Citingmedia reports, a number of witnesses in northwest Australia on the evening of June 14 saw a green fireball across the sky, quickly became a hot topic on social media. Reported that in Australia’s South Australia and Victoria can also observe this phenomenon.
Astronomers believe the “green fireball” is likely to be an asteroid. Experts say this could be an asteroid numbered 2002NN4, because it is expected to pass through Earth at this time. The researchers believe that despite the clear green light, the planet is about 5.2 million kilometers away from us, about 13 times the distance between Earth and the moon.
So how did astronomers determine that it was an asteroid, not a spacecraft, a defunct satellite, or other orbital junk? In fact, the object can be seen in video taken by witnesses as complete, which is a very important indicator. Because usually man-made objects break up after they enter the atmosphere, only meteors or something like that remain in shape.