Vassilis Angelopoulos

Vassilis Angelopoulos’ primary area of scientific research is to understand how particles are accelerated in Earth's magnetosphere, how the upper atmosphere and ionosphere respond to space currents, and how the lunar environment is affected by its interaction with the solar wind. As Principal Investigator of NASA’s THEMIS and ARTEMIS missions he has led the development of the associated five satellites and twenty ground-based observatories, including the instrument hardware and the data analysis software, and is currently leading the scientific analysis phases of both missions. He played an active role in the mission requirements definition, systems engineering, mission design, and mission implementation through UCB, the mission verification program through JPL, and the ARTEMIS mission design through JPL. Using data from the THEMIS spacecraft, he has been studying the global evolution of Earth’s space environment in response to energy input from the solar wind, the sequence of events leading to the magnetospheric substorm instability, and the ionospheric effects of substorm currents. Using ARTEMIS data, he has been studying particle acceleration, reconnection and turbulence in the magnetotail and solar wind, as well as lunar crustal fields and particle reflection and evolution in the lunar exosphere. At UCLA since 2007, he has graduated eight Ph.D. students and is currently supervising six. He led the development and launch of the twin CubeSat ELFIN mission which is currently collecting high-quality particle data from low-Earth orbit, and is operated primarily by students in the Mission Operations Center on the UCLA campus. Major scientific discoveries include (1) identifying magnetic reconnection as the trigger of the avalanche of energy that powers sub-storms and storms; and (2) identifying the location of magnetic energy conversion in the magnetotail.