries, as is the case on Earth. Also like Mercury, Venus does not
have any rings or moons.
There is not too much to talk about our planet, since we all live here, and we know what
it is like here. Earth is the fifth largest planet and the third from the sun, at a distance of
149,600,000 kilometers. Its mass is 5.9736e24 kilograms. Also, its diameter is 12,756.3
kilometers. The name derives from Old English and German. It was not until the 16th
century that we realized that the Earth is just another planet.
Mars, Earth's neighbor, is the fourth planet from the Sun. Mars' bright appearance and
reddish color stand out in the night sky. It has impressive surface features such as valleys
that are frequently obscured by huge dust storms and volcanoes. The uniquely red surface
of Mars has many features - some like those on the Earth and others strangely different.
The rust in the soil causes its reddish color. Some of these features are volcanoes, canyon
systems, riverbeds, cratered terrain, and dune fields. Of these features, the most
interesting include the dead volcano named Olympus Mons and Valles Marineris.
Olympus Mons rises very high above the surrounding plains and is the highest known
mountain in the Solar System. Valles Marineris is a giant canyon. The atmosphere of
Mars is much thinner than that of Earth. Surface temperatures range from -113oC at the
winter pole to 0oC on the dayside during summer. A day on Mars is 24 hours and 37
minutes. Mars' atmosphere is composed mainly of carbon dioxide. Oxygen makes up
only 0.13% of the atmosphere at Mars. There is only one-fourth as much water vapor in
the atmosphere. This planet is thought to have frozen ice at its poles. It has two moons;
Phobos and Deimos.
Jupiter, the fifth planet from the Sun, has the most powerful winds and storms, but also
the most majestic cloud patterns. It is the largest planet in our dynamic solar system.
Jupiter is made of the simple molecules hydrogen and helium, and they become liquid in
the environment that is found deep inside Jupiter. The atmosphere of Jupiter is only a
narrow layer, compared to Jupiter's vast insides. The clouds of Jupiter are at different
levels in the atmosphere. Motions inside Jupiter help form the powerful magnetosphere
of Jupiter. Heat from within Jupiter contributes to the unusual movements of the
atmosphere. Jupiter looks very colorful because molecules such as sulfur. Jupiter's
magnetosphere is the biggest is the solar system. Jupiter has a donut-shaped cloud, which
goes around inside the magnetosphere. Its called the Great Red Spot, which is similar to
Neptune's'. Jupiter also makes radio signals. Jupiter has 17 moons and a ring system. The
four moons Io, Europa, Ganymede, and Callisto, are the most fascinating. Io has
volcanoes, and Europa may have a water environment where life might be found.
Jupiter's small moons are Metis Adrastea, Amalthea, Thebe, Leda, Himalia, Lysithea,
Elara, Ananke, Carme, Pasiphae, Sinope and S/1999 J1.
The sixth planet from the sun is Saturn. Saturn has 22 moons and huge rings that you can
see in a picture of Saturn. The moon Titan is one of the only moons in the entire solar
system with air. Mimas is one of Saturn's moons, shaped like the "Death Star". One of
Saturn's moons is half-dark and half-bright. That one is called Iapetus. Saturn is
composed of simple molecules hydrogen and helium, and they become liquid in the
environment that is found deep inside Saturn. Heat from inside Saturn contributes to the
unusual movements of the atmosphere. The clouds of Saturn aren't as colorful as those of
Jupiter. Saturn's atmosphere is composed of more sulfur. Sulfur makes Saturn look
yellow. The atmosphere of Saturn is only a narrow region, compared to Saturn's huge
insides. The clouds of Saturn are to be found mostly low in the atmosphere. Smog can be
found higher up. Saturn has very powerful winds. The rings of Saturn affect the motion
of particles in the magnetosphere. Saturn's magnetosphere produces beautiful auroras.
Also it produces radio waves.
Uranus, the seventh planet from the Sun, is made of ice. The plain blue green face of
Uranus shows that Uranus is made of only one thing. Heat from inside Uranus helps it to
make unusual winds in the atmosphere. Although Uranus' atmosphere is still forming, is
has clouds and smog. Motions in the cloud patterns indicate that, like Jupiter and Saturn,
the winds of Uranus move in a striped pattern. Daytime on Uranus lasts for the whole
summer and it is a sideways planet. The magnetosphere of Uranus has a very strange tilt.
