Neptune's Features

Neptune's Characteristics:
is a unique planet made up of mostly three different gasses. Neptune is 74% Hydrogen, 25 % Helium, and 1% Methane.
Neptune appears blue because of the gasses it is composed of. Neptune is broken down into four layers: the Upper atmosphere, Atmosphere, Mantle, and Core. Within those layers, different materials and elements make up Neptune. For example clouds are found in the upper atmosphere. Hydrogen, helium, and methane are found in the atmosphere. Water, ammonia, and methane ices found in the mantle. Also rock and ice are found in the core of Neptune. Knowing that there is ice on Neptune, saying this planet is cold is a safe assumption. Neptune is 2,795,084,800 miles or 4,498,252,900 kilometers away from the sun on averageNeptune is the farthest plant from the sun getting the least amount of heat and light from the sun. Thick ice forms in the deep mantle and inner core.   Knowing this, that is why no astronaut has stepped foot on Neptune.

Neptune's Moons

Data for Neptune's Moons


Discovery Date
Distance from Neptune (103 km)
Mass (1020 kg)
Radius (km)
Orbital Period (days)
Naiad (NIII) 1989 Voyager 2 48.227 0.002 29 0.294
Thalassa (NIV) 1989 Voyager 2 50.075 0.0004 40 0.311
Despina (NV) 1989 Voyager 2 52.526 0.02 74 0.335
Galatea (NVI) 1989 Voyager 2 61.953 0.04 79 0.429
Larissa (NVII) 1989 Voyager 2 73.548 0.05 104x89 0.555
Proteus (NVIII) 1989 Voyager 2 117.647 0.5 218x208x201 1.122
Triton (NI) 1846 W. Lassel 354.76 214 1353.4 5.877*
Nereid (NII) 1949 G. Kuiper 5513.4 0.3 170 360.136
S/2002 N1 2002   15,686 0.001 24 1874.8
S/2002 N2 2002   22,452 0.001 24 2918.9
S/2002 N3 2002   22,580 0.001 24 29.82
S/2002 N4 2002   46,570   30 8863.1*
S/2003 N1 2003   46,738 0.0002 14 9136.1*

table from

    Moon- A moon is a structure that orbits around a planet out of it's atmosphere . Neptune has 13 known moons. 11 of Neptune's moons are not visible from earth. Scientists in the late 18 hundreds and early 19 hundreds spotted Triton and Nereid by telescope. Astrologists began to discover Neptune's moons when NASA started sending humans and surveillance equipment into outer space.


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Neptune has 9 rings. They were discovered in the late 1980s by Voyager 2. The smallest ring that stretches across Neptune is 41,900 Km long. Neptune's largest ring is 62,900 km. Neptune's rings are made up of dust particles that were left over when the planet was created. They then fell into the planet's orbit and created rings. The rings are difficult to see without taking quality satellite images.

Gravity- Neptune is made up of gasses so its impossible to walk on, but if you could walk
on Neptune's surface, you would weight 1.14 times heavier on Neptune. If you weighed 100 pounds on earth, you would weigh 114 pounds on Neptune. This is because Neptune is is 1.14 times bigger than earth having 1.14 times the gravity on Neptune than on earth. The more surface area a planet has, the more gravitational force pushes down on the planet. This is similar to Buoyancy. The more surface area an object has, the more force can push upon it to make it float. The moon is smaller than Earth allowing it to have less gravitational force. That is why astronauts can float on the moon

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