YR4 asteroid: The hits and near-misses you never hear about
If the asteroid was on course for a town or city, Dr Boslough compares the response to preparations made for a major hurricane, including evacuations and measures to protect infrastructure.
The Space Mission Planning Advisory Group will meet again in April to decide what to do about YR4.
By then most scientists expect the risk to have almost entirely gone, as their calculations of its trajectory become more precise.
We do have options beyond "taking a hit", as Dr Kumamoto puts it.
Nasa and the European Space Agency have developed technologies to nudge dangerous asteroids off course.
Nasa's Double Asteroid Redirection Test (DART) successfully slammed a spacecraft into the asteroid Dimorphos to change its path.
However scientists are sceptical if that would work in the case of YR4 due to uncertainty about what it is made of and the short window of time to successfully deflect it.
And what about the asteroids that do hit Earth? An awkward truth for scientists is that a direct strike on land far from humans is the ideal scenario for asteroids.
That gives them actual pieces from distant objects within of our solar system, as well as insights into Earth's impact history.
Nearly 50,000 asteroids have been found in Antarctica. The most famous, called ALH 84001, is believed to have originated on Mars and contains minerals with vital evidence about the planet's history, suggesting it was warm and had water on its surface billions of years ago.
In 2023 scientists detected an asteroid called 33 Polyhymnia which could have an element denser than anything found on Earth.
This superheavy element would be something entirely new to our planet. 33 Polyhymnia is at least 170 million kilometers away, but it's an indication of the incredible potential of asteroids for our understanding of science.
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Now that the chances are higher that YR4 will hit the Moon, some scientists are getting excited about that.
An impact could give real-world answers to questions they have only been able to simulate using computers.
"To have even one data point of a real example would be incredibly powerful," says Prof Gareth Collins from Imperial College London.
"How much material comes out when the asteroid hits? How fast does it go? How far does that travel?" he asks.
It would help them test the scenarios they have modelled about asteroid impacts on Earth, helping create better predictions.
YR4 has reminded us that we live on a planet vulnerable to collisions with something the solar system is full of – rocks.
Scientists warn against complacency, saying it is a matter of when, not if, a large asteroid will threaten human life on Earth, although most expect that to be in the coming centuries rather than decades.
In the meantime, our ability to monitor space keeps improving. Later this year the largest digital camera ever built will begin working at the Vera Rubin Observatory in Chile, able to capture the night sky in incredible detail.
And the closer and longer we look, the more asteroids spinning close to Earth we are likely to spot.
