Project HEX will help scientists measure how air heated by aurora rises, by the distortion it creates in a man-made chemical trail dispensed by two sounding rockets. The rockets will reach an estimated 160 kilometers. HEX will be the first rocket ever to travel horizontally across the Aurora! As HEX travels sideways it releases trails of Tri-Methyl Aluminum (TMA), which will distort with vertical wind shear. The distortion of the TMA will be measured by observers in Toolik Lake, Arctic Village, and Old Crow. There will be two parts of the HEX mission, a horizontal and a vertical TMA release. The vertical TMA release will be between 80-180km and will allow measurement of horizontal wind shear in the active E-region. The horizontal and vertical releases together will allow scientists to develop better models of wind patterns in the E-region.

Click here for the full HEX powerpoint presentation (40mb) It may take a while to download, but is worth the wait.

HEX will Deliver its payload in the E-region of the ionosphere. This is where the majority of the Auroral activity will occur. The E-region is about 120 kilometers above the surface of the earth and got its name from early work involving radio communications.

In technical terms, the two sounding rocket flights will measure:

• Vertical and horizontal zonal neutral winds near a stable auroral arc system lying ~300 km north of Poker Flat, using ground-based images to triangulate and hence deduce the drift of an approximately 200-km long, near-horizontal tri-methyl aluminum (TMA) trail deployed at ~160-km altitude (H-rocket);
• Height-resolved horizontal wind vectors between 80- and180-km altitude using two near-vertical TMA trails (V-rocket);
• A two-dimensional (latitude, altitude) cross section of the auroral arcs' l557.7-nm or l391.4-nm luminosity distribution using tomographic inversion of a payload photometer's scans in the plane of the trajectory (H-rocket); and
• Relative plasma density variations along the horizontal trajectory using a payload plasma probe (H-rocket).
  

The horizontal and vertical HEX missions have different propulsion systems because of the different natures of their missions. The horizontal HEX will be attached to a Black Brant X, and contain a Nihka rocket motor to power its horizontal flight. The vertical HEX will be mounted on an Improved Terrier Orion rocket motor.

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