[Cover art: artist's jokey painting of 'Oumuamua as an alien spaceship. From Shutterstock. Below is a more conventional guess about what Oumuamua looks like. From the European Southern Observatory.]

Painting - 'Oumuamua

Is an alien spacecraft nearby right now?

The chair of Harvard's astronomy department, Avi Loeb, thinks it may be.

And he's not backing down on his speculations, even as he's being ridiculed and scolded by other astronomers.

It's an alien standoff.

Here's the deal:

In 2017, a telescope saw a dot streaking through our solar system. A strange object, unlike anything we've ever seen before.

By studying the pixels, astronomers figured out that it was dark red, perhaps the size of a high school, long and thin and flat.

They called it 'Oumuamua — Hawaiian for "thing that reaches out first," or "scout."

There's no photographs of it. It passed 15 million miles from Earth; now it's out passed the orbit of Saturn. But because of the way it's flying, astronomers agree it doesn't come from our solar system. That's new. All the meteors, comets, dust and debris, everything we've ever seen — all from around here.

'Oumuamua is interstellar. From the stars. We've never seen that before.

Most interestingly, Loeb says it's not behaving like a rock tumbling blindly through space. "There is some force pushing it," Loeb told the New Yorker.

What's propelling it? Could be thrusters — Warp Drive, Speed, Chewy! Could be the calculations are wrong.

But Loeb theorizes that the craft could be a light sail.

Astronomers have talked about light sails for a while. You make a thin, light ship with a sail on it, like an old sailing vessel. Then you shoot lasers at the sail from your home planet, or you catch the rays from a nearby star — the solar wind.

Loeb wrote a paper this fall, published in a reputable journal, wondering aloud whether this object could be a ship pushed by light, possibly from our sun. That 'Oumuamua was sent to fly by the Earth for recognizance.

That the aliens, in other words, might be wanting to see what we're up to.

Is Loeb a nut who forgot to take is medication? Possibly. His interviews are full of tangents about Galileo and the Church, about what if Hitler had won the war, about the multiverse and string theory. He sounds a bit like a stoned freshman asking, "What if today's the day the fucking aliens came, man?!?"

And as his conjectures pinballed around the Internet by the algorithms in recent months, Loeb has started getting "petty personal attacks" from other scientists. They point out (rightly) that there's a lot of reasons to think 'Oumuamua is just another stone: cosmic driftwood, a loose rock, a clod of dirt.

But Loeb has a degree in plasma physics, was a member of the same research organization Einstein was, and has been at Harvard for 25 years. In interview after interview, he's not backing down from his "the aliens might be here" talk.

He insists (rightly): this is a weird object. And there's nothing unscientific about saying "maybe."