by surprise

Vance's first major foreign speech, at the Munich Security Conference in mid-February, caught many by surprise.

For example, on average in any given year, an object the size of 2024 YR4 has perhaps a one-in-a-thousand chance of striking the Earth or taking us by surprise.

That's the level at which it would become a one on the Torino Scale: If we discover an object and it has a probability higher than just sort of the average background of being taken by surprise in any given year.

We simply need to do a thorough job of cataloging them as the first step towards making sure that we are never taken by surprise, by any sizable object.

Last August, Ukraine made a lightning thrust into the Russian Kursk region, taking border guards by surprise.