Most of the classical bodies belong to this population. The orbits of hot classical KBOs are more elliptical and tilted. Since their orbits are elongated, there will be times when they will be closer to the Sun.
In some parts of their orbits, they will also be farther. In contrast, the cold classical KBOs never came close to the giant planet. Because of that, their orbits remain unperturbed. Resonant KBOs have orbits that are in a stable and repeating pattern with Neptune. That means, for every specific number of orbits they complete, Neptune also completes a specific number.
This is more like a ratio. For example, Pluto is in a resonance with Neptune. That means it completes 2 orbits around the Sun for every 3 orbits that Neptune makes. Aside from that, there are also other resonances like , , and These numbers can also be written the other way, like for Neptune and Pluto. Since the trans-Neptunian objects have longer orbital periods than Neptune, the smaller number corresponds to them.
Just like Pluto, many objects are also in the same resonance with Neptune. Because of that, the category Plutinos was made.
Most resonant objects are in this category. As of February , there are already confirmed plutinos. The discovery of one KBO can lead to a better understanding of the others. There are so many of these objects but below are some of the famous ones.
Pluto was once the ninth planet in our solar system. It was the first KBO to be discovered. Pluto is the largest dwarf planet, but only second to Eris when it comes to mass. It lies around 40 AU from the Sun. A year in this distant world takes roughly Earth years. However, a day there is only about 6 hours long. Pluto is 5. It is also smaller than our Moon. One of its most distinguishing features is the heart-shaped glacier called Tombaugh Regio.
This feature is roughly the size of Texas and Oklahoma. Pluto has blue skies, high mountains, and a thin atmosphere. It also snows there, but instead of white, they are red in color. Makemake is another dwarf planet in the Kuiper belt. It is located about 45 AU from the Sun. At that distance, it takes sunlight 6 hours and 20 minutes to reach it. Makemake was discovered in Together with Eris, it is one of the reasons for the creation of the dwarf planet category.
Also, it has a provisional moon nicknamed MK2. Haumea is a uniquely shaped dwarf planet in the Kuiper belt. It is about the same size as Pluto. Since it rotates very fast, its shape has become distorted and it now looks like an egg. Its discovery was rather controversial because two teams claimed credit for discovering it. Haumea lies 43 AU from the Sun. It rotates every 4 hours, making it one of the fastest-spinning large bodies in the solar system.
A year in Haumea is equivalent to about years on Earth. Quaoar is a planetoid in the Kuiper belt. Discovered in , this object is roughly 1, km mi across. Years later, objects bigger than Quaoar were discovered like Eris and Haumea. Quaoar follows a nearly circular orbit and it is not in resonance with Neptune. In , a moon around it was discovered. This natural satellite is named Weywot. Orcus is a plutino, which means it is in a resonance with Neptune, just like Pluto.
It was discovered in , though the earliest precovery images can be traced back to It is located roughly 39 AU from the Sun and completes an orbit in years. Orcus has a large moon called Vanth. This natural satellite is half the size of Orcus. In fact, it is the third-largest moon beyond Neptune. The first two are Charon Pluto and Dysnomia Eris.
Arrokoth is KBO that looks like a snowman. This object is important in the history of space exploration. So far, it is the farthest and the oldest object in the solar system that was visited by a man-made spacecraft. According to one well-supported theory known as the Nice Model, as in Nice, France , the shifting orbits of the four giant planets Jupiter, Saturn, Uranus and Neptune could have caused most of the original material — likely 7 to 10 times the mass of Earth — to be lost.
Today the Kuiper Belt is slowly eroding itself away. Objects there occasionally collide, with the collisional fragments producing smaller KBOs some of which may become comets , as well as dust that's blown out of the solar system by the solar wind. The total mass of all the material in the Kuiper Belt today is estimated to be no more than about 10 percent of the mass of Earth. A fairly large number of KBOs either have moons — that is, significantly smaller bodies that orbit them — or are binary objects.
Binaries are pairs of objects that are relatively similar in size or mass that orbit around a point a shared center of mass that lies between them. Some binaries actually touch, creating a sort of peanut shape, creating what's known as a contact binary. The Kuiper Belt is a source of comets, as it very slowly erodes itself away.
Pieces produced by colliding KBOs can be pushed by Neptune's gravity into orbits that send them sunward, where Jupiter's gravity further corrals them into short loops lasting 20 years or less. These are called short-period Jupiter-family comets. Given their frequent trips into the inner solar system, most tend to exhaust their volatile ices fairly quickly and eventually become dormant, or dead, comets with little or no detectable activity.
Researchers have found that some near-Earth asteroids are actually burned-out comets, and most of them would have started out in the Kuiper Belt. Sedna is about 1, miles 1, km wide and circles the sun on an eccentric orbit that ranges between 8 billion miles In July , astronomers announced the discovery of an object in the Kuiper Belt thought to be larger than Pluto, though subsequent observations revealed it was slightly smaller.
Known as Eris , it orbits the sun approximately once every years, traveling almost one hundred times farther from the sun than Earth does. Eris' discovery revealed to some astronomers the problem of terming Pluto a full-scale planet, and in , Pluto, Eris, and the largest asteroid, Ceres , were reclassified as dwarf planets.
Two more dwarf planets, Haumea and Makemake , were discovered in the Kuiper Belt in But Haumea's status as a dwarf planet may be in doubt. In , when the object passed between Earth and a bright star, scientists realized it is more elongated than round. Roundness is one of the criteria of a dwarf planet, according to the International Astronomical Union's definition. Haumea's fast spin may be responsible for its elongated shape; a day only lasts about four hours.
The dwarf planet was already known to have moons, but Sanz and his team also found rings around it. Planet Nine is a hypothetical world thought to orbit the sun at a distance that is 20 times farther out than the orbit of Neptune.
The orbit of Neptune is 2. The strange world's orbit is about times farther from the sun than the Earth's orbit is from the star. Scientists have not actually seen Planet Nine directly. They are dwarf planets like Pluto. Kuiper Belt. The Latest. Several dwarf planets within the Kuiper Belt have moons. JPL's lucky peanuts are an unofficial tradition at big mission events. A spacecraft has sent back pictures of the sky from so far away that some stars appear to be in different positions than we'd see from Earth.
The farthest object ever explored is slowly revealing its secrets, as scientists piece together the puzzles of the Kuiper Belt object NASA's New Horizons spacecraft flew past on New Year's Day, four billion miles from Earth.
A Prehistoric Puzzle in the Kuiper Belt. Meet the women leading two of humankind's two most distant space missions. Women at the Helm. The highest resolution images offer about feet 33 meters per pixel. New Horizons Flyby: Where to Watch. Closest approach takes place in the early morning hours of New Year's Day— a.
0コメント