NASA has shown radar images showing a stadium-sized asteroid flying past the Earth, Space reports.
Asteroid 2008 OS7 flew past the Earth on February 2 at a distance of 2.9 million km, which is about 7.5 times further than the distance between the Earth and the Moon.
Although there was no risk that the asteroid would harm the planet, scientists at NASA’s Jet Propulsion Laboratory (JPL) used the Goldstone Solar System Radar (GSSR) to obtain a series of images of the asteroid as it flew past Earth.
The new observations helped scientists determine its exact size.
The asteroid was first discovered in 2008 during a search for near-Earth objects. At the time, scientists estimated it to be an asteroid 200 to 500 meters wide.
Using JPL radar observations, scientists have found that the asteroid is much smaller than initially estimated. Now they believe that it is about 150-200 meters wide.
Observations also showed that 2008 OS7 rotates at an unusually slow speed, making one full rotation every 29.5 hours.
According to JPL, the Goldstone Solar System Radar’s DSS-14 antenna is the world’s only fully steerable planetary radar system. It can be used to observe space debris, solar system objects, and near-Earth asteroids such as 2008 OS7.
