Since August 24, 2006, Pluto fell from its category of planet in our solar system and became a dwarf planet, ceasing to be the ninth of the celestial bodies. doWhy is Pluto not a planet?? To explain this better, we invite you to read this article and find out what happened to Pluto.
Planet X
We have to go back to the mid-nineteenth century, when the astronomer Urbain Le Verrier managed to predict the location of the planet Neptune, based on some irregularities and disturbances that could be observed on the planet Uranus. In a later period, scientists inferred as a conclusion that the reason for the observed disturbances could be the existence of another planet that was exerting some influence on the orbit of Uranus and they baptized it with the name of Planet X.
Percival Lowell 1904
Near the end of the 1894th century, scientist Percival Lowell created the Lowell Observatory in Flagstaff, Arizona in XNUMX. Lowell was, in addition to being a philanthropist and amateur astronomer, a highly thoughtful and organized person. Due to those especially methodical features of his way of being, without getting tired or giving up, he was able to discover the planet Pluto. But sadly, he passed away not knowing that he had discovered it.
The method to discover planets
The methodology that is used to be able to describe celestial bodies such as the baptized Planet X or other objects that move inside taking into account How did the solar system formIt is very easy to follow, it only requires a lot of patience and perseverance. It is easy to learn that the celestial bodies that make their orbital movement around our star, the Sun, must have an apparent movement if we compare them with the stars that are in the background of the universe.
For this reason, if we manage to take spaced photographs, that is, separated by a certain period of time, directing the objective towards the same field of Stars from the bottom of the universe, it will be possible to see in them that the stars will remain fixed, while the celestial bodies that have an orbital path around the Sun, which is why they are closer to us, must move and that movement would be perceptible between photography and photography.
It is this method, with great patience, that has allowed many celestial bodies to be discovered in a sequence of photographs taken between certain periods of time, as is the case with Eris.
Flicker Microscope
But, the method is even more refined, because it is not enough to have the photographs, but they are compared in an instrument that has been called a flicker microscope. By means of this artifact two images can be observed alternately and very subtle modifications can be found. It was using this method that, on February 18, 1930, Clyde William Tombaugh managed to discover the existence of the planet Pluto.
Pluto's Volume
The volume of Pluto's mass has been subject to revision, practically since it was discovered. The first estimates were made considering the fluctuations and disturbances observed in Uranus and Neptune, reaching the point of saying in 1931 that Pluto had a volume similar to that of the Earth.
Then, in the year 1948, a new estimate reduced it to the same size as Mars. In 1975, Dale Cruikshank, Carl Pilcher, and David Morrison, scientists at the University of Hawaii, were able to calculate its albedo for the first time and found that it matched that of methane ice, concluding that Pluto had to be quite luminous and could not have more than 1% of the Earth's mass.
Then it was found that Pluto's albedo is between 1,4 to 1,9 times that of Earth, probably one of the studies that began the questioning of why is pluto not a planet
Pluto's discoverer
Clyde W. Tombaugh in 1930 was a young researcher, who was entrusted with the assignment of trying to find the celestial body that had been baptized as Planet X. In order to carry out the task assigned to him, he had at his hand a 13-inch astrograph, with which photographs could be taken of the same section of the heavens but several days apart. Later, he analyzed the images obtained by means of the flicker microscope.
In this way, Tombaugh was able to do a comparison experiment between his photographs and the images that Lowell had obtained and was able to conclude that Lowell had already managed to obtain images of Pluto.
Pluto's first planetary days
The days when Pluto was considered a planet are still fondly remembered. For many decades it was very estimative because it was the smallest planet in our solar system and also the one that was farthest from the sun. Its size is only half the width of a nation like the United States of America and it is located in a very remote area of the solar system that has been called the Kuiper Belt, making it necessary to use a telescope to observe it.
Another reason why it was held in such esteem was that it was the only planet ever discovered by an observatory located in the United States.
Its discovery dates back to the year 1930, when the astronomer Clyde Tombaugh, at the Lowell Observatory in Arizona, which received that name in honor of the respected American astronomer Percival Lowell, who founded it, although this scientist believed that the Martians dug the channels found in the Pluto's surface. Although Tombaugh concluded that the true discoverer had been Lowell.
Its enormous distance from the Sun and Earth, together with its small size, prevent it from shining beyond the 13,8 magnitude scale when it is at its best perihelion position, which is why it can only be observed through telescopes, from 200 mm aperture, photographically or with a CCD camera. Another argument from Why is Pluto not a planet?
Even in those good moments it appears to us as a punctual star that has a stellar appearance, a faded yellow, without special or distinctive features, although its apparent diameter is less than 0,1 seconds of arc. It was necessary to wait until 2015, at which time the New Horizons space probe passed over Pluto on its path and scientists were allowed to clearly appreciate its true appearance for the first time.
Pluto's name
Of course, the discovery of a new planet within our solar system was great news, which traveled the entire world at great speed and all astronomers and amateurs began to send name proposals to Lowell Observatory, among which was Pluto.