The extreme tilt, combined with the extreme tilt of Uranus itself, makes for a completely
strange magnetosphere. Uranus has 21 interesting moons and a ring system. At Uranus
there is even a half ring, or "ring arc". The moons are Cordelia, Ophelia, Bianca,
Cressida, Oberon, 1986 U 10, Caliban, Sycorax, Desdemona, Juliet, Portia, Rosalind,
Belinda, Puck, Miranda, Ariel, Umbriel, Titania, Prospero, Setebos, and Stephano.
The eight planet, Neptune's interior is mostly methane ice. Heat generated inside Neptune
aids in the occurrence of unusual winds in the atmosphere. The composition of Neptune
clouds is thought to be methane molecules. Neptune's atmosphere shows a striped pattern
of clouds. This cloud pattern is close to Jupiter's' and Saturn's'. Neptune has a Great Dark
Spot similar to Jupiter's Great Red Spot. Neptune has a medium magnetosphere. Neptune
has several moons and a complicated ring system. The ring system is a totally different
type of ring system than Uranus' or Saturn's'. Neptune has eight moons. Neptune's major
moon is called Triton. It is thought to have active geysers. Triton might also have a water
environment like the one at our north pole. Life may exist there. This icy moon may have
a thin atmosphere and an active interior. Other moons are Despina, Galatea, Larissa,
Naiad, Proteus, Thalassa and Nereid.
The ninth planet, Pluto shows remarkable dark markings very much like Saturn's moon
Iapetus. Pluto is probably also made of ice, similar to the other icy moons, however not
ice made of water, but ice made of frozen nitrogen. Winds of Pluto's atmosphere may
sweep the ices away and leave dark markings on the surface. The interior of Pluto is
probably similar to that of major icy moons such as Ganymede. The evolution of the
double planet Pluto and Charon may be like only one other planet in the solar system,
that of the Earth and its moon. Sometimes there are times when Pluto is closer to the sun
than is Neptune, making it the 8th planet for roughly 20 years at a time. During that time
ice on Pluto's surface evaporate and form an atmosphere. The air is made mostly of
nitrogen gas. It is also possible that the presence of nearby moon, Charon draws
molecules to it, which is escaping from Pluto's atmosphere. Pluto may well have a
magnetic field, being warmed by tidal forces stemming from its dual orbit with its moon
Pluto's moon, Charon, is 12,200 miles from the planet and has a diameter of 1,200
kilometers. Charon was first seen from Earth in 1978. Pluto and Charon are almost the
same size, and they act like a double planet.
Comets are lumps of ice and rock that randomly come into the center of the solar system
from somewhere, and some comets make several trips. The nucleus of comets can be
oddly shaped and can be only a few miles across. When comets get close enough to the
Sun, heat makes the nucleus start to evaporate. A cloud of gas and dust called the coma
forms. The coma can reach a similar diameter to that of a giant planet! Jets of gas and
dust form long tails that we can see from Earth.
Asteroids are small bodies that are believed to be left over from the beginning of the solar
system 4.6 billion years ago. They are rocky objects with round or irregular shapes up to
several hundred km across, but most are much smaller. More than 100,000 asteroids lie in
a belt between Mars and Jupiter. These asteroids lie in a location in the solar system
where there seems to be a jump in the spacing between the planets. Some think that this
debris may be the remains of an early planet, which broke up early in the solar system.
Several thousand of the largest asteroids in this belt have been given names. Asteroids
can be a few feet to several hundred miles wide. The belt probably contains at least
40,000 asteroids that are more than 0.5 miles across.
The Kuiper Belt is a disk-shaped region past the orbit of Neptune roughly 30 to 100 AU
from the Sun containing many small icy bodies. It is the source of the short-period
comets. Sometimes the orbit of a Kuiper Belt object will be disturbed by the interactions
of the giant planets in such a way as to cause the object to cross the orbit of Neptune. It
is estimated that there are at least 35,000 Kuiper Belt objects greater than 100 km in
diameter, which is several hundred times the number of similar sized objects in the main
asteroid belt.
