Every night, the Gemini cloudcam atop Mauna Kea in Hawaii monitor storms approaching some of the world's largest telescopes. It often captures bright bolts of lightning lancing down to the ground below the towering dormant volcano.

On July 24th it captured something lancing up:

Gigantic jets over Hawaii
© Frankie Lucena
"This amazing lightning-like phenomenon is known as a Gigantic Jet," says Frankie Lucena of Puerto Rico, who processed the video. "They are related to sprites, but more powerful and easier to see with the naked eye."

Cloudcam video caught at least three of these jets springing from the tops of a powerful growing thunderstorm. The tallest of them reached all the way to the ionosphere some 80 km overhead.


"Gigantic Jets are much more rare than sprites," says Oscar van der Velde, a member of the Lightning Research Group at the Universitat Politècnica de Catalunya. "While sprites were discovered in 1989 and have since been photographed by the thousands, it was not until 2001-2002 that Gigantic Jets were first recorded from Puerto Rico and Taiwan." Only a few dozen Gigantic Jets have ever been seen, mostly over open ocean.

Sometimes called "space lightning," Gigantic Jets and their cousins the sprites are true space weather phenomena. They inhabit the upper atmosphere alongside auroras, meteors and noctilucent clouds. Some researchers believe they are linked to cosmic rays: subatomic particles from deep space striking the top of Earth's atmosphere produce secondary electrons that could, in turn, provide the spark for these upward bolts.

The link to cosmic rays is particularly interesting at this time. For the past two years, space weather balloons have observed a steady increase in deep space radiation penetrating our atmosphere. This increase is largely due to the decline in the solar cycle. Flagging solar wind pressure and weakening sunspot magnetic fields allow more cosmic rays into the inner solar system--a trend which is expected to continue for for years to come. These changes could add up to more Gigantic Jets in the future. Stay tuned!