Topical Review

Regarding the detectability and measurement of coronal mass ejections

Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302, USA

^* Corresponding author: howard@boulder.swri.edu

Received: 30 December 2014
Accepted: 19 June 2015

Abstract

In this review I discuss the problems associated with the detection and measurement of coronal mass ejections (CMEs). CMEs are important phenomena both scientifically, as they play a crucial role in the evolution of the solar corona, and technologically, as their impact with the Earth leads to severe space weather activity in the form of magnetic storms. I focus on the observation of CMEs using visible white light imagers (coronagraphs and heliospheric imagers), as they may be regarded as the binding agents between different datasets and different models that are used to reconstruct them. Our ability to accurately measure CMEs observed by these imagers is hampered by many factors, from instrumental to geometrical to physical. Following a brief review of the history of CME observation and measurement, I explore the impediments to our ability to measure them and describe possible means for which we may be able to mitigate those impediments. I conclude with a discussion of the claim that we have reached the limit of the information that we can extract from the current generation of white light imagers, and discuss possible ways forward regarding future instrument capabilities.