In case you missed them, here’s a few pieces I’ve recently written and published for Quanta magazine, Undark magazine, and Knowable magazine. Thanks as usual to all of my excellent editors. I’m only posting brief excerpts here, so if you’re interested, please check out the whole thing using the links below.

Interstellar Visitor Found to Be Unlike a Comet or an Asteroid

The mystery of ’Oumuamua, the first interstellar object ever observed, continues to deepen. A new analysis argues that if it were a comet, it would have broken apart as it passed near the sun.

Artist’s concept of interstellar object1I/2017 U1 (‘Oumuamua) as it passed through the solar system. (Image credit: ESO / M. Kornmesser)

Like a hit-and-run driver who races from the scene of a crash, the interstellar guest known as ’Oumuamua has bolted out of the solar system, leaving confusion in its wake. Early measurements seemed to indicate that it was an asteroid — a dry rock much like those found orbiting between Mars and Jupiter. Then by this past summer, astronomers largely came around to the conclusion that it was instead a comet — an icy body knocked out of the distant reaches of a far-off planetary system.

Now a new analysis has found inconsistencies in this conclusion, suggesting that ’Oumuamua may not be a comet after all. Whether it’s actually a comet or an asteroid, one thing is clear: ’Oumuamua is not quite like anything seen before.

The object was first spotted a year ago by scientists with the Pan-STARRS telescope in Hawaii. ’Oumuamua (a Hawaiian word meaning “scout”) appeared to be a rocky, elongated asteroid at first, a stubby cosmic cigar.

Other astronomers quickly joined in the hunt, measuring everything they could. (One team even trained radio telescopes on it to check whether it might be transmitting extraterrestrial broadcasts. It was not.)…

[Read the entire piece in Quanta magazine, published on 10 October.]

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