Key Takeaways
- Astronomers discovered 2025 SC79, a skyscraper-sized asteroid orbiting the sun every 128 days
- It’s the second-fastest known asteroid and second object with orbit inside Venus
- The asteroid currently travels behind the sun, making it invisible for months
- Discovery helps identify potential Earth-impact threats in hard-to-spot regions
Astronomers have detected a massive, skyscraper-sized asteroid racing through our solar system at near record-breaking speed. Named 2025 SC79, this celestial body completes one orbit around the sun every 128 days, making it the second-fastest known asteroid in our solar system.
Discovery Details
Carnegie Science astronomer Scott S. Sheppard first observed the asteroid on September 27. According to Carnegie Science’s statement, 2025 SC79 represents only the second known object with an orbit inside Venus, crossing Mercury’s path during its 128-day solar journey.
“Many of the solar system’s asteroids inhabit one of two belts of space rocks, but perturbations can send objects careening into closer orbits where they can be more challenging to spot,” Sheppard explained. “Understanding how they arrived at these locations can help us protect our planet and also help us learn more about solar system history.”
Tracking Planetary Threats
Sheppard’s twilight asteroid search program specifically targets objects that could pose collision risks to Earth. The NASA-partially funded project uses the Dark Energy Camera on the National Science Foundation’s Blanco 4-meter telescope to detect “planet killer” asteroids hidden in the sun’s glare.
The NSF’s Gemini telescope and Carnegie Science’s Magellan telescopes confirmed the 2025 SC79 sighting. The asteroid is currently positioned behind the sun and won’t be visible to telescopes for several months.
Record-Holding Discoveries
Sheppard and his colleagues also discovered the fastest known asteroid in 2021, which takes 133 days to orbit the sun. The astronomer specializes in studying various solar system objects including moons, dwarf planets, and asteroids.
