Kuiper Belt

Since, the discovery of Pluto the Trans-Neptunianregion, also called as Edgeworth-Kuiper belt,  of our solar system was attracting scientists all around the world. Edgeworth-Kuiper belt, is similar to the asteroid belt although far more larger than the asteroid belt, it mainly contains the remnants of the solar system. The classical belt is residence of three dwarf planets –PLUTO, HAUMEA and MAKEMAKE.

Kuiper belt extends from the orbit of Neptune (at 30 AU) to approximately 50 AU from the Sun. “Triton” Neptune’s moon is also known to be originated from the Kuiper belt region; lots of studies over the topic have shown that the belt is dynamically stable. Pluto is the largest known member of the Kuiper belt, if the scattered disc is excluded .Often Kuiper belt is confused with the Oort-Cloud but reality is that Oort cloud is thousand times more distant than the belt is.Fredrick.c.leonard was the first person to suggest regarding the region .But, it was in 1951 Gerard Kuiper achieved a major breakthrough in the research.Later as the evolution takes place a hypothesis were proposed.

 The famous "dirty snowball" hypothesis for cometary structure thought that a "comet belt" might be massive enough to cause the purported discrepancies in the orbit of Uranus that had sparked the search for Planet X or at the very least, to affect the orbits of known comets. Observation, however, ruled out this hypothesis.

In 1977, Charles Kowal discovered 2060 Chiron, an icy planetoid with an orbit between Saturn and Uranus. He used a blink comparator; the same device that had allowed Clyde Tombaugh to discover Pluto nearly 50 years before. In 1992, another object, 5145 Pholus, was discovered in a similar orbit. Today, an entire population of comet-like bodies, the centaurs, is known to exist in the region between Jupiter and Neptune. The centaurs' orbits are unstable and have dynamical lifetimes of a few million years. From the time of Chiron's discovery, astronomers speculated that they therefore must be frequently replenished by some outer reservoir.

Further evidence for the belt's existence later emerged from the study of comets.It was in 1987 that puzzled by the emptiness of outer space scientists around the world started finding and vigorous research regarding the region particularly in US. Through studies a final hypothesis was proposed that the scattered disc was created when Neptune migrated outward into the proto-Kuiper belt, which at the time was much closer to the Sun, and left in its wake a population of dynamically stable objects which could never be affected by its orbit (the Kuiper belt proper), and a population whose perihelia are close enough that Neptune can still disturb them as it travels around the Sun (the scattered disc). Because the scattered disc is dynamically active and the Kuiper belt relatively dynamically stable, the scattered disc is now seen as the most likely point of origin for periodic comets.

The size structure and mas of Kuiper Belt was further found out and it was recorded that at its fullest extent, including its outlying regions, the Kuiper belt stretches from roughly 30 to 55 AU. However, the main body of the belt is generally accepted to extend from the 2:3 resonance at 39.5 AU to the 1:2 resonance at roughly 48 AU. The Kuiper belt is quite thick, with the main concentration extending as much as ten degrees outside the ecliptic plane and a more diffuse distribution of objects extending several times farther. Overall it more resembles a torus or doughnut than a belt. Its mean position is inclined to the ecliptic by 1.86 degrees.

The presence of Neptune has a profound effect on the Kuiper belt's structure due to orbital resonances. Over a timescale comparable to the age of the Solar System, Neptune's gravity destabilizes the orbits of any objects which happen to lie in certain regions, and either sends them into the inner Solar System or out into the scattered disc or interstellar space. This causes the Kuiper belt to possess pronounced gaps in its current layout, similar to the Kirkwood gaps in the asteroid belt.

The number and variety of prior speculations on the nature of the Kuiper belt have led to continued uncertainty as to who deserves credit for first proposing it. But, still it continues to be discovered through and remains a topic of debate.

-RUTURAJ BARGAL