> “The more I study this object, the more unusual it appears, making me wonder whether it might be an artificially made probe which was sent by an alien civilization,” Avi Loeb, the chair of Harvard’s astronomy department and one of Milner’s advisers on Breakthrough Listen, wrote in the email to Milner.

It may sound silly, but I find it fascinating that we're finally in a time when someone in such high position in science can say such a thing without fearing ridicule. I'm also grateful that there are people wealthy enough to sponsor these scientific efforts. What an amazing time!

I think he's bat-shit insane to make a mildly qualified statement like that.

Why do you think he doesn't fear or risk ridicule by this statement.

If we detected radio signals I'd be all for a crash project to do so, possibly using NERVA or some similar kind of crazy propulsion system. A possible alien artifact would be absolutely worth the risk of launching a nuclear upper stage. Workable designs for NERVA are on the books. I'm sure we could think of some way to fire a very small probe at this thing by putting an absurd amount of rocket muscle behind it. Even a fast flyby with a few measurements and shots would be worth it.

I guess barring that we will soon have the JWST.

This. We have the technology to go this fast... but no pressing need. Should a pressing need arise I do not doubt we will begin immediately. SpaceX could be turning around Falcon Heavy after Falcon Heavy as we loft fuel tanks to a “probe” we assembled in orbit out of an existing space worthy hardware “core” capable of autonomous operation such as a Soyuz or Dragon capsule, any instrumentation could be just built as stand alone modules and bolted to a separate set of communication hardware. We could conceivably build a probe and chase this thing down to contact in under 5 years.

If it took 6 months to build (!!), could we go fast enough to catch up to it in a reasonable time?

Just thinking about this scenario is enough to give me goosebumps.

Imagine the alien probe about to leave the outer perimeter of our solar system while our makeshift-to-the-aliens probe is trying to catch up to it while detonating one nuke after another.

You'd think that would catch their attention.

"See look at that propulsion system! I told you they were f'ing crazy. Fire the engines again for another burn, quick. Let's get some distance before they figure out that you can create a quantum singularity and the whole solar system goes up." - the aliens

NERVA? nah. I'd probably go as far as getting the dust of the Project Orion and Medusa spacecraft. That's how you get there fast.

Well that depends on whether it slows down to have a listen before moving on, now doesn't it?? :)