The asteroid 'Oumuamua gained significant attention and sparked scientific curiosity due to several peculiar characteristics that set it apart from typical asteroids:
Interstellar origin: 'Oumuamua is the first known object to have entered our solar system from interstellar space. Its trajectory and velocity indicated that it originated from outside our solar system, making it an interstellar visitor.
Unusual shape: Unlike most asteroids that are roughly spherical or irregularly shaped, 'Oumuamua has an elongated, cigar-like shape. It is estimated to be approximately 800 meters long and 80 meters wide, making it highly elongated compared to any known solar system object.
Rapid rotation: Observations revealed that 'Oumuamua was spinning or tumbling rapidly as it traveled through space. This rapid rotation made it challenging to obtain detailed observations and measurements of its surface features.
Non-gravitational acceleration: Astronomers noticed that 'Oumuamua displayed a small but significant acceleration in its trajectory that could not be solely accounted for by the gravitational forces from the Sun and planets. This unusual acceleration, referred to as a non-gravitational or excess acceleration, sparked speculation about possible explanations, including the influence of cometary outgassing or solar radiation pressure.
Reflectivity and color: 'Oumuamua exhibited unusual reflectivity and color properties. Its surface appeared to be highly reflective, similar to shiny metal, and it had a reddish hue. These characteristics were distinct from most objects in our solar system.
Short visit: 'Oumuamua passed relatively close to the Sun and Earth, allowing scientists to observe it for a limited period before it moved out of range of telescopes. Its swift journey through our solar system and its interstellar origin made it a fleeting and unique object of study.
Due to these extraordinary features and its fleeting visit, 'Oumuamua generated significant interest among astronomers and led to numerous scientific studies and speculations about its origin, composition, and nature. However, since 'Oumuamua was only observed from a distance, its true nature and origin remain a subject of debate and speculation, and no definitive conclusions have been reached.