#Huge green fireball over Australia puzzles experts

Some residents of Australia received a pretty special treat earlier this week when a massive fireball appeared in the night sky. The event was captured by multiple onlookers, and as ABC News (that’s the Australian news agency, not the Disney-owned ABC) reports, the unexpected visitor streaking across the sky was especially unique, taking on a greenish hue as it endured an inferno while cruising through Earth’s atmosphere.

Perhaps even more interesting, there hasn’t been a good explanation for exactly what the object was. Now, before you go dreaming up an alien invasion scenario you should know that experts believe it was a natural phenomenon, but they haven’t offered many details beyond that very vague description.

So, how can experts be sure it was a natural object and not a spacecraft or even a chunk of a long-dead satellite or other orbiting junk? The fact that the object remained in one piece is a big indicator that it was some form of naturally-occurring space debris like a meteor or something similar. Manmade objects tend to break up as they are torched by the friction of the atmosphere, and this object maintained its form as it tumbled toward Earth.

“It’s absolutely stunning,” Renae Sayers of Curtin University told ABC. “It’s a ball of green … what you are seeling is a giant flash of light, it’s almost like a ball with this gorgeous long tail. What we tend to see, when objects like space debris, or if it’s a satellite burning up, what we tend to see is sort of like crackles and sparks. This is due to the fact that there is stuff burning up — so you’ve got solar panels going all over the place, you’ve got hunks of metal moving around as it’s burning up through our atmosphere.”

Many times, fireball sightings result in explosions. This happens when the object entering Earth’s atmosphere can’t handle the intense stresses of entry, and we get a big boom as a result. That didn’t happen this time around, and experts are still trying to explain exactly what everyone saw. One of the possible explanations, a “grazing fireball encounter,” would mean that the object never fully entered the atmosphere and kind of skipped off of our planet instead.

There were no initial reports of an impact, and nobody found any debris that has been made public. At the very least, if the object did strike the Earth it didn’t appear to do any damage, but it might have never made it to the surface at all.