Dwarf planets are usually smaller than Mercury, and they don't dominate their region of space. The first classified dwarf planet was Pluto in 2006.
Key Facts & Summary
- Dwarf planets are relatively small; for example, the largest dwarf planet in our Solar System, Pluto, is two times smaller than the smallest planet in our Solar System, Mercury.
- Pluto was considered a planet for a long time; however, after many other small planets were discovered, Pluto was classified as a dwarf planet.
- There are currently five confirmed dwarf planets in our Solar System, namely Pluto, Eris, Makemake, Haumea, and Ceres.
- There may be more dwarf planets near us, but they are yet to be confirmed.
- The largest of these dwarf planet is Pluto, while the smallest is Ceres.
- Pluto has a diameter of 2,376 kilometers / 1,476 miles, while Ceres is at 946 km / 587 mi.
- Ceres is also classified as an asteroid, the largest known in our Solar System.
- Pluto was considered a planet for 75 years. This changed in 2006 when Eris was discovered.
- Pluto is also the first Kuiper Belt object to be discovered. The Kuiper Belt is a region filled with many asteroids surrounding our Solar System. It is located beyond the farthest planet, Neptune.
- Many still consider Pluto as a planet, and rightfully so. It is quite a beautiful and rich world.
- Dwarf planets are common in our Galaxy. Astronomers believe that there may be around 200 dwarf planets just inside our Solar System.
- Dwarf planets can have moons of their own. Pluto, for example, has a moon named Charon, and it is quite big.
- Some dwarf planets may have a ring system, just like Saturn does.
- It is not yet clear if life can evolve on dwarf planets since they are usually very far away from the Sun.
Dwarf Planets for Kids
The differences between planets and dwarf planets are not yet fully underlined. Pluto was considered for 75 years a planet until similar celestial objects were discovered.
What is a Dwarf Planet?
A dwarf planet is a celestial object similar to a planet but much smaller. They haven't cleared the area around their orbit, while planets have already done this.
What are the Five Dwarf Planets of our Solar System?
The five dwarf planets of our Solar System are Pluto, Eris, Makemake, Haumea, and Ceres. Pluto was the first classified dwarf planet, while Ceres is also classified as an asteroid.
Here are the diameters of the most famous dwarf planets:
Pluto – 2,376 kilometers / 1,476 miles
Eris – 2,326 km / 1,445 mi
Haumea – 1,632 / 1,014 mi
Makemake – 1,430 km / 888 mi
Ceres – 946 km / 587 mi
There are many more dwarf planets in our Solar System, such as Sedna, Quaoar, Orcus, or Gonggong, but they are still under debate. Some astronomers believe that there may be over 200 dwarf planets just inside our Solar System, but we have yet to find them.
What Makes a Dwarf Planet Different From a Planet?
Dwarf planets are very similar to planets. They can have moons, just like planets, or ring systems. Pluto, for example, has one moon, namely, Charon.
The dwarf planet Haumea has a ring system just like Saturn, but it is very small and faint in comparison. The only difference between dwarf planets and planets is the fact that dwarf planets are smaller, and they haven't cleared up their region of space as planets did.
Fun Kids Facts Dwarf Planets
- The dwarf planet Haumea is shaped just like an egg due to gravity.
- The closest dwarf planet to us is Pluto, as it occasionally comes closer to the Sun than Neptune.
- Pluto's moon Charon is almost as big as the dwarf planet itself.
- In theory, if there are around 200 dwarf planets in our Solar System alone, then this means that dwarf planets are far more numerous than planets in the Universe.
- Some believe that life may have come from the dwarf planet Ceres.
- Though many consider Pluto a dwarf planet, many also consider it a planet. In the end, both answers are correct.
Size and Comparison
The biggest dwarf planet in our Solar System is Pluto, which has a diameter of 2,376 kilometers / 1,476 miles. The smallest dwarf planet is Ceres, with a diameter of only 946 km / 587 mi
The second biggest dwarf planet is Eris, at 2,326 km / 1,445 mi, followed by Haumea at 1,632 / 1,014 mi, and then by Makemake at 1,430 km / 888 mi.
The smallest planet in our Solar System is Mercury, which has a 4,879 km / 3,031 mi diameter; however, Mercury is twice as big as the biggest dwarf planet, Pluto.
Simultaneously, Jupiter, the biggest planet in our Solar System, is 29.3 times bigger than Mercury; thus, Jupiter is more than 58.6 times bigger than Pluto.
Who discovered Pluto?
The astronomer who discovered Pluto was Clyde Tombaugh. This happened on February 18, 1930. Pluto was considered the ninth planet of the Solar System for 75 years.
In 2006, Pluto was reclassified as a dwarf planet, the first of its kind, after the discovery of Eris, another dwarf planet.
How Many Dwarf Planets are There?
There are five official dwarf planets in our Solar System, Pluto, Haumea, Eris, Makemake, and Ceres. There are other dwarf planets such as Sedna, Quaoar, Orcus, or Gonggong, but their status is still disputed.
Astronomers believe that there could be as many as 200 dwarf planets in our Solar System.
Can Dwarf Planets Host Life?
Some scientists theorize that life came to Earth from Ceres, the asteroid dwarf planet. It is currently unknown if dwarf planets can host life; however, they are usually situated very far from the Sun.
If dwarf planets come into the Sun's habitable zone, and if they possess the right elements, it is quite possible that they may host or develop life. Somewhere out there, in the vast Universe, the chances are high that a dwarf planet may host life nonetheless.
What is the Fastest Dwarf Planet?
The fastest dwarf planet is the egg shaped Haumea. The reason for its weird shape is also attributed to its rapid rotation since the dwarf planet spins once every four hours.
Dwarf Planets Notes
- Dwarf planets are not planets, but they can have moons of their own or their own ring systems.
- Dwarf planets are considerably smaller than planets, and they haven't cleared up their region of space, as planets have done.
- The first unofficially discovered dwarf planet is Pluto.
- The biggest dwarf planet is Pluto, while the smallest is Ceres, who is also classified as an asteroid.
- There are more than five dwarf planets in our Solar System, but they have yet to be officially accepted.