It is estimated to be a 800m long. An international team of researchers wrote that “we find no compelling evidence to favour an alien explanation”. “Our key finding is that ‘Oumuamua’s properties are consistent with a natural origin, and an alien explanation is unwarranted,” said University of Maryland astronomer Matthew Knight, co-leader of the research published in the Nature Astronomy. However it is not easy to fit ‘Oumuamua into familiar classifications such as a comet or asteroid. It lacked a dust tail or gas jets, characteristic of comets.
The researchers believe that a “straightforward explanation for ‘Oumuamua is that it is a planetesimal” – a planetary building block – or a fragment of one – formed in faraway star system. Now it is currently located beyond Saturn, dashing out of our solar system. We have never seen anything like ‘Oumuamua in our solar system. The only thing it really has in common with other objects in the Solar System is its reddish colouration, indicative of a dense, metal-rich composition baked by cosmic radiation.