This is a picture of the scooter. The most pronounced of the irregular clouds.
Neptune
was discovered 1846, in a large number of places. It was first believed
to exist, when astronomers looking at Uranus noticed that there was a bit
of imbalance, that could only be caused by the gravity of another great
celestial body pulling on it. In 1845, the first astronomical theorist
to work on the problem was a young British man named Adams, who accurately
predicted where the planet would be found in the night sky.
However he failed to find support for his discovery, and could persuade
no experimentalists to look where his predictions showed for a new planet.
A year later, a French theorist of some repute named LeVerrier, took up
the project. He found where the planet should be, and published a
paper about it, containing his measurements for the planet's position in
the sky. The measurements were almost exactly the same as those of
Adams. The experimentalists who took up the project after reading
LeVerrierís paper were a team of Germans called Galle and deArrest.
They found a new disk like object in the sky where LeVerrier had predicted
it to be. The discovery of Neptune is credited to Adams and LeVerrier
for they accurately predicted the position of Neptune. Most
all other discoveries that had anything to do with Neptune were made by
the Voyager II Space Probe, the only space craft ever to reach Neptune.
Most everything that the report has to say about discoveries say ìDiscovered
by Voyager II in 1989î
Neptune, is the eighth and sometimes the
ninth planet from the sun. It is sometimes the ninth due to the eccentricity
of the orbit of Pluto, which crosses that of Neptune at several places.
In relation to Uranus, it is smaller around, but composed of heavier material.
Its orbit is 4, 504,000,000 kilometers from the sun. The diameter
at the equator is 49,532 kilometers. It weighs 1.0247 e 26 kilograms,
which translated out of scientific notation is 102,470,000,000,000,000,000,000,000
kilograms. Neptune's day (one complete rotation) is: 16 hours,
and one year (one complete rotation around the sun) is 165 earth days.
Neptune , has a composition rather similar
to its neighbor Uranus, the seventh planet from the sun. It has a
rocky core, about the size of earth, that is covered with frozen water,
helium, and hydrogen. That is surrounded by thick, dark clouds of Hydrogen
Sulfide. The inner atmosphere of Neptune is probably at its solid
state. Hydrogen sulfide is also a major component of skunk juice.
The outer atmosphere is a good number of clouds composed of Methane, Helium,
and Hydrogen. These are probably in their liquid form. Neptune
also has a pretty good number of small white clouds, that go around the
planet aimlessly. Neptune has vaguely similar basic structure to that of
the other gas planets. However, the particulars are all unique
to the planet.
This is a picture of the scooter. The most pronounced of the irregular clouds.
Neptune
has particularly turbulent weather. It has very powerful winds, that
blow at an average speed of 960 kilometers per hour. The greatest
speed these winds have reached is 2000 kilometers per hour. It has
a large number of rather violent storms. The most pronounced of which
is (or was) the Great Dark Spot. It was discovered in 1989 by Voyager
II. This particular storm goes around the planet at a speed of 1,120
kilometers. Voyager II also found another storm of the same sort,
in the southern Hemisphere. However, when the Hubbell Space Telescope
observed Neptune in 1994, it found no evidence of the Great Dark Spot.
It did find a new storm in the northern Hemisphere. Most scientists
think it has either dispersed or is masked by other aspects of the atmosphere.
There is also a major irregular white cloud, that goes around the planet
once every 16 hours. This cloud is known as ìThe Scooterî.
The observations, that Voyager II made, compared with those of the
Hubbell Space Telescope show that Neptune's weather changes rather rapidly.
Neptune's atmospheric conditions, are rather similar to that of the other
giant gas planets. I also have my own theory, about the Great Dark Spot.
It is that the spot is a great and short lived vortex in the upper atmosphere,
showing the darker lower atmosphere. It probably takes place due to variations
in the magnetic field of Neptune which is very strong but has thin places
for some very strange reasons. The Great Dark Spot probably disappeared
because of a fluctuation in the magnetic field.
Neptune has eight moons, and all but two were discovered by the Voyager
II fly-by in 1989. The largest moon, Triton, has a large number of
interesting traits. But the basic information comes first.
