Why Pluto is not a Planet?

Why Pluto is not a Planet? In our solar system due to a reclassification by the International Astronomical Union (IAU) in 2006. Here’s why:

Discovery and Initial Classification:

Pluto Discovery: Clyde Tombaugh made the discovery of Pluto in 1930, and at first it was ranked as the ninth planet in our solar system. It was thought to be the outermost planet, orbiting beyond Neptune, for many years.

New Discoveries and the Need for a Definition:

The Kuiper Belt: During the latter part of the 20th century, astronomers made numerous discoveries in this region of the solar system, which is made up of small, frozen bodies and extends beyond Neptune. Pluto’s size was comparable to some of these objects, raising doubts about Pluto’s continued status as a planet.
Finding of Eris: The 2005 discovery of Eris, celestial object somewhat bigger than Pluto, heightened discussion. Pluto would still need to be considered a planet in order for Eris and maybe a large number of additional objects to be included in this classification.

The IAU’s New Definition of a Planet:

The Resolution from 2006: In response, the International Astronomical Union (IAU) developed a precise definition of a planet. A celestial body can only be classified as a planet if it satisfies three requirements, as stated by the IAU:

It has to revolve around the Sun.
It must have enough mass for gravity to draw it into a round shape, which means it must have a spherical form.
It must have “cleared the neighborhood” around its orbit, which means that most other objects in its orbit have been displaced by it and it has gained gravitational dominance.

Why Pluto Doesn’t Qualify:

Orbit: Because Pluto is spherical in shape and orbiting the Sun, it satisfies the first two requirements.
Clearing the Neighborhood: Pluto, however, does not satisfy the third requirement. Its orbit shares space with other bodies of a similar size in the Kuiper Belt and overlaps with other objects’ orbits. The IAU does not consider it to be a planet because it has not left its orbital neighborhood.

Pluto’s New Classification:

Dwarf Planet Status: Following the IAU’s ruling, Pluto was given a new designation of “dwarf planet.” Celestial bodies that satisfy the first two requirements of a planet but have not yet left their orbital neighborhood are known as dwarf planets.
Pluto’s Persistent Significance: Even after being reclassified, Pluto is still a significant and fascinating subject of astronomical research. The 2015 New Horizons mission revealed Pluto’s intricate atmosphere and geology through exquisite photos and data.

Features Of Pluto:

Diameter: Pluto is approximately 18.5% the size of Earth, with a diameter of 2,377 kilometers (1,477 miles).
Composition: Pluto is primarily made up of ice and rock. Its interior is thought to be differentiated, consisting of a mantle of water ice around a rocky core.
Surface Area: The surface area of Pluto is nearly equal to the surface area of Russia, at 16.7 million square kilometers (6.4 million square miles).
Planitia Sputnik: One of the most identifiable landforms on Pluto is Sputnik Planitia, a huge, heart-shaped plain composed of nitrogen and methane ice. It is thought that a sizable impact crater filled with volatile ices formerly existed, leaving behind this basin.
Mountains: Water ice mountain ranges can be found on Pluto, with some of its peaks rising as high as 3,500 meters (11,000 feet). The Hillary and Tenzing Montes are two of the most famous ranges.
Craters:Impact craters dot Pluto’s surface, yet certain areas have fewer craters than others, suggesting they are older geologically.
Glaciers:Nitrogen ice glaciers flow throughout the surface of Pluto, especially in Sputnik Planitia. On the dwarf planet, these glaciers are a component of a dynamic geological process.
Pluto’s atmosphere is thin, primarily made up of nitrogen with small amounts of carbon monoxide and methane. Up to 1,600 kilometers (1,000 miles) are covered by Pluto’s atmosphere.
Seasonal Variations: There are notable seasonal variations in Pluto’s atmosphere. Pluto’s atmosphere grows as it approaches the Sun in its eccentric orbit because surface ices sublimate. The atmosphere may freeze and return to the surface as it travels away.
Haze Layers:Pluto’s atmosphere is theorized to be composed of several layers of haze that are created by photochemical reactions triggered by sunlight breaking down methane.
Charon: At 1,212 kilometers (753 miles) in diameter, Charon is the biggest moon of Pluto and is roughly half the size of Pluto itself. Since Charon and Pluto orbit a point in space apart, Charon is so big in relation to Pluto that they are frequently referred to as a twin dwarf planet system.
Other Moons: Nix, Hydra, Kerberos, and Styx are the four smaller moons of Pluto. These moons are far smaller than Charon and have a strange form.
Elliptical Orbit:Pluto’s orbit is extremely elliptical, causing it to be between thirty and forty-nine astronomical units (AU) from the Sun. This indicates that during its 248-year orbit, Pluto’s distance from the Sun varies considerably.
Rotation:Pluto rotates retrogradely, which means that it spins in the opposite direction as the majority of the solar system’s planets. About 6.4 Earth days pass throughout its day (one spin), which is the same amount of time that Charon takes to orbit Pluto.
Extreme frigid: The surface temperatures of Pluto range from roughly -375 to -400 degrees Fahrenheit (-226 to -240 degrees Celsius). Pluto is an exceedingly frigid planet. Pluto’s surface has ices made of nitrogen, carbon monoxide, and methane because to the extremely low temperatures.
NASA’s New Horizons: spacecraft conducted a historic flyby of Pluto in 2015, yielding the first detailed photographs and data of this far-off planet. Numerous features mentioned above were made clear by the mission, which also revolutionized our knowledge of Pluto.

Conclusion:

Because Pluto does not satisfy the International Astronomical Union’s (IAU) criteria for planetary status—namely, the need to remove other junk from its orbit—it is not regarded as a major planet in our solar system. Rather, Pluto is categorized as a dwarf planet, which is in line with its distinct features and our growing knowledge of our solar system.

Why Pluto is not a Planet? | Dwarf Planet | 2024