In the vast universe, the earth is eye-catching for its unique existence of life. This blue planet has nurtured countless life forms, from strange creatures in the deep sea to huge beasts on land, to humans who can think and explore. The diversity of life is amazing. And when we cast our eyes to the depths of the universe, a story about Pluto, a dwarf planet on the edge of the solar system, gradually emerges before our eyes.

Pluto, a celestial body once regarded as the ninth planet in the solar system, has undergone earth-shaking changes in its fate in scientific exploration. In 1930, American astronomer Clyde Tombaugh first discovered Pluto. Due to the limitations of observation technology at the time, scientists mistakenly believed that its mass was similar to that of the earth, so they included it in the ranks of planets. However, with the continuous advancement of observation technology, the true face of Pluto gradually emerged: its diameter is only 2,376 kilometers, and its mass is only 0.22% of the Earth, even smaller than our moon. This discovery triggered a re-examination of the definition of planets in the scientific community. Finally, in 2006, Pluto was officially removed from the ranks of planets and downgraded to a dwarf planet.

Despite losing its planetary status, Pluto still attracts the attention of scientists with its mysterious appearance. In order to uncover the secrets of this distant dwarf planet, the National Aeronautics and Space Administration (NASA) launched the New Horizons probe. After a long journey of 9 and a half years, New Horizons successfully flew over Pluto and its satellites in 2015, taking a series of high-definition photos that revealed the mystery of Pluto. Pluto is located in the Kuiper Belt, the outermost part of the solar system. It is a celestial body composed of ice and rock. Its surface temperature is extremely low, about minus 230 degrees Celsius, and it is covered with substances such as ice, methane and carbon monoxide.

Pluto has many amazing and unusual features. First, because it is extremely far from the sun, the sun on Pluto looks like a tiny star with very low brightness. On Pluto, the sun's light takes 5 and a half hours to reach, making the sky here look particularly dim. Secondly, Pluto's atmosphere changes as it moves away from the sun. When Pluto is far away from the sun, the nitrogen, methane and carbon monoxide in its atmosphere condense into frost and snow and fall to the surface, causing the atmosphere to disappear temporarily; and when Pluto is close to the sun, these gases evaporate again to form an atmosphere.

Pluto also has a giant satellite called "Charon". Although Charon's diameter is smaller than the moon, due to its extremely close distance to Pluto, Charon's diameter on Pluto looks nearly 7 times that of the full moon. This spectacular scene cannot be seen on Earth. Pluto's orbit is also very special, presenting a very large ellipse. This orbit makes it possible for Pluto to collide with other celestial bodies, and even with Neptune. Scientists speculate that the anomaly in Pluto's orbit may be related to a star called Schultz's Star that broke into the solar system 70,000 years ago.

Pluto's surface topography is equally amazing. It is covered with canyons, craters and mountains, some of which are taller than any mountain humans have ever climbed. Pluto's surface seems to be withered, because its atmosphere is not thick enough to protect the surface from the damage of solar radiation. Pluto's surface is also covered with a large number of glaciers and icebergs, which are covered by a thin layer of dust, making the surface appear darker. Pluto's heart is one of the most striking features on its surface. It is a bilaterally symmetrical area composed of cold nitrogen methane and some rocks, surrounded by a layer of mist, as if covered with a mysterious veil.

Although humans still have very limited knowledge of Pluto, scientists have never stopped exploring. With the continuous development of science and technology, humans will have a deeper understanding of Pluto. The story of Pluto is not only the exploration of a dwarf planet at the edge of the solar system, but also a symbol of mankind's endless curiosity and pursuit of the unknown world.