Co-author here. We obtained spectroscopic measurements of 'Oumuamua, and its surface closely matches D-type asteroids and comet nuclei, which are dark, reddish and organic-rich.

The spectroscopy seems pretty normal, but the shape is kinda freaking me out. If there were a single other object we'd ever seen which looks like this, that'd be different. But this seems really unique.

Is there a point where you, as a sober professional, start to entertain outlandish theories about something like this? Has this crossed that threshold?

Of course an asteroid, hollowed out somewhat, makes for a good spaceship. Especially if you're trying to be covert.

Perhaps someone has discovered warp drives (is gravitational wave detection the first step) and the Federation have sent a ship to observe us.

If you wanted to disguise a probe, it seems the ideal form would be a black body, not to disguise it as an asteroid, I would guess. Unless they're playing mind games.

Anyways, given all the EM radiation we're tossing out into the void, some species' probe out there is going to pick up our existence sooner or later.

And at ~395 earth-moon distances it's difficult to imagine how effective a 400-meter object, disguised as an asteroid, would be at seeing much detail on earth.

But it is tantalizing and fun to imagine--the appearance of a gravity boost... Flat surfaces... Near to earth... Lack of any ice or outgasing, a solid object, many characteristics not seen in other known-asteroids, rotating on its long axis... :)

> And at ~395 earth-moon distances it's difficult to imagine how effective a 400-meter object, disguised as an asteroid, would be at seeing much detail on earth.

Ah, but it's a carrier for the small, stealthy probes!

And waterbears.

Gravitational wave detection is nowhere near the first step to any sort of warp drive. In fact it is looking the like the nail in the warp drive coffin. I, and no doubt many others here, was hoping the new detectors would be picking up all sorts of tiny wave sources buzzing around us, a civilization of warp drives just beyond our previous limits of observation. But no, no tiny warp signatures. We are still alone. If ET is in our local galaxy he isn't using warp drives, only reducing their possibility.

Too bad we don't have a radar image! It would have been awesome to see the shape of this in Arecibo hi resolution dopler/delay.

" its surface closely matches D-type asteroids and comet nuclei"

That's what they want you to think!

Thanks!

>organic-rich.

So you're saying it's a bio-ship! ldenneau confirms it's aliens!

> I'll say it: did anyone consider an alien spaceship?

See some interesting back-and-forth on this here: https://www.reddit.com/r/space/comments/7ealls/solar_systems...

I doubt that any scientist working in academia would make such a claim. Career suicide, unless you're right and it's confirmed. Scientists tend to be a lot more cautious in their statements, unless they're looking for funding...

Well, if so - they didn't find anything of interest as they are now leaving...

https://www.popsci.com/interstellar-object-solar-system#page...