On the Origin of STEVE: Particle Precipitation or Ionospheric Skyglow?
Abstract
One of the recent developments in ionospheric research was the introduction of a subauroral spectacle called STEVE (Strong Thermal Emission Velocity Enhancement). Although STEVE has been documented by amateur night sky watchers for decades, it is an exciting new upper atmospheric phenomenon for the scientific community. Observed first by amateur auroral photographers, STEVE appeared as a narrow luminous structure across the night sky. Currently, only one scientific study has focused on STEVE, revealing that it corresponds to a narrow (tens of kilometers in north-south extent) and long (thousands of kilometers in east-west direction) structure located in the subauroral region. An important and fundamental question that arises from this study is the origin of STEVE; more specifically, does STEVE correspond to a new ionospheric phenomenon or is it due to particle precipitation? In this letter, we analyze a STEVE event on 28 March 2008 observed by Time History of Events and Macroscale Interactions during Substorms (THEMIS) ground-based All-Sky Imagers and a Polar Orbiting Environmental Satellite (POES). The POES-17 satellite crossed STEVE at the center of the All-Sky Imager field-of-view, allowing us to collect particle data simultaneously. These concurrent measurements show that STEVE might not be associated with particle precipitation (electrons or ions). Therefore, this event suggests that STEVE's skyglow (which we defined to be unrelated to aurora or airglow) could be generated in the ionosphere.
- Publication:
-
Geophysical Research Letters
- Pub Date:
- August 2018
- DOI:
- 10.1029/2018GL078509
- Bibcode:
- 2018GeoRL..45.7968G