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Discovering the Four Dwarf Planets

You may have heard of Pluto, Haumea, Ceres, and Eris, but did you know they are also considered dwarf planets? If so, then you’re in for a treat! Read on to discover more about these fascinating bodies. Also read about their history, and why they are important for humankind. Then, you can use your knowledge of these objects to further your career and explore the Universe. This article introduces the four dwarf planets and their fascinating histories.


During a recent space mission to Mercury, we learned about another of the four dwarf planets, Haumea. The team used telescopes at 10 different laboratories to observe the planet from its own perspective. A scientist explains that the dwarf planet’s shadow appears full size when viewed from a distance. That’s the same as seeing the dwarf planet’s shadow projected on a star. Haumea’s axial length is approximately 1,430 miles, or 2,300 kilometers.

The orbit of Haumea is incredibly eccentric, with a ring encircling the planet. This ring is 70 km wide, and is in the plane of Haumea’s equator. The ring’s particles revolve in a 3:1 resonance with the dwarf planet’s rotation, completing one full revolution in every three Haumea rotations. Despite this odd rotation, scientists haven’t managed to land on the dwarf planet yet.

A rocky body with a thin layer of ice on its surface, Haumea is one of the densest objects in the Kuiper belt. It has an albedo of 0.6-0.8 and an average density of 1.885 grams per cubic centimeter. Its surface is covered with an icy coat, and scientists believe that it has no life potential. Since it was discovered only recently, more information about Haumea can be obtained through more advanced imaging techniques and detailed data.

The size and shape of Haumea’s elongated disk were thought to have been caused by a collision with a giant object billions of years ago. Its rapid rotation, ring-like structure, and high albedo are all features of a collision-prone system. Haumea’s moons are named after the goddess of childbirth in the Hawaiian language. The moons of Haumea are named Namaka and Hiiaka.


Ceres is a dwarf planet found in the asteroid belt between Jupiter and Mars. The Dawn spacecraft collected data about Ceres during its final orbits before running out of fuel. This mission found evidence of briny liquid seeping from the surface, and mounds and hills resulting from the melting of ice. Scientists speculate that this could have resulted from an asteroid impact 20 million years ago.

The surface of Ceres is covered with countless small craters that are less than 300 kilometers wide. It also contains a thin atmosphere made up mostly of water vapor. The water vapor came from ice sublimation and ice volcanoes. Ceres’ atmosphere is relatively warm compared to other asteroid’s surface temperature. However, it may be possible that there is a liquid ocean beneath the surface of Ceres.

Scientists say Ceres formed around 4.5 billion years ago when the Solar System was forming. It was pulled by the gravitational forces of planets to form but it never fully developed as a planet. It probably formed in the outer solar system where ammonia was more abundant and the Sun did not vaporize it. Its gravitational influence brought Ceres to its present location.

The discovery of Ceres has prompted debate and confusion about the planet’s proper classification. Although no direct observation of Ceres has been made since its discovery, its existence has fueled speculation for decades. A few centuries ago, Johann Elert Bode, an astronomer in Germany, speculated that there must be a planet between Jupiter and Mars. The Bode-Titius law, based on a proposal by Johann Daniel Titius in 1766, ruled that there must be a planet between Mars and Jupiter.


While the eight planets of our solar system are large, smaller objects are also classified as dwarf planets. In 2006, Catherine Cesarsky, president of the IAU, reclassified Pluto as a dwarf planet. Pluto, which is about a trillion miles from Earth, shares its orbit with two icy bodies in the Kuiper Belt. The reclassification of Pluto did not mean that it had been demoted, but instead was an effort to promote the concept of dwarf planets.

Today, Pluto is classified as one of four dwarf planets, along with Eris, Charon and Makemake. The names of Pluto and Eris were originally derived from the Greek god of discord, Makemake. Today, these four icy bodies are still under study, but the discovery of these objects forced astronomers to reconsider the classification of Pluto. The discovery of Makemake, which is not yet visible with current instruments, forced the reclassification of Pluto. Although scientists cannot observe Pluto’s surface, they have detected frozen methane and ethane ice.

Pluto is a complex world. It is roughly the size of the United States and lies in the Kuiper Belt, a region beyond the orbit of Neptune. It is approximately two-thirds the size of Earth and its biggest moon is only half its mass. Pluto travels around the Sun in an oval-shaped orbit, tilted compared to other planets. While it is small, Pluto is the closest object to the Sun.

Pluto has five moons. Its largest moon is Charon, which is roughly half its size. Pluto’s moons may also be considered a binary system, as they have barycenters outside their orbits. Nevertheless, they are still regarded as “dwarf planets.”


Scientists have discovered another dwarf planet: Eris. Its mass is approximately 27 percent larger than Pluto’s and is similar in appearance to the asteroid 433 Eros. Eris has an icy surface and is thought to have an internal ocean. This research may be one of the reasons that the planet can support liquid water. Eris may be capable of supporting liquid water if it is located near the mantle-core boundary.

The IAU definition of a dwarf planet was approved in August 2006. It defined the qualifications for a planet to be a dwarf planet. Eris was a candidate because it is smaller than Pluto. It also lacks a moon or satellite, which can lead to its status as a dwarf planet. The IAU definition reduced the number of known planets to eight. In addition to Eris, Pluto and Haumea are also dwarf planets.

Ceres is the largest asteroid in the asteroid belt between Mars and Jupiter. Its orbital path is still unclear, so it qualifies as a dwarf planet. During its series of orbits, it will collect data and help scientists better understand the asteroid belt. It will arrive at Ceres in about four years. And while it has a large rocky core, its surface is covered with traces of minerals. This means that it could have once hosted life on earth.

In the last few decades, Pluto has become the prototype of a new class of bodies called plutoids. Pluto’s resolution is still in place, but it is an example of how science works. It reflects changes made through observations, measurements, and theory. The new designation of Pluto will be the first of many. It will be located near Jupiter and Mars in 2036. And after that, it will move into the Aries constellation in 2065. From there, it will move northward. It will eventually pass through the constellations Perseus and Camelopardalis.


The name of Varda comes from the Valar, the creators of the stars and powerful servants of Eru Iluvatar. This rocky world is still a candidate for a dwarf planet, although its size and density raise questions about its status. With a surface diameter of 740 kilometres, it orbits the Sun every 449 years. Its mass and density are unknown and researchers need more data to make a proper assessment of its mass and density.

The estimated density of Varda was found to be 1.78+-0.06 g/cm3 in a recent analysis by Grundy et al. A year after the initial assessment, Grundy et al. published an estimate that found Varda to be very close to Quaoar’s density. While this is far from the exact number of g/cm3, it does provide a more accurate picture of its size and density.

The orbit of Varda is highly eccentric, bringing it as close as 39 AU to the Sun while further out at 52 AU. This puts it in the company of the cubewanos, which pursue paths through the transneptunian region known as the Kuiper Belt. Varda is currently on its inward leg of its 311-year passage around the solar system. It will eventually reach its closest point to the Sun, perihelion, in the last few years of the 21st century.

Scientists have identified five other celestial objects that meet the criteria for a dwarf planet. Currently, there are five recognized dwarf planets – Pluto, Eris, Haumea, and Makemake. In addition to these, there are likely thousands more such bodies in the Solar System, which make the number even greater. When it comes to astronomy, there are numerous theories for the existence of thousands more.