On March 14, 1930, Falconer Madan, who was a librarian at the Oxford University Bodleian Library, told his granddaughter Venetia Burney about the find and she suggested the name Pluto, which was in Roman mythology the god of the underworld.
The story behind Pluto's name is also famous.
It was proposed by an 11-year-old girl, Venetia Burney, who lived in England, and was interested in Roman mythology and had the idea to name this new frozen planet after the intriguing god of the underworld. Her grandfather took the suggestion to a member of the UK's Royal Astronomical Society, who passed it on to her American colleagues at Lowell Observatory.
The newly discovered planet, whose orbit extends more than 4.828 million kilometers from the sun, would also be known as the King of the Kuiper Belt.
Voting and its reasons
With all the proposals received, a vote had to be held at the Lowell Observatory to choose between Minerva, Cronos and Pluto. Finally, the name Pluto received all the votes, among other reasons, because the first two letters of the name (PL) coincided with the initials of its founder, Mr. Percival Lowell. For that reason too, the symbol for this planet is a P and an L.
Pluto as a dwarf planet and the IAU definition
But on August 24, 2006, the International Astronomical Union redefined the concept of what should be understood as a Planet. This led to consider Why is Pluto not a planet? From that moment on, for a celestial object to be classified as a planet, it must meet the following requirements:
Being a celestial body that is in orbital motion around the Sun.
Having enough mass so that the gravitational force emanating from it overcomes the force of a rigid body so that it comes to adopt a hydrostatic equilibrium, with the shape of a sphere.
It must have managed to sweep the adjacencies of its orbit of objects.
It turns out that Pluto meets all the requirements, except the third, which is why it fell from its position as the ninth planet of the solar system, to be considered today within the category of the Tiny planets.
What does Pluto look like?
The mission of the New Horizons space probe took about 9 years and had to travel more than 3.000 million kilometers to reach Pluto, where it collected fundamental data, information and many images, which according to scientists were going to explain Why is Pluto not a planet?
In high-resolution images, which could be taken by NASA's New Horizons spacecraft, it can be seen that the surface of Pluto enjoys a remarkable range of subtle colors. These new images of Pluto have stunned planetary researchers because the small world's atmosphere, backlit by the sun, has been photographed.
When NASA managed to publish the clearest images that had been obtained so far of the surface of Pluto, it was possible to observe that they exhibited a mountainous coast of what is known as Sputnik Planum, being able to be seen in a very beautiful way the mountains that border it.
Craters
It was also possible to observe that Pluto had many craters, in particular one that is about 250 kilometers wide, also showing signs that erosion and fault systems that may be of geological origin have managed to detail Pluto's surface, turning it into rough land. and wastelands.
It has been possible to discover that the largest satellite of Pluto is the moon Charón, which has been photographed thanks to the blue, red and infrared contrasts of the New Horizons probe equipment, on July 14, 2015, being able to determine which ones are its characteristics, which are very different from those shown on the surface of the planet.
Area
Another of the characteristics of Pluto that could be observed in the images taken by the New Horizons space probe is the variety of textures that its surface presents, including what NASA has called mountains that have been molded with very strange textures. These mountains are usually informally referred to as Tartarus Dorsa.
It has also been possible to observe in these images that Pluto has large glacial plains, which have been nicknamed Sputnik Planum. In this regard, the researchers have said that what appears as mountains in the photographs could actually be immense groups of frozen water, which are suspended above frozen nitrogen.
These are some of the conclusions that have been reached after examining the images taken when the probe passed closest to the surface of Pluto, at about 80.467 km from it, on July 14, 2015.
The truth is that it has been possible to conjecture that there is a lot of variety on the surface of this planet. Plains, mountains, craters and what could apparently be dunes. The smallest details in the images are about 0.8 kilometers wide. It has also been concluded that the area of the craters is ancient, although the area of the flat frozen plains is of recent date, according to the scientists.
Satellites
Not only could Charon be photographed, but also images of Charon, which is the largest satellite orbiting Pluto, could be obtained, finding that Charon's north pole area is extremely dark and has a chain of chasms deeper than the Grand Canyon, in Colorado.
Another revelation of the photographs taken by the New Horizons space probe is that Pluto has a formation that looks like a heart, and has been temporarily baptized with the name of Tombaugh Regio, where a large area of plains without craters can be seen It seems to date back to barely 100 million years old. It was also a huge surprise for scientists to see that near Pluto's equator there is a young mountain range.
Thanks to the fact that an analysis of spectra could be carried out using the Ralph apparatus of New Horizons, it has been possible to establish that there is a large amount of methane ice on Pluto, although with great disparities from one place to another on the frozen surface of Pluto. .
And then there were eight
The path was twisted for Pluto in 2006, when the IAU redefined the concept and the characteristics that a celestial body must have to be considered as a planet and the reason why Pluto did not meet the requirements is that its Óorbit overlaps that of the planet Neptune.
