Sunday, January 24, 2021
It might not be a sail, but it's salient
As mentioned before, I'm inclined to respect Abraham Loeb's thinking because he has publicly opposed some (not all) of the usual "scientific" orthodoxies.
I wasn't especially impressed by his insistence that the long object called Oumuamua is alien tech.
After reading the details more carefully, I'm still not impressed by his set of statistical assumptions... BUT ... there's one basic fact about the object that IS distinctive and unusual. At least in what I've read, Loeb doesn't seem to consider this fact salient. (He may be hitting the point elsewhere.)
The salient fact is the rotation itself. The object rotates steadily every eight hours or so. Loeb uses the observed patterns from this rotation to draw conclusions which aren't nearly as convincing as the STEADY rotation.
Try rotating a metallic object in a permanent magnetic field. (EG the shaft of a stepping motor in a printer.) Hysteresis will fight hard to slow it down. You're sending energy into the field, which can be used to generate current if the device is set up properly.
If this thing is even partly metallic, it simply can't keep rotating in the sun's magnetosphere. It would have slowed to a stop long ago. Giant objects like planets have enough inertia to keep going, but even the earth is gradually slowing down from hysteresis. This skyscraper-sized object doesn't have nearly enough inertia to keep turning.
¶ 7:23 AM 
