Cloud of Oort: The secret of its creation finally cleared up?

The Oort cloud (or Oort cloud) was discovered by the Dutch astronomer Jan Hendrik Oort in the early 1950s and is a gigantic hypothetical formation of small celestial bodies. It is located about 50,000 AU (astronomical units) from the Sun, far out of the orbit of the planets and the Kuiper Belt.

Made up primarily of comets, it is a spherical unit believed to contain nearly 100 billion objects that are “the size of a mountain and sometimes larger”. The cloud is therefore extremely far from our star. In fact, the Kuiper Belt itself is a region of the solar system that extends beyond the orbit of Neptune and is between 30 and 55 times the distance between the Earth and the Sun.

A holdover from the solar system’s protoplanetary disk?

According to calculations by the US Space Agency, the inner edge of the Oort cloud would be between 2000 and 5000 AU, while the outer edge would be between 10,000 and 100,000 AU. More than 70 years after its discovery, it remains unclear how this hypothetical spherical comet set came about.

The most commonly accepted formation hypothesis is that the cloud is the remnant of the protoplanetary disk that formed around the sun about 5 billion years ago. In a new scientific article, astronomers at Leiden University in the Netherlands claim to have developed advanced computer simulations in the hope of determining where the Oort cloud was formed.

A new approach

Note that the study is currently available in a prepublication format on ArXiv. As it has already been peer-reviewed, it will appear in the journal Astronomy & Astrophysics soon. Physicists have implemented a new approach which is to take into account various events that could have occurred shortly after the universe was born.

In a statement, the astronomers claim in particular to have taken the calculations of the end of one event as the starting point for the next event. A technique that allowed them to determine that the Oort cloud is actually what was left of the protoplanetary disk that made the planets of the solar system possible.

“With our new calculations, we show that the Oort cloud emerged from a kind of cosmic conspiracy,” said astronomer Simon Portegies Zwart of the University of Leiden of the Myspaceastronomy website.

Difficult to watch

In this conspiracy, “Nearby stars, planets, and the Milky Way all play their part. Each of the individual processes alone could not explain the Oort cloud. It really takes the interaction and the right choreography of all processes together, ”adds Zwart, commenting on the university’s disagreements. Unfortunately, due to the distance between the earth and this gigantic structure, humanity may never be able to visit it.

A phenomenon that is very difficult to observe because of the distance that separates us. Photo credit: Wikipedia: From NASA This SVG image was created by Medium69 This SVG image was created by Medium69. Photo credit: William Crochot, Public Domain

Although the Voyager 1 probe can travel over a million kilometers per day, it would take another 300 years to reach the inner edge (the closest) of the Oort Cloud and 30,000 years to reach the outer edge, according to NASA. Likewise, there is still no sufficiently powerful telescope to observe the cosmic cloud. Even the James Webb Space Telescope, due to launch this year, is unlikely to see that far, said Dr. John Mather.

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