Astronomers Discover Fast-Moving Asteroid Hidden in Sunlight, Revealing a Critical Weakness in Planetary Defense
WASHINGTON D.C. – Astronomers have identified a new asteroid, designated 2025 SC79, lurking within the glare of the Sun, a finding that underscores a significant challenge in tracking perhaps hazardous space rocks. the asteroid, confirmed by observations from the Gemini and Magellan telescopes following its initial sighting in September by the Blanco 4-meter Telescope’s Dark Energy Camera, is especially noteworthy for its rapid orbit and size.
The newly discovered asteroid completes an orbit around the Sun in just 128 days,making it the second-fastest asteroid ever identified. it measures approximately 2,300 feet (700 meters) in diameter – nearly twice the height of the Empire State Building – classifying it as a “planet killer” asteroid, a type astronomer Scott Sheppard of Carnegie Science has been actively searching for.
The difficulty in detecting 2025 SC79 stems from its location. “The most risky asteroids are the most challenging to detect,” Sheppard explained in a Carnegie Science release. Unlike most asteroids visible in the dark night sky, this one resides in a region where it’s only observable during twilight, obscured by the Sun’s brightness.
This “twilight” zone presents a unique obstacle to planetary defense efforts. “Asteroids lurking near the Sun…are only visible at twilight,” Sheppard stated.While astronomers routinely track many asteroids to assess potential Earth impact risks, these sun-grazing objects pose a ”serious impact hazard” if their orbits bring them close to our planet.
The discovery highlights the need for improved detection strategies. Many asteroids reside within the asteroid belts, but gravitational disturbances can alter their paths, sending them into orbits that are harder to observe. Sheppard emphasizes that understanding how these asteroids arrive in these challenging locations is crucial, stating, “Understanding how they arrived at these locations can help us protect our planet and also help us learn more about Solar System history.”
Further study of 2025 SC79’s composition may yield valuable insights into identifying similar, potentially dangerous asteroids hidden in the Sun’s glare.
