> With the typical albedo of 5% for an asteroid, the diameter of 3I/ATLAS needs to be 20 kilometers in order to account for its brightness. But as argued in my

> With the typical albedo of 5% for an asteroid, the diameter of 3I/ATLAS needs to be 20 kilometers in order to account for its brightness. But as argued in my first paper about it, the reservoir of rocky material in interstellar space can only deliver a 20-kilometer rock once per 10,000 years. He's still repeating this? Loeb previously performed an analysis that said if 3I/ATLAS wasn't a comet and was instead an asteroid with no coma, it would have to be an unusually large object to explain its brightness. Since then, we pointed the Hubble at it and clearly saw that it was a comet, not an asteroid, so the entire premise of the calculation is wrong. > When I proposed that it might be technological in origin, just like 2020 SO, this notion was ridiculed by comet experts, in a historical echo of Chladni’s scrutiny. To quote Carl Sagan: "They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown."