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Neptune

The planet Neptune

 Automatic translationAutomatic translation Category: Planets and dwarf planets
Updated June 01, 2013

This photograph of Neptune was reconstructed from two images taken by the traveler through the 2 narrow-angle camera.
The image shows three functions that the traveler 2 photographed during her fly around Neptune. In the center, we see the Great Dark Spot, accompanied by bright clouds, white undergoing rapid changes in appearance.
South of the great dark spot shows another bright spot that scientists have dubbed "the Scooter".
More farther south, a smaller spot is called "Dark Spot 2," at the heart shine.
Each object of the atmosphere of Neptune is moving eastward at a different speed, so it is difficult to see them close to each other. Only rarely they appear close to each other.
2 The passenger is the only spacecraft that has visited the planet Neptune.
"A planet is a celestial body that is in orbit around the Sun, which has sufficient mass for its gravity overcomes the forces of cohesion of solid body and maintain hydrostatic equilibrium (spherical), which eliminated any body moving in an orbit close."
This definition was approved on 24 August 2006 at the 26th General Assembly of the IAU (International Astronomical Union) by a show of hands of about 400 scientists and astronomers after ten days of discussions.

 Planète Neptune

Image: photograph sent by traveler 2, this stunning image of storms in the windy atmosphere of Neptune was taken on 24 August 1989. Image credit: NASA.

nota: Neptune represents 3% of the total mass of the planets of the solar system.
 
Neptune Characteristics
   
Aphelion 4 526 874 325 km
Perihelion 4 459 631 496 km
Semi-major axis 4 503 443 661 km
Eccentricity 0,00858587
Orbital period 60 190.03  days
Average orbital speed 5.43 km/s
Mass 1.0243 x1026
(17.147 times the earth)
Equatorial diameter 49 922 km
Polar diameter 48 574 km
Inclination of the axis 29,58°
Longitude of ascending node  131.794310°
Orbital circumference 28.142 x 109 km
Argument of perihelion 265.646853°
Albedo 0.41
Escape velocity 23.5 km/s
Inclination to the ecliptic 1.76917°
Discovered date 23 September 1846
Satellites 14

Neptune, Poseidon in Greek

    

Neptune (Poseidon in Greek sea god) is the eighth and last planet in our solar system and appears with powerful instruments. It is 4,526 874 325 billion km from the Sun (30 times farther than Earth).
The French astronomer Urbain Le Verrier calculated the hypothetical position in the sky, the eighth planet, which was called Neptune.
It was discovered in 1846 at the predicted position. Neptune was not discovered by observation, but with pencil and paper from the trajectory and characteristics of Uranus.
Neptune, like all the Jovian planets have rings discovered from 1984, but their existence has been confirmed by Voyager 2 in 1989, 3 key rings very narrow and dark orbit around the planet.
The blue color of Neptune is the result of absorption of red light by methane in its atmosphere.
The atmosphere of Neptune has a thickness of more than 8 000 km. It is composed primarily of hydrogen (H2) for 85%, helium (He) for 13% and methane (CH4) to 2%.
In the 1960s, in the outer solar system, it was spring in the southern hemisphere of Neptune.

 

As Neptune goes around around the Sun every 165 years, i.e. 41.5 years last season, now it's summer for southern Neptune.
Astronomers have found that in recent years Neptune has been particularly brilliant, as shown in this beautiful image of the Hubble Space Telescope in 2002.
Compared to the pictures taken by Hubble, in 1996, the 2002 image shows a large increase in reflective white cloud bands in Neptune's southern hemisphere.
The Neptune's equator is tilted 29.58 degrees to the plane of its orbit, much like on Earth (23.5 °).
The weather on Neptune seems to be changing dramatically with the seasons, despite the low intensity of light that reaches the sun. It is 900 times less intense than on Earth.
Since 2005 and for 40 years, it's summer in the southern hemisphere of Neptune.

Image: Since 2005, it is summer in the southern hemisphere of Neptune and another 4 decades.

 Neptune

Moons of Neptune

    

Neptune (Greek Poseidon, god of the sea) is the 8th and final planet in the solar system and might prove as powerful instruments.
It is 4 526 874 325 km of the Sun (30 times farther than Earth).
The French astronomer Urbain Le Verrier calculated the hypothetical position in the sky, the eighth planet, known as Neptune.
It was discovered in 1846 in the position predicted.
Neptune was not discovered by the observation, but with pencil and paper from the trajectory and characteristics of Uranus.
Neptune planets like Jupiter have rings discovered in 1984, but their existence has been confirmed by Voyager 2 in 1989, 3 key rings and dark narrow orbit of this planet around.
The blue color of Neptune is the result of absorption of red light by methane in its atmosphere.

 
Moons of
Neptune
diameter
(km)
Semi-major
axis (km)
     
Triton ≈2 706 354 759
Proteus ≈420 117 646
Nereid ≈340 5 513 818
Larissa ≈194 73 548
Galatea ≈176 61 953
Despina ≈150 52 526
Thalassa ≈82 50 074
Naiad ≈66 48 227
Halimede ≈62 16 611 000
Neso ≈60 49 285 000
Sao ≈44 22 228 000
Laomedia ≈42 23 567 000
Psamathe ≈40 48 096 000
S/2004 N1 ≈18 105 283
 Triton lune de Neptune

Image: Triton is the seventh and the largest satellite of Neptune. Its orbit is retrograde (opposite direction of rotation than the rotation of Neptune).

See also

     
Seven Wonders of the World
The Seven Wonders
of the World...
      
      
 
star
 
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