The news of the intergalactic visitor to our solar system, the oddly-shaped object Oumuamua, is one of the hottest subjects at the moment. At first, researchers compared it to an asteroid, but recent discoveries revealed it might actually be more similar to a comet.
Oumuamua is more comet-like than asteroid-like
Researchers discovered Oumuamua might have a core made of ice, covered in a thick layer of material made from organic components. The object passed incredibly close to the Sun, which might have led to the melting of the ice. However, it stood unaltered, meaning that the outer layer protected it.
The composition of Oumuamua indicates it’s more similar to a comet than to an asteroid. Comets are usually made of ice and rock, and asteroids of metal and rock. Also, researchers think it’s more likely for comet-like objects to travel between star systems. When our planetary system formed, the planets flung many pieces of ice beyond these boundaries.
The object looks a lot like the comets originating from our Solar System
This was the first indicative that Oumuamua was more like a comet. However, its behavior is odd, and quite different from that of a comet. It had no tail, so researchers recategorized it as an asteroid. In the end, they argued it’s more like a comet, but lacking the behavior of one. This was explained in a study in the journal Nature.
“We found that even though this object passed really quite close to our Sun — closer than Mercury — a crust like that could have insulated the interior.”
Researchers assumed Oumuamua was initially covered in ice. However, after travelling many light-years through deep space, the ice was turned into the organic material which now covers the object. This was probably the result of the cosmic rays which kept hitting it.
The composition of the material is not uniform, but most of it contains carbon signatures. This is usually associated with the presence of life, but it doesn’t mean it proves the object can sustain it. It also marks a similarity with the icy comets usually seen in our Solar System.
Image Source: Wikimedia Commons