On February 15, 2013, a semitrailer-size meteor exploded over Chelyabinsk, Russia, causing widespread damage and injuries. Despite being the most significant space object in a century, it arrived undetected from the Sun's direction. Such events are rare, with estimates suggesting similar occurrences every 50 to 100 years.
Larger asteroids pose even less frequent threats. Although over 33,000 near-Earth objects have mapped orbits, the Chelyabinsk incident highlights the need for improved detection methods to identify potential hazards concealed in the solar blind spot.
Astronomers' Ongoing Battle Against Hidden Cosmic Threats
Astronomers emphasize the challenge of assessing the risk posed by unseen asteroids, particularly those of considerable size capable of causing widespread destruction and potential mass extinction events. The unpredictable trajectories of these celestial bodies around the Sun raise concerns among experts, compelling astronomers to intensify efforts in locating hidden asteroids in the Solar System.
Amy Mainzer, a planetary science professor, stresses the critical importance of identifying these objects, as knowledge enables better risk estimation and facilitates monitoring, deflection, or population warnings if necessary.
The Sun's brilliance constantly conceals numerous asteroids, including Apollo asteroids and the Atens, the latter being particularly perilous due to their proximity to Earth's orbit, often crossing it when barely visible in the night sky. Scott Sheppard, a scientist at the Carnegie Institution for Science, highlights the potential danger posed by Atens, as their orbits make them challenging to detect.
While many asteroids are expected to burn up in Earth's atmosphere upon entry, there is a significant concern about larger, city-killing asteroids measuring over 460 feet in diameter. Amy Mainzer reveals that approximately 40% of these sizable asteroids have been identified, leaving an estimated 14,000 yet to be discovered.
5 Most Dangerous Asteroids in the Solar System
In the Sun's glare, the possibility of far larger "planet killer" asteroids, exceeding 3,280 feet in diameter, adds to the complexity of the challenge.
NASA's Center for Near Earth Object Studies (CNEOS) employs the Sentry impact-monitoring system to analyze potential future orbits of hazardous asteroids, highlighting five known risks while acknowledging the existence of potentially unknown threats concealed in the sun's glare.
Bennnu
The near-Earth asteroid Bennu, with a size of 0.30 miles (0.49 kilometers) and a mass of 74 million tons (67 million metric tons), discovered in September 1999, currently presents the highest risk of impacting Earth, with a calculated 0.037% chance during its close approach on Sept. 24, 2182. Its potential impact is capable of causing regional destruction and millions of casualties if it were to strike a densely populated area.
29075 (1950 DA)
Measuring 0.81 miles (1.3 kilometers) in size and with a mass of 78 million tons (71 metric tons), this asteroid is identified as the second-riskiest object, having a 0.0029% chance of impacting Earth on March 16, 2880, and posing the potential for a global catastrophe with an energy release equivalent to 75 billion tons of TNT if a collision were to occur.
2023 TL4
With a size of 0.20 mile (0.33 kilometer) and a mass of 47 million tons (43 million metric tons), it immediately emerges as one of the most potentially hazardous asteroids, exhibiting a 0.00055% chance of striking Earth on Oct. 10, 2119, and if such an impact were to occur, it would release the energy equivalent to the detonation of 7.5 billion tons of TNT.
2007 FT3
The "lost asteroid" 2007 FT3, measuring 0.21 miles (0.34 kilometers) in size and weighing 54 million tons (49 million metric tons), unseen since 2007. It has a 0.0000096% chance of striking Earth on March 3, 2030, and a slightly lower probability of 0.0000087% on Oct. 5, 2024.
If an impact were to occur in either year, it would release the energy equivalent to the detonation of 2.6 billion tons of TNT, causing significant regional damage but not triggering a global catastrophe.
1979 XB
The "lost asteroid" 1979 XB, measuring 0.41 miles (0.66 kilometers) and weighing 390 million tons (354 metric tons), has been unseen for approximately 40 years and with a poorly understood orbit since its observation on Dec. 11, 1979. It has a 0.000055% chance of impacting Earth on Dec. 14, 2113, with the potential collision releasing energy equivalent to the detonation of 30 billion tons of TNT.
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