Fireballs streak across U.S. and Japan skies, but what exactly are they?

Robin Burks, Tech Times 05 November 2014, 01:11 pm

Many excited U.S. inhabitants witnessed three fireballs streaking across the skies Monday evening. In Japan, others also saw a fireball whizzing through their night skies. But exactly what are these fireballs and why was one deemed a fake?

Astronomers use the word "fireball" for meteors that are larger than normal and shine brighter than the planet Venus in the night sky. The bright light happens when these objects travel at high speeds of at least 10 miles per second, and hit the Earth's atmosphere, which basically sets the meteor on fire.

However, one of the fireballs seen in the U.S. was a fake, the result of a marketing stunt by Red Bull, a company known for its wild and crazy antics. The company paid someone to jump out of a plane over Chicago. As he soared over the city, he released sparks behind him.

At first, the stunt puzzled NASA officials. Because the jumper was moving slower than a normal meteor, they assumed it was space junk, although there were no reports of anything entering Earth's atmosphere that night.

The other two U.S. fireballs, though, appear legitimate. The most visible one appeared over West Virginia, although many saw it from much farther away. But there's nothing to fear, according to Bill Cooke, head of NASA's Meteorite Environment Office at the Marshall Space Flight Center.

"People see fireballs all over the Earth, every night of the year," says Cooke. "This is not unusual for this time of the year."

People are also more likely to see fireballs this time of year thanks to daylight saving time. Skies grow darker sooner, so that increases the chance that people are outside seeing them.

The second fireball occurred over Arkansas. This one is probably a Taurid meteor, part of a system of meteors that appear nearly every year around this time. That meteor shower should last throughout this weekend.

The Japan fireball, which appeared in the southwestern portion of the country, was also confirmed as a meteor, but a specifically brighter one called a bolide. That fireball whizzed across Japanese skies Monday night, too.

"Observatories and other bodies received a number of reports of a fireball-like object in the skies over western Japan on Monday night, with experts saying it was likely a bolide— a very bright shooting star," writes The Japan Times.