A massive asteroid longer than the London Bridge is set to pass by the Earth soon in a close flyby, on a cosmic scale, according to NASA's asteroid tracker.
Meet asteroid 388945 (2008 TZ3)
Designated 388945 (2008 TZ3), this large asteroid has an estimated size of 292.8 meters, as noted by NASA's Eyes on Asteroids webtool, which can be seen here. For context, the famous London Bridge in the United Kingdom's capital city spans a total length of 269 meters. It is possible that it could be larger, though, with the Center for Near-Earth Object Studies (CNEOS) at NASA's Jet Propulsion Laboratory (JPL) putting its size between 220 meters and 490 meters.
It's heading in the planet's direction at a speed of approximately 8.22 kilometers per second and will pass us by at a distance of over 5.7 million kilometers either late Sunday night or early Monday morning.
For context, the Moon orbits the Earth at a distance of roughly 384,000 kilometers, so this is much farther but is actually much closer on a cosmic scale.
Further, the size of the asteroid is enough to raise concern, as are all asteroids that exceed 140 meters in diameter.
How deadly can asteroids be?
Asteroid impacts are one of the worst possible natural disasters that could possibly occur due to their potential for sheer destruction.
According to research from the Davidson Institute of Science, the educational arm of Israel's Weizmann Institute of Science, an asteroid over 140 meters in diameter would release an amount of energy at least a thousand times greater than that released by the first atomic bomb if it impacted Earth.
Something even larger – over 300 meters wide like the asteroid Apophis – could destroy an entire continent. An asteroid over a kilometer in width – like asteroid 138971 (2001 CB21), which flew past the Earth in early March – could trigger a worldwide cataclysm.
There are many other asteroids of this size out of the over 1 million known asteroids in the solar system, and many of them do orbit the Earth. According to CNEOS, 388945 (2008 TZ3) has a rarity of 1, meaning an asteroid of this size or larger passes by the Earth once a month, meaning 12 times a year, on average. This is far more often than many other asteroids, where they can pass us by roughly every few days.
Regardless, asteroid 388945 (2008 TZ3) will almost certainly not be impacting the planet. In fact, NASA has declared the Earth free of risk of any catastrophic asteroid impacts for the next century. Other, smaller non-catastrophic asteroid impacts can still occur, however. In fact, one did so in mid-March when asteroid 2022 EB5 hit the planet.
But even so, scientists have continued to advance methods of asteroid detection and defense, including NASA's groundbreaking Double Asteroid Redirection Test (DART) mission that is set to test the possibility of asteroid deflection.