An asteroid large enough to destroy a city has passed between the orbits of the Earth and the Moon – luckily for us, missing both. The object, named 2023 DZ2, was discovered a month ago. As predicted by scientists, it passed within 175,000km of the Earth on Saturday after flying past the Moon.
It is rare for such a huge asteroid – estimated to be between 40 and 90m in diameter – to come so close to the planet.
Astronomers described it as a once-in-a decade event. According to Nasa, it was an important opportunity for astronomers to increase their knowledge of asteroids, in the event that a dangerous object were discovered with the potential to hit Earth.
“There is no chance of this ‘city killer’ striking Earth, but its close approach offers a great opportunity for observations,” said the European Space Agency’s planetary defence chief, Richard Moissl.
Mr Moissl said preliminary data suggested 2023 DZ2 was “a scientifically interesting object”.
But he added that more data was needed to determine the asteroid’s composition.
With such a close pass of the Earth, the asteroid was visible through binoculars and small telescopes across the globe.
A live web broadcast of its approach was provided by The Virtual Telescope Project.
The object looks set to return towards Earth’s orbit in 2026, but scientists have ruled it out as a threat to the planet on that occasion, too.
Earlier this month, a similarly sized asteroid, 2023 DW, was briefly given a one-in-432 chance of hitting Earth on Valentine’s Day 2046.
Moissl said 2023 DW was now expected to miss Earth by some 4.3 million km.
Even if such an asteroid was determined to be heading our way, Earth is no longer defenceless.
Last year, NASA’s Dart (Double Asteroid Redirection Test) spacecraft deliberately slammed into the pyramid-sized asteroid Dimorphos.
Before Dart’s impact, it took Dimorphos 11 hours and 55 minutes to orbit its larger parent asteroid, Didymos.
See Live Virtual Telescope video