Exactly where the boundary between the interstellar medium and the interplanetary
medium lies has not yet been determined, but four spacecraft have recently passed the
orbit of Pluto with velocities that will allow them to escape from the solar system. Thus,
this boundary may be crossed in the near future.
Works Cited
Britannica Online Site. 4 Nov. 2000
http://www.britannica.com/bcom/eb/article/2/0,5716,118792+2+1101143,00.html
Encarta Msn Site. 2 Oct 2000
http://Encarta.msn.com/find/Concise.asp?z=1"pg=2"ti=01831000
Nine Planets Site. 2 Oct 2000
http://lpl.arizona.edu/nineplanets.html
Encrenaz, Therese. The Solar System. Berlin, New York:
Springer-Verlag, 1990.
Kopal, Zdrenek. The Solar System. London, New York:
Oxford University Press, 1972.
Nourse, Alan Edward. Nine Planets. New York:
Harper, 1960.
Keywords:
solar system very complex place this paper will identify origin solar system laws
governing solar system planets other bodies that included collection consisting bodies
orbiting around included dynamic nine major planets numerous asteroids least satellites
cosmic interplanetary medium inner consists mercury venus earth mars outer contains
pluto neptune uranus saturn jupiter largest part mass other than that constituting central
star almost angular momentum stored four planets jupiter saturn uranus neptune kapal
most satellites asteroids revolve around same direction nearly circular orbits when
looking down from above north pole orbit counter clockwise direction orbit near same
plane called ecliptic axis rotation most nearly perpendicular ecliptic exceptions uranus
pluto which tipped their sides five billion years cloud swirling dust hydrogen gave birth
cloud spun collapsed inwards flattened into central mass with surrounding disk dust gases
disk created small condensations each spinning about center gravitation condensed heated
central mass density increased considerably nuclear fusion began energy released flared
into existence wind newly ignited blew away leftover dust vicinity inner condensations
leaving rocky inner mercury venus earth mars outer regions disk wind weaker left over
reduced into larger gaseous jupiter saturn neptune their satellites formed through
condensation interstellar cloud horsehead nebula orion consists laden material deep
within clouds stars forming some maybe with that formed began contract must have
rotation somehow which faster rotation shrank this tended maintain against contraction
directions perpendicular axis thus pancake like shape contracted rotating when would
form first began contract must have done condensation with some slow first grew more
rapid shrank combined result contraction spinning like nebula within which much greater
density than they before contraction nebula densest center where proto final condensation
time grew dense nuclear fusion reactions inside pancake shaped begun form
agglomeration various distances from center rather regular spacing orbits from apparently
reflects matter accumulated within disc like configuration nine orbit nearly circular
trajectories except mercury pluto very same plane contains percent four giant have bulk
percent residue earth largest four only giant differ most strikingly venus mars their size
composition giant large gaseous rarefied hydrogen rich while small rocky dense
hydrogen poor because consist mostly helium they resemble universe large distinctly
different though universe consists mostly does relatively simple explanation exists
extreme differences between nuclear fusion reactions deep interior billion years close
grew much warmer than greater distances this warming profound effect kinds material
could condense accumulate planetesimals small objects collide form distances close less
about five times distance astronomical units heat prevented forming fact significant
consequences since potentially abundant solid universe there also rules before explaining
some laws governing here basic rules orbits deviate little circles plane such cluster
around invariable through inclination equator considerable lastly celestial bodies
revolving such direction explaining dynamic space people come laws explain
phenomenon example keplers compared path comet asteroid planet controlled only
gravitational force inversely proportional square heliocentric distance accordance
newtons universal attraction motion there three empirical planet ellipse centre foci
movement object described follows where heliocentric distance semi major axis ellipse
eccentricity angle measured radians radius vector joining centre sweeps equal areas equal
periods time areas expressed where area swept planet radius area constant ration cube
semi major square period orbital period years semi astronomical units encrenaz star
intermediate luminosity size sunlight other radiation produced conversion helium dense
interior massive continue shine present brightness billion more richest source
electromagnetic energy because light heat given nearest known astral neighbor proxima
centauri dwarf star about light away whole together local stars visible clear night home
galaxy spiral hundred stars call milky mentioned before contains more ninety nine
percent lies solid grains such debris space through travel protons electrons ions abundant
