The interstellar object that visited our solar system in the year 2017, caused a stir in the scientific community regarding its formation and where it came from? What is Oumuamua? The celestial rock has created a significant buzz in the scientific community from the time it made its appearance in the year 2017. At first, it was believed that it was a comet, but later ESO announced that the observation and measurement of this celestial object matched to an asteroid, and there was a lot of stir because of it, as it was the first asteroid known to mankind that came from interstellar space. It was named Oumuamua which loosely translates to something that is a messenger or a scout from the past. So, where did Oumuamua come from? Scientists are toying with various possibilities that could explain its existence and where it came from? They have broadly narrowed down four stars that could have come from. These stars are HD 292249 which resembles our sun, a red dwarf star HIP 3757, and two unnamed stars. The findings suggested that Oumuamua had something to do with these stars or had a close encounter with them. Let’s have a look at some of the popular theories about the formation of Oumuamua. It is an alien spacecraft that is sent to investigate our home planet earth The biggest and the most popular theory regarding Oumuamua is that it is an alien spacecraft that has come to know more about the earth and probably earthlings. The researchers at the Harvard Smithsonian Center of Astrophysics believe that it is of an artificial origin because it is a light sail and a piece of advanced technological equipment flowing through the interstellar universe. Something like our Voyager 1 and Voyager 2.  Theory number two suggests that Oumuamua is a comet Another group of astrophysicists believes that Oumuamua is a comet as its rock is accelerating which is common in most comets. But if we believe our data then comets also have a trail of gas that helps them push through the universe, something like our rockets. But astronomers are of the belief that maybe we just missed it or is too hard to detect. They further explain that it might contain different materials which explain the absence of the gas tail. Even though it was the first interstellar rock that mankind witnessed and it leave us with any questions. Maybe the next alien celestial object gives us more answers than questions.