Neptune

All About Neptune

By Madison Nef

Neptune’s discovery is considered to be perhaps the most exciting discovery in astronomy. It can’t be seen from a telescope, but it was first seen in 1846 from the observatory in Berlin. HOWEVER, the existence of the planet had been known for roughly a year before it was even seen.

Neptune is the 8th planet from the Sun.  Uranus, the 7th planet, was first discovered by means of a telescope in 1781.  Two astronomers; J.C. Adams in England and Urbain Le Verrierin France, had been puzzled by the shape of Uranus’ orbit. Using mathematics, they figured out that a larger and more distant body must be giving Uranus its strange orbit, pulling it closer during certain points in its orbit.

The Berlin observatory, following the calculations for the possible position of this then-unknown object, searched for Neptune and found it. It was named Neptune after the Roman God of the Sea.

In the same year that Neptune was first seen, 1846, its first moon was also spotted and named Triton. Triton is a most unusual moon since it orbits Neptune in the opposite direction of Neptune’s own rotation on its axis.  All the other major satellites (or moons) in the Solar System follow their planets around as they turn.

Triton is about the same size as our own moon.  A smaller moon, Nereid, was discovered by telescope in 1949 and six further moons were discovered in the 1980’s by the Voyager spacecraft.  All these moons are in between Triton and Neptune. Now, we are aware that Neptune has 13 total moons- since Neptune was the god of the sea, all of the moons were named after the less important Greek sea gods. This started with Triton and worked its way down to sea nymphs, like Nereid.

Neptune is the third largest planet in the Solar System, much smaller than the real giants, Jupiter and Saturn, and only a little bigger than Uranus. Giants? What? That’s right: Neptune is one of the four ‘gas giants’. Like the others, it is composed only of gas. Neptune is made up of hydrogen and helium.

Like all the other planets in the Solar System, Neptune moves in an orbit round the Sun at the center of the system.  It takes Neptune 165 of our Earth years to orbit the Sun.  The Earth orbits the Sun in 365 days (or one Earth year). In 2011, Neptune completed its first orbit of the Sun… since its discovery in 1846.

Like all other planets, Neptune turns on its own axis while orbiting the Sun. While the Earth makes a full revolution on its axis in 24 hours (one turn = one day), Neptune spins a bit faster, completing its turn in just 19 hours. This means that one day on Neptune is only 19 hours long.

The Earth is 93 million miles from the Sun; and this measurement is taken as the standard for astronomical measurements of distance.  Astronomers say that the Earth is one Astronomical Unit (1 AU) from the Sun.  Neptune is unimaginably further… at 30.1 AU from the Sun. This makes it 2793 million miles from the Sun, and 2700 million miles from Earth.

Well, I hope you enjoyed this paper and learned a little bit about Neptune. I know I did. I like the fact that all the moons were named after minor sea gods or people associated with the sea… it’s a nice touch and a good way to coordinate things and tie them all together. It’s also a great connection between ancient mythology and astronomy.

I’ll leave you here.

Maddie