In 2025, Earth will experience several close encounters with asteroids, providing a rare and exciting opportunity to study these fascinating space rocks. While most of these asteroids will safely pass by without posing any threat to our planet, these flybys offer a chance for astronomers and skywatchers to observe them as they make their closest approaches to Earth. Here’s a guide to some of the most notable asteroid flybys and close approaches to look out for in 2025.
What is an Asteroid Flyby?
An asteroid flyby refers to an asteroid passing by Earth at a relatively close distance, allowing it to be observed and studied. These flybys occur frequently, but only a few are close enough to be detected by amateur astronomers and visible to the naked eye. The majority of flybys happen at distances far greater than the moon’s orbit, so there’s no danger of collision. However, these events are significant for scientists studying asteroid trajectories and preparing for potential future threats.
Notable Asteroid Flybys and Close Approaches in 2025
Here are some of the most exciting asteroid encounters in 2025:
1. 2000 SG344 – February 8, 2025
- Distance from Earth: 1.4 million kilometers (0.009 AU)
- Size: 120 meters in diameter
- About: One of the more well-known asteroids that regularly passes near Earth, 2000 SG344 will make a relatively close approach in February 2025. With a diameter of over 100 meters, this asteroid is large enough to be observed using amateur telescopes and offers a unique opportunity to study the surface of an asteroid of this size. It will pass at a safe distance but will be close enough to be an intriguing target for both astronomers and stargazers.
Key Observing Time: Best seen from the Northern Hemisphere in the evening.
2. 1998 QE2 – May 15, 2025
- Distance from Earth: 6.4 million kilometers (0.042 AU)
- Size: 2.7 kilometers in diameter
- About: One of the larger asteroids expected to approach Earth in 2025, 1998 QE2 will be well within observational range of both professional observatories and amateur astronomers. This asteroid is known for its unique characteristics, including its large size and distinct shape, which resembles a diamond or a spheroid. Despite its proximity, it poses no risk to Earth and will be a great target for asteroid study.
Key Observing Time: Visibility will peak in the early morning hours, making it best for observers with telescopes in the Northern Hemisphere.
3. 2004 BL86 – January 26, 2025
- Distance from Earth: 1.2 million kilometers (0.008 AU)
- Size: 325 meters in diameter
- About: One of the most anticipated asteroid flybys of 2025, 2004 BL86 will make a close pass to Earth in January. At 325 meters in diameter, this asteroid is large enough to be a significant target for astronomers. Its close approach offers a fantastic opportunity to learn more about the composition of near-Earth asteroids. It will be visible with moderate-sized telescopes, and astronomers are expected to gather valuable data on its orbit and structure.
Key Observing Time: Best observed in the early evening from the Northern Hemisphere.
4. 2010 WC9 – May 15, 2025
- Distance from Earth: 200,000 kilometers (0.0013 AU)
- Size: 30 meters in diameter
- About: 2010 WC9 is a small but fast-moving asteroid that will make an extraordinarily close pass to Earth in May. This asteroid is relatively small, but it will be very close, passing inside the Moon’s orbit, making it a rare opportunity to observe an asteroid passing so near. Due to its small size and rapid movement, it will require high-powered telescopes to track, but it will be an exciting target for astronomers and professionals alike.
Key Observing Time: The asteroid will be best observed with telescopes in both the Northern and Southern Hemispheres in the hours leading up to dawn.
5. 1999 AN10 – August 7, 2025
- Distance from Earth: 1.5 million kilometers (0.01 AU)
- Size: 800 meters in diameter
- About: 1999 AN10 is one of the largest asteroids expected to make a close approach in 2025. This asteroid has an orbit that brings it near Earth roughly once every 5-10 years. In 2025, it will pass at a safe distance but still close enough to be studied in detail. The size of this asteroid means it could be seen using large telescopes, and its proximity will allow astronomers to better understand its trajectory and potential for future encounters.
Key Observing Time: Best observed in the evening hours, with the asteroid visible in the Northern Hemisphere.
How to Observe Asteroid Flybys?
Asteroids are often visible with telescopes, and some of the larger ones can be seen with binoculars or even the naked eye if the conditions are right. Here are some tips for observing these space rocks:
- Use a Telescope: Larger asteroids, particularly those with diameters over 100 meters, are best viewed with a telescope. A 6-inch telescope or larger should be able to provide clear views of these objects.
- Check Sky Conditions: Clear, dark skies are crucial for observing asteroids, as they are often faint and can be hard to distinguish from background stars. Avoid light pollution by heading to a location away from city lights.
- Track Their Movements: Many asteroids move quickly across the sky. Use online tools like Heavens-Above or AstroViewer to track their movements in real-time.
- Observe with Friends: Asteroid flybys are more exciting when shared with others. Join an astronomy club or participate in public viewing events if available in your area.
Asteroid Impact Monitoring
While these flybys provide an exciting opportunity to observe asteroids up close, scientists continue to monitor the paths of asteroids for potential impact risks. Currently, no known asteroid poses an immediate threat to Earth, but missions like NASA’s Planetary Defense Coordination Office are actively studying ways to detect and mitigate any future risks from asteroids or comets.
Looking Ahead
2025 will offer multiple opportunities to witness these celestial wanderers as they pass close to Earth. Whether you’re an amateur astronomer with a small telescope or a professional researcher with access to more powerful equipment, these asteroid flybys will help expand our understanding of the solar system and the objects that travel through it.
Stay tuned for more updates as new asteroid encounters are discovered and tracked, and make sure to mark your calendars for these rare and fascinating events!