Parc del Garraf

Diameter

Neptune is the furthest planet from the Sun, only visible with optical instruments, even if they are simple binoculars. It is a gaseous planet, like Jupiter and Saturn, but having a relatively higher presence of oxygen, carbon and nitrogen it is also called an "ice giant", like Uranus. According to Greek mythology, Neptune is the god of the oceans.

Duration of the day

The day on Neptune is considerably shorter than ours. It lasts 16 hours and 6 minutes.

Year duration

To experience a year on Neptune we would need to live as long as a giant Galapagos tortoise: 165 years.

Distance to the sun

It is about 30 times farther from the Sun than we are, at 4.5 billion km. 4.5 kilometers from the Sun in this model represented at Garraf.

Satellites

14 satellites are currently known. The largest is Triton, 2,700 km in diameter.

Composition

It is a huge sphere of gas, mostly hydrogen and helium but with a significant proportion of water ice, ammonia and methane.

Surface temperature 

At the level of the atmosphere equivalent to the pressure of a terrestrial atmosphere, the temperature is 200 °C below zero. In the interior they surely reach 5,000 °C.

Gravity

We would weigh 10% more than on Earth.

Density

1.6 g / cm³. Similar to the density of magnesium.

Did you know...

… That from Neptune the Sun is just a point in the sky? But it is so bright that at noon we would notice a luminosity like here at sunset. … That light we see from Neptune takes 4 hours to reach us? And think that the sunlight that illuminates it also takes 4 hours to reach Neptune. If the Sun went out right now, we could still see Neptune for 8 hours.