NASA’s probes keep their eyes in the space searching for any celestial objects, including asteroids and comets, coming closer to the earth’s orbit. The space agency is able to identify such objects months, and sometimes years before they come in the proximity of the earth. But this time, an approaching asteroid was only identified two days before it flew by the earth.
The major thing about the asteroid is that it flew by while being twice closer to the earth than the moon is. Named 2017 AG3, the near-earth object (NEO) passed through the earth’s orbit at a speed of 9.9 miles per hour on Monday. The data from Jet Propulsion Laboratory (JPL) of NASA revealed that the asteroid was closest to the earth at about 7:50 AM EST.
The asteroid was discovered just two days before the flyby on Saturday by the Catalina Sky Survey of the University of Arizona. The size of the space rock was measured to be between 50 and 111 feet (15 to 34 metres). The asteroid crosses the orbits of two planets – Venus and Earth.
In case the asteroid had entered the earth’s atmosphere, the outcome wouldn’t have been too extreme. The researchers at Purdue University explain if a porous rock asteroid of 111 feet enters the atmosphere at an angle of 45-degree, it would explode mid-air. However, the blast would be dozens of time stronger than the Hiroshima nuclear bomb explosion, releasing about 700 kilotons’ worth of energy.
Happening 10 miles above the earth, the impact on the ground would be negligible and it would have sounded nothing more than a heavy traffic. But, 2017 AG3 has the same size as the asteroid that struck Chelyabinsk, Russia in 2013, which caused shattered windows and some damage to buildings.
There are several space programs running that are made to specifically hunt down the near-earth objects. NASA’s NEOWISE recently spotted a couple of celestial objects approaching earth’s orbit. NEOCam is another infrared telescope that is designed to detect objects of 460 feet or larger.