Just because asteroid collisions are unlikely, it does not mean they are impossible.
On Wednesday, scientists across the world were surprised by the unexpected entry of a previously undetected asteroid into Earth’s atmosphere. The small asteroid, designated 2024 RW1 and measuring just one meter (3ft) in width, was only identified a mere eight hours before it blazed across the sky above the Philippines. Fortunately, the asteroid was too tiny to pose any damage. However, this unexpected event serves as a stark reminder of the potential hazards lurking in our solar system, highlighting the need for monitoring and efforts to better prepare for future asteroid encounters.
Experts warn that several asteroids are at risk of smashing into Earth, Live Science reported.
1. Bennu
Meet Bennu.
Bennu is a near-Earth asteroid that is being explored by NASA’s OSIRIS-REx mission. OSIRIS-REx arrived on Bennu in Dec. 2018 and expected to find a surface similar to a sandy beach. Expectations did not match reality.
Full episode: https://t.co/xH4Gz1RZJbpic.twitter.com/uUtLA2I6kf
— NASA Artemis (@NASAArtemis) March 2, 2020
Asteroid Bennu, discovered in 1999, currently poses the greatest risk of impacting our planet. Measuring 1,574ft in diameter and weighing 67 million tonnes, it’s wider than the Empire State Building and 200 times heavier. NASA observations indicate a 1 in 2,700 chance of impact on September 24, 2182. If Bennu collides with Earth, it would release energy equivalent to 1.4 billion tonnes of TNT, surpassing the combined energy of all nuclear weapons ever detonated.
2. 2023 DW – The Valentine’s Day asteroid
Asteroid 2023 DW is predicted to have a significant chance of colliding with Earth on February 14, 2046. With a diameter of 166ft (50m), it’s comparable in size to the asteroid that caused the destructive Chelyabinsk event in 2013. Travelling at 21.78 km/s relative to the sun, a potential impact could level an entire city. Initially, space agencies estimated a concerning 1 in 607 chance of collision. However, recent observations have significantly reduced the risk.
3. 1950 DA
Asteroid 1950 DA, measures a massive 4,265ft (1.3km) in diameter and weighs 71 million tonnes. Its massive size and potential impact make it the most significant threat to Earth, with a collision releasing energy equivalent to detonating 75 billion tons of TNT, capable of triggering a global catastrophe on the scale of the dinosaur extinction event. Currently, the asteroid has a 1 in 34,500 chance of impacting Earth on March 16, 2880. In 2032, it will safely pass within 6,959,357 miles (112,000,000 km). In preparation for potential future threats, NASA and ESA are already testing asteroid deflection methods, including high-speed satellite collisions, to push dangerous asteroids off course.
4. 2023 TL4
Asteroid 2023 TL4, discovered last year, has been identified as a potentially civilisation-ending threat due to its massive size and weight. Measuring 1,083ft (0.33km) in diameter and weighing 43 million tonnes, this space rock could unleash a blast 150 times more powerful than the Tsar Bomba. Fortunately, scientists have estimated a relatively low collision risk of 1 in 181,000 on October 10, 2119, providing ample time for space agencies to take action.
5. 2007 FT3
Asteroid 2007 FT3 is classified as a “lost asteroid” since it was last observed in 2007. Despite the uncertainty, NASA estimates a low probability of impact, with a 1 in 10 million chance (0.0000096%) of striking Earth on March 3, 2030, and a slightly lower chance of 1 in 11.5 million (0.0000087%) on October 5, 2024. If an impact were to occur in either year, the asteroid’s energy release would be equivalent to 2.6 billion tons of TNT, potentially causing regional devastation, but unlikely to trigger a global catastrophe.
6. 1979 XB
Asteroid 1979 XB, unseen for approximately 40 years, is another “lost asteroid”. Despite the uncertainty, scientists have estimated a 1 in 1.8 million chance (0.000055%) of impact on December 14, 2113, based on observations from its initial discovery on December 11, 1979. If 1979 XB were to collide with Earth, the impact would release an enormous amount of energy, equivalent to the detonation of 30 billion tons of TNT.
Asteroids colliding with Earth
Asteroid collisions with Earth are surprisingly common, with NASA estimating 48.5 tonnes of meteoric material entering our atmosphere daily. Most burn up, producing shooting stars. However, larger objects that pierce the atmosphere and impact Earth are rare. Just because asteroid collisions are unlikely, it does not mean they are impossible.
To mitigate this risk, NASA and the European Space Agency operate programs to identify, categorise, and track Near Earth Objects (NEOs). These initiatives help monitor potential threats, ensuring we’re better prepared for an asteroid impact.
