On October 14, 2017, an object from interstellar space entered our solar system. Four days later, it appeared on one of Earth’s telescopes — the University of Hawaii’s Pan-STARRS1 telescope, funded by NASA’s Near-Earth Object Observations Program. It was initially classified as an asteroid, but this classification was altered after it was found the object was accelerating, like a comet. ‘Oumuamua is estimated to be one-quarter of a mile long, and approximately ten times as wide. It is the largest comet or asteroid ever observed in our solar system. Moreover, its elongated shape is something that scientists have only seen rarely, and could potentially provide clues as to how the universe formed.
The observations indicated to scientists that the object had been traveling through the Milky Way, unattached to any star system for hundreds of millions of years. The prospect of observing an interstellar object incited an international effort to see it more clearly. Telescopes throughout the world were utilized to discover the object’s color, brightness, and orbit. Their observations further confirmed the theory that the comet was interstellar in origin. Telescopes in space, like NASA’s Hubble, tracked the object, finding its speed was about 85,700 miles per hour. Scientists discovered its potential point of origin, near the star Vega. However, they found that the position of the stars had greatly changed since ‘Oumuamua had been there 300,000 years ago.
Although most scientists agree that ‘Oumuamua is interstellar, some suspect that it is alien (from another planet) instead.
‘Oumuamua continues to pass through and out of the solar system. At this point, all the data that can ever be collected from it has been recorded. It is now up to scientists to piece together a coherent story about the universe and the flying objects that glide through it.
Fun Fact: ‘Oumuamua derives its name from the Hawaiian meaning “a messenger from afar arriving first.”
Image Credit: European Southern Observatory