Introduction Neptune was discovered on Sept. 23, 1846. Neptune
wasnt actually discovered through a telescope instead it was the
first planet to be predicted by mathematical calculations. The name
Neptune comes from Greek and Roman mythology. Neptune is the roman
God of the sea.
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Introduction Neptune is the eighth and most distant planet from
the sun. Neptune is 17 times Earth's mass and nearly 58 times its
volume. Neptune has a diameter of 49,244 km. Neptune's rotational
period is 0d 16h 6m. Orbital period of Neptune is 165 years.
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Introduction Eccentricity of Neptune is 0.00867797. The density
of Neptune is 1.64 g/cm. The mass of Neptune is 102.4E24 kg.
Neptune is the fourth largest planet according to diameter. Even
though being smaller than Uranus, Neptune has a greater mass.
Distance from the sun 4 503 000 000 km
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Voyage 2 was the only spacecraft to pass Neptune. The mission
launched on August 20, 1977. The mission passed Jupiter, Saturn and
Uranus before arriving at Neptune. Voyage 2 arrived at Neptune on
August 25, 1989. It took the Voyager 12 years to arrive at Neptune.
The flight time to Neptune was reduced from 30 years to 12.
Exploration of the Planet
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The voyage 2 returned with detailed photos and other data on
the planet, its moons, magnetic field and dark rings. Voyager 2's
closest approach to Neptune was on August 25, 1989, the spacecraft
flew southward The spacecraft will continue to study ultraviolet
sources among the stars. The whole of voyager 1 and 2 coasted
approximately $865 million but then NASA budgeted an additional $30
million to fund the Voyager 2 for two years following the Neptune
encounter. Exploration of the Planet
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The air of Neptune is extremely cold, with temperatures of -270
degrees to -380 degrees. The air on Neptune is made of complex
molecules, the same sort of molecules that we see coming out of
cars on earth in the form of smog. The inside of Neptune is very
hot, but the temperature is as high as 10,000 degrees. As for life
on Neptune it is highly unlikely for anything to survive on the
planet Life on Neptune?
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Discovery of Neptune First Planet to be discovered by
mathematics after noticing that Uranus was pulled slightly out of
orbit (John Crouch Adams and Urbain Leverrier) Johann Gottfried
Galle observed Neptune for the first time the using their data
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Theories Neptune has a strange structural make up, much like
Uranus, they are called gas giants in our solar system
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The Core Accretion Theory The core accretion theory suggests,
that our solar system formed after a Supernova The sun was the
first created, from as we know the gravity collapsed material,
creating nuclear fusion Then the other material and dust clumped
together, creating the planets while the solar winds pushed the
lighter elements farther away, this means the closer planets had
the heavier material The solar winds had less effect on the light
elements far from the sun, so this is how Neptune and other gas
giants were formed But the closer planets cycled through their
original atmosphere but Neptune and other gas giants atmosphere
stayed the same This theory wouldnt work, unless there were another
factor, scientists have suggested that Neptune was created in a
closer orbit then when the gaseous disk dissipated Neptune moved to
its present position.
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The Disk Instability Theory This theory excepts the idea of
core accretion for the inner planets but believes the gas giants,
through the accretion theory would take to long, hence the lighter
elements would have migrated away by then The accretion theory has
been suggested that if the accretion theory were true, then the
baby planets would eventually migrate to the sun in a short
timespan This theory suggests that the gas giants were created much
quicker, said to be thousands of years, which would be the quickest
The gas giants were said to have clumps of gas and dust, when the
solar system was just created These clumps quickly grew to large
planets, this planet would be formed much quicker, so by then the
solar winds wouldnt of blown all the light elements away, so the
giant planets could take the light elements, before they were gone
This also means that they reach orbital mass quicker so they wont
go into the sun This is a fairly new theory.
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Moons Neptune has 14 moons in total, they are all named after
Greek sea Gods and sea Nymphs because Neptune is the God of the sea
and he commands the other gods, hence all the moons orbit Neptune.
Neptunes Moons are still being discovered, 2009 Hubble found a new
moon, S/2004 N 1.
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Neptune's Rings Neptunes rings are very faint because they are
made up of dust/rocks There are nine rings in total around Neptune
The laws of motion conclude that the rings should, over time
combine into one ring but they have stayed multiple rings. This
could be because of a moon counteracting the gravitational pull of
Neptune or the many moons gravitational pull.
