Based on its speed and trajectory, Oumuamua is likely young and has been journeying between stars for only about 2 billion years.

‘Oumuamua dove down into the inner solar system from above the plane in which the planets orbit. It was visible only for a few months, speeding up as it retreated from the Sun. Based on the observed acceleration, astronomers calculated that by the time it reached the distance of Jupiter’s orbit in May 2018, ‘Oumuamua was about 62,000 miles (100,000 km) ahead of where it would be if only gravity dictated its motion. The planets are shown here as they appeared October 19, 2017.

It is thought that Oumuamua may have been ejected from its home system at high velocity, between about 6 and 16 miles (10 and 25 km) per second, and this high speed may be because it originated in a binary/trinitary star system with no large planets to assist in the acceleration. Such a system would have a hard time developing any planets at all, with most orbiters remaining small, elongated, with a somewhat "fluffy" consistency. The parent stars would have played a kind of gravitational ping-pong with their bits of debris, flinging particles in all directions.

As it departed our system Oumuamua appeared to pick up speed. It is supposed that solar wind and normal outgassing by the visitor had caused this acceleration. It was also thought that Oumuamua might be incredibly thin with a large surface area, acting as a natural solar sail. For any of this to occur, the "rock" would have to be of comet-like material, extremely porous and light, and capable of expelling approx. 2.2 pounds (1 kilogram) of material per second just as our local family of comets do. ...And if it were actually hollow, the idea of outgassing as an accelerator works quite well.

Unfortunately our infrared-seeking Spitzer Space Telescope tracked the departing visitor for 30 hours, but no outgassing was observed ... or at least there was nothing the telescope could see.

These are just my notes from reading through the astronomy.com February 2020 issue of 'Oumuamua: our first interstellar visitor.

Read through the story and see that Oumuamua was not alone. Our latest interstellar visitor is called 2I/Borisov for amateur astronomer Gennady Borisov at the MARGO observatory in Nauchnij, Crimea. 2I/Borisov had been seen moving at approx. 93,000 mph (150,000 km/h), faster than expected for an object that was still roughly 2.8 AU from the Sun. It has since crossed solar perihelion at 2 AU distance on December 8, 2019, and continued on its way outsystem, judged to remain observable by our best technologies through October of 2020.

With the 2I/Borisov event, there is a definite comet-like tail.