Centaurs

I thought this article at Mysterious Universe was interesting:
https://mysteriousuniverse.org/2018/11/a...ar-system/

It seems there are these things called centaurs which have unstable orbits between Jupiter and Neptune and are something between comets and asteroids (as centaurs in Greek mythology were between humans and horses).
https://en.wikipedia.org/wiki/Centaur_(minor_planet)

Now it's being suggested that a substantial number of centaurs came from outside the solar system (like 'Oumuamua, the object that recently created something of a stir) and were captured because of the gravitational pull of Jupiter, and that hundreds of these would be easily identifiable from their orbits. (The MU article seems to suggest all centaurs have retrograde orbits, but according to Wikipedia only a small percentage do.) According to the Harvard professor Abraham Loeb, these would be "perfect candidates for a space mission".

However, Loeb does perhaps have a vested interest in exciting public enthusiasm for space missions, as he chairs the advisory board of "Breakthrough Starshot", which is trying to develop a spacecraft propelled by a light sail. It was Loeb who suggested that 'Oumuamua could be a light sail because of its anomalous trajectory.

Courtesy of the Daily Grail, here's a further comment by Loeb in Scientific American. It's about 'Oumuamua and the Centaurs, though his thoughts about the reaction in some quarters to the 'Oumuamua problem are relevant to other areas as well:

My past experience taught me not to rely on gut feelings in situations like this, because gut feeling is guided by prejudice (labeled by Bayesian statisticians as the “prior probability”). And prejudice is shaped by experience, so we bring the risk of missing unexpected discoveries if we always expect the future to resemble the past.

Some social media aficionados declared with great confidence that ‘Oumuamua is not artificial in origin. But they did not provide evidence to support their claim. They argued along the lines that “there are things we do not understand, which are nevertheless thought to originate from natural causes.”

https://blogs.scientificamerican.com/obs...-oumuamua/