I was recently contacted by an editor at the venerable magazine Condé Nast Traveler to write a guide to what’s in the sky for world travelers in 2025. They published it over the weekend, so please take a look. Many of the events are visible from the US, so go see what there is to see!

As you may have heard, the chances of an impact in 2032 from the recently discovered asteroid 2024 YR4 have gone up a bit to 2.2%. Those are still long odds, as I wrote in a Scientific American article, the odds of an impact generally go up a bit before they drop to 0:

Irritatingly, the statistical chance of impact sometimes increases first—which is what happened with 2024 YR4 in recent days. Remember, the asteroid is somewhere near the vertex of a large cone, and we don’t know where. If Earth is near the centerline of that cone, then as the cone narrows with better observations, we’re still inside it. The chance of impact goes up. But then, almost always, the cone narrows further and winds up pointing in a slightly different direction, leaving Earth safe outside it, and we can all breathe a sigh of relief.

The real problem is that we just don’t know its orbit well enough to accurately predict whether it will hit or not in December 2032. We need more observations of it, but it’s currently heading away from Earth so it’s getting fainter, and won’t be back in our neck of the solar system until 2028.

However, it’s not too faint yet to observe with JWST! A team of astronomers put together a proposal to take a look at YR4, and were awarded Discretionary Director’s Time to do so — DDTs are used to get timely or important observations more rapidly than the usual year-long wait to get observations.

It’s hard to say how much the observations will increase the accuracy of the asteroid’s orbit calculations; because it’s currently headed away from us it’s not moving much on the sky, so its exact direction is more difficult to know (like standing on one lane of a two-lane road and seeing a car coming toward you; until its much closer it’s hard to know if it’s in your lane or the one next you).

That’s not the main purpose of the JWST observations, though: they’re going to help astronomers nail down the size of the asteroid.

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