NASA Vigilantly Scans the Skies for Menacing Asteroids
In a constant effort to ensure the safety of our planet, NASA has been diligently scanning the skies for potentially dangerous asteroids. Recently, the space agency captured its first detailed views of asteroid 2008 OS7, a massive rock measuring between 200 to 500 meters in diameter. Although it passed by Earth at a distance of 1.8 million miles in early February, which is relatively close in cosmic terms, there was no risk of impact. NASA’s Jet Propulsion Laboratory in Southern California utilized a powerful radio antenna to gather information about the size, rotation, shape, and surface details of this near-Earth object (NEO).
The images of asteroid 2008 OS7 were taken using the Goldstone Solar System Radar, a massive radio telescope with a diameter of 230 feet. Radio telescopes work by beaming a signal towards the object of interest and capturing the reflected radio waves with an antenna. These detailed images provide valuable insights into the characteristics of asteroids and aid in understanding their potential threat to our planet.
While there are millions of asteroids in our solar system, our cosmic neighborhood is much less chaotic than it was during its formation approximately 4.5 billion years ago. During that time, objects were constantly colliding and merging, eventually forming planets and moons. “The solar system used to be a lot more violent than it is now,” says Sally Dodson-Robinson, a planetary scientist at the University of Delaware.
Fortunately, astronomers have made significant progress in identifying potentially hazardous asteroids. Over 90 percent of the half-mile-plus “planet-killer” asteroids that occasionally pass near Earth have been discovered, and there is no known threat of collision from these giant rocks for the next century. The likelihood of an impact in the next thousand years is also exceedingly low.
However, astronomers continue to discover thousands of nearby space rocks, with over 10,000 already identified. These asteroids, measuring over 460 feet in diameter, have the potential to cause significant regional destruction. Approximately 500 more of these objects are detected each year, but an estimated 15,000 still remain undiscovered.
It is important to note that while asteroids frequently pass through Earth’s neighborhood, significant impacts are rare. Every day, around 100 tons of dust and sand-sized particles fall through Earth’s atmosphere and burn up. On average, an “automobile-sized asteroid” plunges through our sky and explodes each year. Impacts by objects measuring around 460 feet in diameter occur every 10,000 to 20,000 years. Catastrophic events like the one that led to the extinction of the dinosaurs, caused by a rock half a mile or larger in diameter, happen on a 100-million-year timescale.
NASA’s continuous efforts to scan the skies for menacing asteroids play a crucial role in safeguarding our planet. By identifying and tracking these space rocks, scientists can assess the potential risks they pose and develop strategies to mitigate any potential threats. While the chances of a catastrophic impact are low, NASA’s vigilance ensures that we are well-prepared to protect our planet from any future dangers that may arise from the depths of space.