An asteroid the size of a sports stadium fell near Earth this month without causing any damage, while NASA's powerful radar system looked on.
Asteroid 2008 OS7 passed by Earth on February 2, 2024, at a safe distance of 1.8 million miles (2.9 million km), about 7.5 times farther than the distance between Earth and the Moon. Although there is no risk of the space rock harming our planet, scientists at NASA's Jet Propulsion Laboratory (JPL) used the advanced Goldstone Solar System Radar (GSSR) to produce a series of images of the asteroid as it passed by us.
New observations helped determine the size of the asteroid, as it was too far away for most planetary radar systems to adequately image it until its closest approach this month.
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Asteroid 2008 OS7 orbits the Sun every 2.6 years, passing within the orbit of Venus at its closest point to the Sun and exiting past the orbit of Mars at its farthest point. 2008 OS7 is classified as “potentially dangerous” due to its size and how close it is to Earth, but it won't come that close to our planet for another 200 years, JPL wrote in a memo. statement About these new notes.
When it was first discovered in 2008 during a routine search for near-Earth objects (NEOs), scientists estimated asteroid 2008 OS7 to be about 650 to 1,640 feet (200 and 500 meters) across.
Using JPL radar observations on February 2, scientists found that the asteroid is much smaller than those initial estimates; They now believe it is about 500 to 650 feet (150 to 200 meters) wide. The new observations also confirmed that 2008's OS7 spins at an unusually slow rate, completing one full cycle every 29.5 hours.
The Goldstone Solar System Radar's DSS-14 antenna is the world's only fully steerable planetary radar system. According to the Jet Propulsion Laboratory (JPL).. It consists of a 230-foot (70 m) dish located at the Goldstone Deep Space Communications Complex in California's Mojave Desert and can be used to observe space debris, solar system objects, and near-Earth asteroids such as 2008 OS7.