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Largest Moons The three largest moons for Neptune are: Triton
(the Largest), Proteus (second Largest), and Nereid (third
Largest). The diameter of each are: Triton: 2,704 Km, Proteus: 218
x 208 x 201 Km, and Nereid: 304 Km, the rest of the moons are less
then 159 Km. The orbital period of the largest moons are: Triton:
Synchronous, Proteus: 1.1 earth days, and Nereid: 360.1 earth
days.
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Triton Triton is the largest of Neptunes 14 moons; it is a
frozen moon with nitrogen ice and dust spewing off from Tritons
surface. Triton is the coldest object in our solar system that has
been measured at -235C. Triton was thought to be a dwarf planet,
that Neptune caught in its orbit by either getting hit by it or
having enough force to drag it into Neptunes orbit. They predict
this because it is spinning the opposite way around Neptune then it
should compared to the other planets and their large moons, if it
was created in Neptunes orbit Has a hazy atmosphere of mostly
nitrogen, and a windy surface covered in nitrogen ice. The Orbital
Period around Neptune is approximately 9 Earth days but is also
synchronous. Triton is also slowly spiralling towards Neptune
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Proteus Proteus is very close to Neptune; it orbits just over
the cloud-tops of Neptune. Proteus has been hit with so many
meteors, that the craters on Proteus has gave the moon an irregular
shape
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Nereid Also has an irregular shape, not as bad as Proteus
Nereid is the farthest moon form Neptune at 5,513,400 Km away
Theorized to be a captured asteroid because of highly elliptical
orbit Nereid has the most eccentric orbit in the solar system, The
distance from Nereid to Neptune varies from about 1,300,000
kilometers to over seven times as far, 9,600,000 kilometers
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QUESTION 1.Which is not one of Neptunes largest moons? a.Triton
b.Nereid c.Galatea d.Proteus
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QUESTION 2.How many rings does Neptune have? a.9 rings b.12
rings c.3 rings d.4 rings
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QUESTION 3.How many moons does Neptune have? a.12 b.34 c.2
d.14
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Structure -Neptune has a surface area of 7,618,272,763 km
-Neptunes length of day compared to Earths 24 hour day is 0d 16h 6m
-It has a mass of 1.024*1026 kg or (17.15 Earth mass) -Neptune is a
blue planet, and it is often thought of as an ice giant -The
internal structure of Neptune is mantle of water, ammonia and
methane ices, and a core of iron and magnesium-silicate -Neptune is
25 percent rock, 60 to 70 percent ice, and 5 to 15 percent hydrogen
and helium.
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Chemical Composition -Ammonia and methane is under Neptunes
atmosphere and is roughly 17 times Earth's mass and nearly 58 times
its volume - Ammonia ice, water ice, ammonia hydrosulfide, and
methane ice also compose Neptune's atmosphere. -Neptunes chemical
composition is Hydrogen (H) - 80 percent, Helium (He) - 19.0
percent, and Methane (CH4) - 1.5 percent -Neptune has 10-100 times
more methane, ethane, and ethyne at its equator than it does at its
poles
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Surface Conditions -Even though Neptune is far from the sun and
gets little sun to warm up its atmosphere, Neptune stills has winds
that reach high speeds. -Neptunes magnetic field is approximately
27 times stronger than Earths. -Like the other three gas giants,
the planet has no firm surface, so scientists have established that
the surface is where the pressure is equal to the pressure found at
sea level on Earth. - Just above the surface lies the troposphere.
As altitude increases, temperature in the troposphere decreases.
But in the next layer, the stratosphere, temperatures increase with
altitude. The next layer is the thermosphere, where pressure is
lower. The very outer edge of the atmosphere is known as the
exosphere.
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Mysteries 1.It is still a mystery that Neptune may rain
diamonds, as a diamond is composed of compressed carbon. Neptune
releases carbon which once hitting such a pressure point, could
result this way. 2.Some say, the great dark spot on Neptune is
believed to have been caused from the worst documented storm which
had actually lasted 5 years long..
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More Questions 1.Neptune was the _______ planet to be found
mathematically. 1First. 2Last. 3Only.
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More Questions 2.Neptune was visited by _____________.
1Voyager. 2Aliens. 3Hubble Craft. 4 None of the Above.
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True or False There is possibility for life on Neptune
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More Questions 2.Neptune was visited by _____________.
1Voyager. 2Aliens. 3Hubble Craft. 4 None of the Above.