For this reason, the IAU reclassified it as a dwarf planet, but also baptized it as a trans-Neptunian object, which was considered derogatory and brought with it the ire of fans of small planets and the internet in general.
Start of the Discussion
For many space fans, Why is Pluto not a planet? or the degradation to which Pluto was subjected took them by surprise. But in scientific circles in the astronomical academic world, it was a debate that began only a few decades after the dwarf planet was discovered.
As early as 1992, staff astronomers at the University of Hawaii observatory on Mauna Kea discovered the existence of a small icy celestial body located a little further from the orbit of Neptune. It was named the 1992 QBI Kuiper Belt Object, and its discovery led to the thought that Pluto might be just one of many planet-like objects found in the Kuiper Belt, that is, Why is Pluto not a planet?
But the crushing blow came in 2003, when California Institute of Technology professor Mike Brown managed to discover Eris, a dwarf planet that actually has a little more mass than Pluto. Because of this, scientists and astronomers began to speculate that it was possible that there were more of these small celestial bodies orbiting in space, why is pluto not a planet individually considered.
Because of his discovery, Mr. Brown is known today as the man who killed Pluto, because instead of recognizing Eris and all celestial bodies larger than Pluto as a planet, the IAU came to the decision to declassify Pluto as a planet and convert it into a planetoid or dwarf planet.
New Horizons relaunches the old debate
But with the information that was obtained thanks to the images and experiments carried out by the New Horizons space probe, the discussion about the reclassification of Pluto continues. One of the conclusions that could be reached in 2015, due to the results of research carried out at NASA, is that it was revealed that Pluto has a greater volume than scientists originally thought, although it supports the thesis of Why is Pluto not a planet?
NASA also concluded that, according to the information that has been collected by the New Horizons probe, Pluto and its satellites are much more complex than could have been imagined, all of which made the scientific worlds, scholars and laymen alike speculated whether Pluto could regain its status as a planet.
Planetary Scientist Opinions
Even a researcher of the stature of Alan Stern expressed his disagreement with the decision adopted by the IAU, stating that the reason why Pluto was demoted from its status as a planet, that is, the reason Why is Pluto not a planet? It was because of its great distance from the Sun.
He went further, when he stated that if an analysis of images of the Earth located in a hypothetical position equal to or similar to that of Pluto, with respect to the Sun, could be made, the Earth would also be excluded from the solar system.
In 2014, the Harvard-Smithsonian Center for Astrophysics was also involved in the controversy. After a meeting of experts regarding the definition of a planet, the audience was allowed to vote, and, as expected, the attendees gave their support to the planet Pluto, against the theory of Why is Pluto not a planet?
On the other hand, at the Space Institute of the University of Central Florida, a new investigation was started based on the argument that the degradation of Pluto to a dwarf planet by the IAU could not be considered valid.
In a statement, planetary scientist Philip Metzger opined that the IAU concept, in theory, should be oriented towards an essential goal, which is planetary science, but the concept of a planet that exists is one that no one uses in their research. He said this because Metzger and his team did an analysis of more than 200 years of research and found only one study that used the standard orbit-cleaning concept that the IAU used to downgrade Pluto.
This led him to also state that the IAU's new definition is sloppy, with Metzger later adding that the IAU did not explain what they meant by their third requirement, that is, what it means to clear your orbit. He asserted the scientist that if that requirement is taken literally, then there would be no planets of the solar system, because no planet performs the function of clearing its orbit.
too cool for school
From the moment that Pluto descended from its category of planet, that is, since it was explained Why is Pluto not a planet? difficulties and problems began, not only in the scientific field. In fact, no one was prepared for the impact that degradation caused.
In the academic field it caused quite a stir, and we are not referring to scientific theories and experiments, but to something more basic, because in the first place it caused a wave of reprints of science textbooks, in which it is explained to the students of this new millennium that Pluto is a dwarf planet.
However, Pluto has been shown to be the most interesting non-planet to learn about planetary composition, literally speaking.
It has been shown, thanks to the voyage of the New Horizons probe, that Pluto has an extensive ice sheet, dunes that are made of solid methane ice, and peaks and mountains covered in methane snow, but due to its composition, snow is red (instead of being fluffy white). Another shocking discovery is that Pluto has the largest known glacier in the solar system.
In fact, Pluto has such extreme cold temperatures, it's about minus 204,4 degrees Celsius, and that temperature drops further as its orbit takes it farther from the sun, i.e. in his aphelion. In general, Pluto is so far from the Sun that the light of a day on Pluto resembles that cast by a full moon at night on Earth.
If we observe it from the surface of Pluto, the Sun will simply appear to us as a bright star. It may be that the reason scientists and fans remain intrigued by Pluto's recategorization 14 years later is its undeniable coolness.
Planetary scientist Alan Stern said in a statement released by NASA that the newfound complexity of Pluto's system, from its geological composition to its system of moons and atmosphere, has always been beyond even our wildest dreams. this scientist, should be enough to throw back the theory of why is pluto not a planet. And he concluded by saying that in all the places to which it has been possible to turn we find that there are new mysteries.
