Asteroid 2008 OS7, a stadium-sized space rock, recently made a safe pass by Earth, thanks to the vigilant monitoring of NASA’s radar system. On February 2, 2024, the asteroid came within a distance of 1.8 million miles (2.9 million kilometers) from our planet, approximately 7.5 times farther than the Earth-moon distance. While there was no cause for concern about the asteroid posing a threat to Earth, scientists at NASA’s Jet Propulsion Laboratory (JPL) utilized the advanced Goldstone Solar System Radar (GSSR) to capture a series of images as it passed by.
The radar observations provided valuable insights into the asteroid’s characteristics, particularly its size, which had previously been difficult to determine due to its distance from Earth. The GSSR, with its exceptional capabilities, allowed scientists to finally obtain clear images of the asteroid during this close encounter.
Asteroid 2008 OS7 follows an orbit around the sun every 2.6 years, coming closest to the sun within the orbit of Venus and venturing out past the orbit of Mars at its farthest point. Due to its size and proximity to Earth, it has been classified as “potentially hazardous.” However, there is no need for immediate concern as it will not come as close to our planet for another 200 years, according to JPL.
Initially discovered in 2008 during a routine search for near-Earth objects (NEOs), scientists estimated the width of asteroid 2008 OS7 to be between 650 and 1,640 feet (200 and 500 meters). However, the recent radar observations on February 2 revealed that the asteroid is actually smaller than previously thought, measuring around 500 to 650 feet (150 to 200 meters) across. Additionally, scientists discovered that it rotates at an unusually slow rate, completing one full rotation every 29.5 hours.
The Goldstone Solar System Radar’s DSS-14 antenna, located at the Goldstone Deep Space Communications Complex in California’s Mojave Desert, is the world’s only fully steerable planetary radar system. With its 230-foot (70 m) antenna dish, it can effectively observe space debris, solar system bodies, and near-Earth asteroids like 2008 OS7.
The recent radar observations of asteroid 2008 OS7 serve as a testament to NASA’s commitment to monitoring and studying potentially threatening asteroids. By utilizing advanced radar systems like the GSSR, scientists can gather crucial data about these celestial objects, helping to enhance our understanding of their characteristics and behaviors. This knowledge is vital in developing strategies to mitigate potential risks associated with near-Earth asteroids.
While the passing of asteroid 2008 OS7 was uneventful and posed no immediate danger, it serves as a reminder of the importance of continued vigilance and research in the field of planetary defense. NASA’s radar systems play a crucial role in safeguarding our planet and ensuring that we are well-prepared for any future encounters with asteroids that may pose a threat to Earth.