Final answer:
An interstellar object named 'Oumuamua was discovered in 2017 with a highly unusual hyperbolic orbit and elongated shape. It was a significant find because it did not match the characteristics of asteroids typically found in the asteroid belt between Mars and Jupiter, which have nearly circular or elliptical orbits and more rounded shapes.
Step-by-step explanation:
In late 2017, an object named 'Oumuamua was discovered and initially categorized as an interstellar asteroid due to its high velocity and hyperbolic orbit, which indicated it was not gravitationally bound to the Sun. This discovery was made using a survey telescope located on Haleakala, Hawaii. Unlike most asteroids in the solar system that revolve around the Sun in nearly circular or elliptical orbits and are found within the asteroid belt between Mars and Jupiter, 'Oumuamua's path was distinctly different. 'Oumuamua, with its elongated and cylindrical shape, measuring approximately 200 meters in length and only 35 meters wide, displayed an extreme shape ratio unlike typical asteroid or comet bodies, whose shapes are often rounded or 'potato-like' due to their gravity.
Asteroids tend to revolve about the Sun in the same direction as the planets and are usually found near the plane in which Earth and other planets orbit. The discovery of 'Oumuamua was significant not just because it was the first known interstellar visitor to our solar system, but because it challenged our understanding of the formation and composition of such objects. Through the history of asteroid exploration, starting with Giovanni Piazzi's discovery of Ceres in 1801, astronomers have continually refined our knowledge about these celestial bodies, including their orbits which are usually stable over short periods but can become unpredictable over longer times due to gravitational interactions with planets, potentially leading to collisions with Earth or ejection from the solar system.