Solar system: What are Trans-Neptunian objects?

In the mid-1930s, American astronomer Clyde Tombaugh discovered the existence of the planet Pluto; a few decades later this planet was reclassified as a “dwarf planet”. For a long time, scientists believed that this celestial body was the only celestial body beyond the orbit of Neptune; It is not surprising that Pluto is considered the largest trans-Neptunian object in terms of radius, but not the largest among them.

Generally, When astronomers use the term ‘Trans-Neptunian planet’ they are talking about a dwarf planet beyond Neptune It does not meet all the criteria to be a planet. For example, Neptune is considered a ‘trans-Neptunian planet’, but does not meet all classifications as a planet.

However, the term ‘Trans-Neptunian planet’ is not entirely accurate as it is used unofficially to describe the existence of a planet beyond Neptune. The correct term is Trans-Neptunian object (TNO), as astronomers have not found planets beyond just Neptune.; These are some objects with certain properties.

To explain a little more about what trans-Neptunian objects are, TecMundo gathered information from scientists and experts in the field.

What are Trans-Neptunian objects?

Trans-Neptunian objects, abbreviated as TNOs It is classified as any cosmic object orbiting the Solar System but farther than the average distance to Neptune. TNOs are on average about 30 Astronomical Units (AU) away from the Sun, i.e. 4.488 billion kilometers. Because they are at great distances, the Sun cannot illuminate or ‘heat’ the area as it can with other planets; Therefore, it is considered a dark and extremely cold part of the universe.

Because they are so far from the Sun, astronomers observe TNOs as small points of light; In many cases, they appear a dull red color, such as when viewing Pluto. Scientists have already discovered nearly three thousand trans-Neptunian objectsBut they believe there are thousands more ‘missing’ people who need to be identified.

“The largest trans-Neptunian objects (TNOs) represent an extremely diverse collection of early objects in the outer solar system. Although the community often calls these objects “dwarf planets (Dps),” the International Astronomical Union (IAU) officially recognizes only four planets. knows. [planetas] TNOs such as Pluto, Eris, Makemake and Haumea are described in an article in the journal Science.

Right now, Eris is considered the largest trans-Neptunian object ever discovered; It is 38 times farther from the Earth at its closest point to the Sun, and up to 100 times farther away from the Sun.

Kuiper Belt

Most trans-Neptunized objects discovered by astronomers are located in the Kuiper Belt, a region of the solar system that extends up to 50 AU from the Sun. For example, the dwarf planets Pluto, Eris, Makemake, and Haumea are located on the Sun. Kuiper Belt; but it is likely that there are thousands of other TNOs spread across the region.

The region was discovered by Dutch astronomer and professor Gerard Kuiper when he published a scientific paper theorizing the possibility of the existence of other cosmic objects besides Pluto. Even if, some scientists call these Kuiper belt objects (KBOs), but the term trans-Neptunian object (TNOs) is much more commonly used in the scientific community.

“Astronomers believe that icy Kuiper Belt objects are remnants left over from the formation of the solar system. Similar to the relationship between the main asteroid belt and Jupiter, it is a region of objects that would come together to form a planet if Neptune did not exist. Instead, Neptune’s gravity forces this region of space to “It shook so much that the small icy objects there could not come together to form a large planet.” NASA explains in an official publication:

Generally, TNOs identified in the Kuiper Belt are known for their more divergent orbits, possibly due to gravitational effects. It is one of the giant planets in the region, like Neptune itself. In fact, despite the small number of TNOs observed, astronomers suggest that there are hundreds of thousands of objects 100 kilometers or larger across the region.

In any case, there is a great diversity among trans-Neptunian objects with different sizes, shapes and colors. They are also not evenly distributed in space, as they can be grouped according to the shape and size of their orbits.

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