What is HELEN?
HELEN is a network of four weather balloons carrying two payloads each. It's intended to be flown during thunderstorms to gather a radiation profile of the storm, which will help us learn about the mechanisms behind phenomena like Gamma Ray Glow and Terrestrial Gamma Ray Flashes.
Why are we developing HELEN?
Terrestrial Gamma ray Flashes have previously primarily been studied from satellites, which can't see weaker TGFs and have only about a 5km precision in pinpointing where they started. Observing a TGF from a balloon near the storm could help us learn how and why TGFs form, a question that is being researched by many atmospheric scientists, including some at NASA, NOAA, and UAH.
On March 3rd, 2018, HELEN completed it's first test flight with assembled detection instrument.
Assembled payload for initial test flight on March 3rd, 2018
EFM Measurements Printed Circuit Board
Assembled scintillator crystals, photomultiplier tube, and socket for radiation detection payload
Interior of assembled payload initial test flight on March 3rd, 2018