Skip links

Neptune 10 Interesting Facts For Kids


Neptune, or the “Blue Giant,” is the eighth planet in the solar system, making it the farthest from planet from the Sun as well. It is called the Blue Giant because it has a deep blue color similar to the ocean, which is why it was named after the Roman God of the sea. There are plenty of other interesting facts about Neptune. Some of these you may know already, and others may be new to you.

1. Neptune was not always the farthest planet from the Sun.

Neptune was discovered in 1846, and originally given this title until the discovery of Pluto in 1930. Pluto held the title as the farthest planet from the Sun for 76 years. Then, in 2006 the International Astronomical Union decided to reclassify Pluto as a dwarf planet, giving Neptune back its original standing. However, there are scientists who disagree with this reclassification, so you never know, Pluto may be classified as a major planet once again.

2. Neptune was only studied up close one time.

On August 25, 1989 the Voyager 2, which is an unmanned interplanetary space probe, made a flyby within thousands of miles of the planet’s north pole. While making its flyby, the Voyager 2 also discovered what famously became known as the “Great Dark Spot,” which was a large spot that scientists are still unsure of. However, most believe it was a storm cloud or a hole in a storm cloud. There are no plans to revisit the planet.

3. Neptune is the coldest planet in the solar system.

Since Neptune is the farthest planet from the Sun, it is also the coldest. This is because it does not get as much of the Sun’s heat. The planet’s outer atmosphere is about -218 degrees Celsius. However, its center temperature is around 5,000 degrees Celsius.

4. Neptune possesses a ring system.

It was disputed whether Neptune actually had a ring system until the Voyager 2 confirmed it in 1989. Its rings are nowhere near as large and noticeable as Saturn’s, which is partly the cause of the dispute. The five rings are called the Adams Ring, the Le Verrier Ring, the Lassell Ring, the Arago Ring, and the Galle Ring. The rings are believed to be made of ice particles, and they have a reddish color to them.

5. There are two known moons of Neptune and six moonlets.

The first discovered moon, Triton, was found by William Lassel only 17 days after the planet’s discovery. The Voyager 2 discovered six of these moons, which is more than half of them, in three months during part of its 1989 voyage. The moon, Triton, is named after the son of the Greek God, Poseidon. Poseidon is simply the Greek name for Neptune. The Greeks and Romans had the same Gods, but they used different names.

6. Neptune has not completed a full rotation since its discovery.

Because of Neptune’s great distance from the Sun, it takes between 164 to 165 years to make a full orbit. However, on July 12, 2011 Neptune will have made one orbit since its discovery. In addition, because the earth orbits at a different rate, it will not be in the position it was found in 1846. It is not currently known when it will be in the same position as its discovery date again.

7. Neptune’s winds are the strongest in the solar system.

The winds on this planet can reach speeds up to 2,100 kilometers an hour. Neptune is plagued with massive storms, larger than anyone on Earth has ever even come close to experiencing. It is believed that the “Great Dark Spot” was one of Neptune’s mammoth storms. One reason scientists believe the spot was a storm was because it disappeared five years later, but a new, similar spot was found in the Northern Hemisphere, implying a storm’s movement.

8. No human could ever walk on the planet’s surface.

Neptune has a rocky core, but outside of that, it is a swirling ball of ice and gas. The main gases in Neptune’s atmosphere are helium, hydrogen, and methane. It also contains water, ammonium hydrosulfide, and ammonia. Methane is the reason for the planet’s blue color. When sunlight enters the atmosphere, the red light is absorbed by the methane, reflecting blue light back out.

9. You cannot see Neptune without a telescope.

Since Neptune is about 30 times as far from the Sun as Earth, it cannot be seen by the naked eye. To further display this distance, it is 5,900,000,000 kilometers or about 3,666,090,034 miles from the Sun to Neptune. It is exceptionally far, and simply will never be seen without magnification.

10. Neptune has its own heat source.

Since Neptune is so far from the sun, it depends on its own heat source. This heat is generated internally, and throws frozen gases out. Scientists believe this is the reason for Neptune’s severe storms and winds.

Those are just some of the more interesting facts about the Blue Giant. Scientists often make new discoveries about Neptune as time passes. Unfortunately, no one wishes to study the planet up close again, so much of what could be learned is likely to remain a mystery.