A couple of astrophysicists explained the peculiarities of Oumuamua by the fact that he is probably part of a planet similar to Pluto, but from a different solar system. Their results are published in the AGU Journal of Geophysical Research: Planets.
In 2017, the first interstellar object outside our solar system was discovered using the Pan-STARRS Astronomical Observatory in Hawaii. He was named Oumuamua, which means scout or messenger in Hawaiian. The object looked like a comet, but with features that made it difficult to classify.
Two astrophysicists from the University of Arizona, Stephen Desch and Alan Jackson from the School of Earth and Space Exploration, decided to explain Oumuamua’s strange features. They speculated that this one could be part of a Pluto-like planet from another solar system.
From observations of the object, Desch and Jackson identified several characteristics of the object that were different from what would be expected from a comet. For example, an object entered the solar system at a slightly slower speed than would be expected. This indicates that he has not traveled in interstellar space for over a billion years. In terms of size, its pancake shape is flatter than any other known object in the solar system.
In addition, the object had no detectable escaping gas, which is part of the comet’s tail. Overall, the object was very similar to a comet, but unlike any comet ever observed in the solar system.
Astronomers have hypothesized that the object is composed of different ices. They calculated how quickly these ices would sublimate (going from solid to gas) when Oumuamua passed the Sun. From there, they calculated the object’s mass and shape, as well as the reflectivity of the ice.
Based on calculations, they assumed that the ice on Oumuamua is solid nitrogen. It was he who ensured an exact match to all the characteristics of the object at the same time. And since solid nitrogen ice can be seen on Pluto’s surface, it’s possible that a comet-like object could be made of the same material.
“Oumuamua is likely a piece of the planet that was knocked off the surface by an impact about half a billion years ago and thrown out of its parent system,” Jackson concludes. “The fact that it is made of frozen nitrogen also explains the object’s unusual shape. As the outer layers of nitrogen ice evaporated, the shape of the body became more and more flat, like a bar of soap, when its outer layers were erased during use.”