CODEX Coronagraph: Unveiling a New Face of the Solar Corona
– First in the world to measure temperature variations in the solar corona at 3 to 8 solar radii
The Korea AeroSpace Administration (KASA, Administrator Yoon Youngbin) and the Korea Astronomy and Space Science Institute (KASI, President Park Jang hyun) announced on Wednesday, June 11, that they have successfully captured images showing temperature and velocity data of the Sun’s corona. These images were obtained using observational data from the CODEX (COronal Diagnostic EXperiment), a solar coronagraph jointly developed with NASA(National Aeronautics and Space Administration).
CODEX was launched aboard a SpaceX rocket from Kennedy Space Center in Florida, United States, on November 5 of last year. It was later installed on the International Space Station, where it underwent a series of test operations before commencing full-scale observations on February 17 of this year.
CODEX is an instrument that designed to observe the Sun’s faint outer atmosphere, known as the corona, by blocking the bright light from the solar photosphere using an occulting disk. While traditional coronagraphs could only measure the corona’s density, CODEX stands out for its use of narrowband filters that enable the measurement of both temperature and velocity in the faint corona — particularly in the region approximately 3 to 8 times the solar radii.
The distributions of temperature and velocity in the solar corona, along with their temporal variations, are expected to provide valuable insights into the inflow of matter and energy that constitute the solar wind. This, in turn, is anticipated to deepen our understanding of the corona and the solar wind, and to enhance predictive models of the Sun’s impact on Earth.
A key enabler of this achievement is the pixel-separated polarimetric camera platform technology applied to CODEX. This core technology allows for the precise separation and measurement of subtle polarization signals in high-resolution images, serving as the foundation for acquiring temperature and velocity data during this observation.
John Lee, Vice administrator of the Mission Directorates at KASA, emphasized, “This is a great example of the growing international cooperation in space exploration,” and added, “We will do our utmost to become a leading nation in solar research and space weather forecasting.”