November 16, 2013
NASA To Launch Lighting-Studying Firefly Satellite Later This Month
[ Watch the Video: Firefly Mission to Study Lightning ]
NASA is preparing to launch an inexpensive, football-sized probe to study lightning, including its effects on the atmosphere and the possible link between the phenomenon and powerful energy bursts known as terrestrial gamma ray flashes (TGFs), the US space agency announced on Friday.
The probe has been dubbed Firefly, and it is currently scheduled for a launch later this month. The mission is sponsored by the National Science Foundation (NSF) and is part of the organization’s CubeSat program, which allows NASA officials to launch smaller satellites that are less expensive but still capable of performing quality space-related scientific research.
“We can do great science with these small missions,” explained Doug Rowland, the principal investigator for Firefly at NASA's Goddard Space Flight Center in Maryland. “Firefly will gather up to a year of observations on the mysterious workings of lightning.”
“Lightning is so familiar we tend to take it for granted, but we really don’t know the details of how it works – even though it is a critical part of the global electric circuit, and has obvious social and technological effects,” he added. That will be Firefly’s mission: to observe lighting and gamma rays from above, and to analyze the impact that these phenomenon have on the Earth’s surface and its atmosphere.
According to NASA scientists, the radiation that lighting generates is of such high intensity that it can generate antimatter and gamma rays within TGFs that are mere miles off the ground. TGFs were first discovered roughly two decades ago by researchers at the Compton Gamma Ray Observatory, the space agency explained.
“Gamma rays are thought to be emitted by electrons traveling at or near the speed of light when they're slowed down by interactions with atoms in the upper atmosphere," said Therese Moretto Jorgensen, program director in NSF's Division of Atmospheric and Geospace Sciences. “TGFs are among our atmosphere's most interesting phenomena.”
Since the electrons required to produce gamma rays are so fast-moving and energetic, scientists were unable to explain what process near our planet would be able to boost them up to such high speeds, NASA explained. In fact, prior to the discovery of TGFs, scientists believed that electrons moving this quickly could only be generated near larger objects such as black holes, stars or galaxies.
“Lightning by itself is thought to be only a tenth as strong as would be needed to accelerate the electron beams to such incredible speeds, but scientists have hypothesized that perhaps some lightning is triggered by an electron avalanche, a runaway chain reaction that pushes electrons up to these incredible speeds,” the space agency said. “Understanding the mechanism for what accelerates the electron beams near Earth will help scientists understand how the same process happens throughout the rest of the universe.”
“The idea that some of the lightning overhead may be triggered by the same processes that happen in supernovas and cosmic particle accelerators is mind-blowing,” Rowland added. “I’ve never looked at thunderstorms the same way since learning about these ideas.”
Firefly’s launch window opens on November 19, and it will be launched into space along with 27 other CubeSat satellites and NASA’s Total solar irradiance Calibration Transfer Experiment (TCTE), a probe which will record the sun’s total energy output from space. The CubeSat instruments are typically produced on a smaller budget than larger satellites, with the price tags for these devices starting at $100 million, the agency said.