elements streaming outward wind occasional flares surface expel matter along high
energy radiations contribute interplanetary medium closest second smallest moves
quickly across diameter smaller earths even smaller moon ganymede covered hills been
eroded because meteoroids constantly hitting fault cliffs rise several kilometers height
extend hundreds kilometers craters surface although tidally locked rotational period
tidally coupled orbital rotates half times during each days long plains cover surface
smooth plains younger still fewer craters smooth plains found caloris basin does moons
rings second being also sixth largest circular eccentricity less diameter kilometers
kilograms somewhat unusual both very slow retrograde also periods synchronized always
presents face toward when closest approach sometimes called sister pressure atmosphere
atmospheres composed mostly carbon dioxide there several layers clouds many thick
composed sulfuric acid these clouds completely obscure view atmosphere produces away
greenhouse effect raises temperature enough melt lead interior probably similar iron core
radius molten rocky mantle comprising majority convection mantle produces stress
relieved many relatively regions instead being mainly plate boundaries case does rings
moons much talk since live here know what here fifth third kilograms diameter name
derives english german until century realized just another neighbor fourth bright
appearance reddish color stand night impressive features valleys frequently obscured
huge storms volcanoes uniquely many features those others strangely different rust soil
causes reddish color these features volcanoes canyon systems riverbeds cratered terrain
dune fields these interesting include dead volcano named olympus mons valles marineris
olympus mons rises high above surrounding highest known mountain valles marineris
canyon atmosphere thinner temperatures range winter pole dayside during summer hours
minutes composed mainly carbon dioxide oxygen makes only fourth water vapor thought
frozen poles moons phobos deimos fifth powerful winds storms majestic patterns
dynamic made simple molecules helium they become liquid environment found deep
inside narrow layer compared vast insides different levels motions inside help powerful
magnetosphere heat contributes unusual movements looks colorful molecules sulfur
magnetosphere biggest donut shaped goes magnetosphere called great spot similar makes
radio signals ring europa ganymede callisto fascinating volcanoes europa water
environment life might found metis adrastea amalthea thebe leda himalia lysithea elara
ananke carme pasiphae sinope sixth huge rings picture moon titan entire mimas shaped
death half dark half bright iapetus simple molecules become liquid environment
contributes unusual movements aren colorful those sulfur sulfur makes look yellow
narrow region compared huge insides smog higher powerful winds affect motion
particles produces beautiful auroras radio waves seventh made plain blue green face
shows made thing helps make winds although still forming smog motions patterns
indicate move striped pattern daytime lasts whole summer sideways strange tilt extreme
tilt combined extreme tilt itself completely strange interesting ring even ring cordelia
ophelia bianca cressida oberon caliban sycorax desdemona juliet portia rosalind belinda
puck miranda ariel umbriel titania prospero setebos stephano eight methane generated
aids occurrence composition thought methane shows striped pattern pattern close great
dark spot similar great spot medium several complicated totally type eight moon triton
thought active geysers triton might water north pole life exist thin active despina galatea
larissa naiad proteus thalassa nereid ninth shows remarkable dark markings iapetus
probably however frozen nitrogen sweep ices leave markings probably ganymede
evolution double charon sometimes times closer making roughly time during evaporate
nitrogen possible presence nearby charon draws escaping well magnetic field being
warmed tidal forces stemming dual charon miles first seen almost size double comets
lumps rock randomly come somewhere comets make trips nucleus comets oddly miles
across enough nucleus start evaporate coma forms coma reach jets long tails asteroids
believed left over beginning objects round irregular shapes hundred across smaller belt
between location seems jump spacing between think debris remains early broke early
thousand belt been given names feet hundred miles wide belt least kuiper region past
roughly containing source short sometimes kuiper object will disturbed interactions cause
object cross estimated least kuiper objects greater number sized main asteroid exactly
boundary interstellar interplanetary lies been determined spacecraft recently passed
velocities will allow them escape thus boundary crossed near future works cited
britannica online site http britannica bcom article html encarta site http encarta find
concise site http arizona nineplanets html encrenaz therese berlin york springer verlag
kopal zdrenek london york oxford university press nourse alan edward york harper
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