Researchers are tracking a gigantic storm on Saturn that is unleashing lightning bolts more than 1,000 times stronger than those found on Earth.

Using instruments aboard the international Cassini spacecraft, scientists from the University of Iowa first spotted the storm on Jan. 23.

But since the spacecraft was not in the right position to photograph the storm, scientists enlisted the help of amateur astronomers who confirmed a storm was raging in the ringed planet's southern hemisphere.

"It is clear that this is the strongest lightning activity that we've seen yet with Cassini since it has arrived at Saturn," Donald Gurnett of the University of Iowa said Tuesday.

Researchers recorded 35 consecutive episodes since the storm was first detected. Each episode lasted about 10 hours.

It's unclear how such lightning storms originate, but scientists think it might be related to the planet's warm interior.

Scientists hope to get a better view of the storm when the spacecraft executes a flyby near Saturn in the coming weeks.

Cassini, funded by NASA and the European and Italian space agencies, was launched in 1997 and took seven years to reach Saturn to explore the ringed planet and its many moons.

The mission is managed by NASA's Jet Propulsion Laboratory in Pasadena.