Triton orbits 354,760 km. from the center of Neptune. It is 2,700
kilometers around at the equator, and weighs 2.14 e 22 kilograms.
That figure translated from Scientific notation, is 21,400,000,000,000,000,000,000
kilometers. It was discovered by a man named Lassal in 1846, in fact
only a few weeks after Galle and DeArrest proved that Neptune existed.
Triton has a very interesting attribute, that it orbits Neptune, contrary
to the direction Neptune orbits the sun. This means, that it is moving
slightly closer to Neptune with every orbit it makes. This will either
result in a collision with Neptune, or Triton breaking into little pieces.
The only other moons that orbit this way, are a number of Jupiter and Saturn's
smaller moons. Triton is the only major moon that orbits in
this fashion. All of the other interesting things about Triton were
discovered by Voyager II. Triton has a very minor
atmosphere that is composed of nitrogen, and methane. It also
has a very large polar ice cap, that covers most of the This cap is composed
of frozen nitrogen and methane. It probably exists because Triton's
surface temperature is -235 degrees C. This is as cold
as the surface of Pluto. At that extreme cold, all the gasses on
the surface will freeze solid. The most interesting of all Triton's
interesting features are the ìIce Volcanoesî. These volcanoes erupt
a mixture of frozen methane nitrogen, and very cold dust. One of
the main reasons they were discovered is that one was erupting when Voyager
II passed by. The plume it made was 8 kilometers high, and spread for 150
kilometers down wind. This also makes Triton one of the only
volcanic bodies in the solar system. It shares this title with Venus,
Earth, Mars, and Io ( one of Jupiter's moons). One of
the open ended questions about this small celestial body, is what force
powers these volcanoes. Next by size, comes the moon Proteus.
This is a picture of Triton the largest moon of neptune. To see more a detailed description of this moon see text above.
Proteus is the second moon of Neptune, by
size. It is 117,600 kilometers away from Neptune, and an average
diameter of 418 kilometers. That is derived from the measurements of 436x416x402
kilometers. It was discovered by Voyager II in 1989. It was
not found earlier due to the fact that it is dark and very close to a very
bright planet. It is heavily covered with craters, showing
no signs of any geologic activity whatsoever. This moon is
irregularly shaped as well. It is probably as big as an irregular
body can get, without its gravity pulling itself into a perfect sphere.
The next moon is Neried. It was discovered
by a ground based observation in 1949 by the famous astronomer Kuiper.
(The Kuiper Belt is named after him.) It orbits at an average distance
of 5,513,400 kilometers away from Neptune. It has a diameter of 340
kilometers. Neried has the most eccentric orbit of any satellite
in the solar system. It varies from 9,623,200 kilometers, to 1,350,600.
The figure 5,513,400 kilometers, is obviously the median between the greatest
and the lowest distance. The nature of the orbit probably means that the
moon is a captured asteroid or Kuiper Belt item. Next on the list
comes Larrisa, which the honor of discovery is disputed between ground
based observation by Harold Rightsma, or Voyager II. Both saw it
in 1989. It is 73,600 kilometers away from Neptune, and has a diameter
of 193 kilometers. It has a surface, much like that of Proteus with
many craters and nothing else. The next, is Galatea, which orbits
73,600 kilometers away from Neptune, and has a diameter of 158 kilometers.
Next is Despina, with a diameter of 148 kilometers, and a distance
from Neptune, of 52,600 kilometers. Thalassa comes after Despina
with a distance of 50,000 kilometers away from Neptune, and a diameter
of 80 kilometers. The last moon is Naiad, with a diameter of
58 kilometers and a distance from Neptune of 48,200 kilometers. All
these moons were discovered by Voyager II in 1989. All of Neptune's
moons except for Triton, are almost unknown.
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Arrnet, Bill http://www.seds.org/nineplanets/nineplanets/
Fradin, Dennis B. Neptune. Children's Press ®. Chicago
Illinois,©1990.
http://www.pantheon.org/mythica/areas/greek
http://www.pantheon.org/mythica/areas/roman
Panada, Carlos http://hsa.brown.edu/~maicar/.
©1997
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