AEPEX

AEPEX [CU Boulder]

AEPEX (Atmospheric Effects of Precipitation through Energetic X-rays) is a 6U-CubeSat scientific investigation mission that aims to better understand the influence of the magnetosphere on the Earth’s upper atmosphere through energetic particle precipitation (EPP).

One of the key uncertainties in reaching closure on how EPP impacts the atmosphere is the lack of knowledge regarding how much energy is put into the atmosphere via EPP. To address this uncertainty, the primary objective of AEPEX is to quantify the energy deposition to the atmosphere from energetic particles that precipitate from the radiation belts and other sources.

AEPEX aims to image precipitation of energetic electrons from the radiation belts - one of the main loss mechanisms for radiation belt electrons - through their X-ray signatures. As energetic electrons collide with the atmosphere, they produce X-rays, many of which are backscattered into space. By imaging these X-rays, the flux of electrons precipitating can be determined, along with their energy spectrum, spatial extent, and temporal variation. To measure hard X-rays, with energies above 50 keV AEPEX features an instrument called AXIS (Atmospheric X-ray Imaging Spectrometer), that uses compact and light off-the-shelf X-ray detectors designed for security X-ray systems with specially designed X-ray optics.

It was selected in 2021 by NASA's CubeSat Launch Initiative (CSLI) to be launched as part of the ELaNa program.