NASA's CODEX Telescope Captures Unprecedented Solar Atmosphere Images

NASA's Coronal Diagnostic Experiment (CODEX) telescope, recently installed on the International Space Station (ISS), has successfully captured its first images of the sun's outer atmosphere, unveiling subtle fluctuations that have never before been documented. This development, announced during the 246th meeting of the American Astronomical Society on June 10, 2025, marks a significant advancement in solar research, potentially aiding scientists in predicting hazardous space weather events.

The CODEX telescope, which arrived at the ISS on November 5, 2024, aboard a SpaceX Dragon cargo capsule, is a coronagraph. This specialized instrument blocks out the solar disk, enabling it to focus on the sun's corona with unprecedented clarity. The design includes an occulting disk approximately the size of a tennis ball, held by three metal arms, which casts distinctive shadows in the resulting images. According to Jeffrey Newmark, a heliophysicist at NASA's Goddard Space Flight Center and principal investigator for CODEX, these observations mark a new frontier in solar studies. "These are brand new observations that have never been seen before, and we think there's a lot of really interesting science to be done with it," he stated.

The primary focus of CODEX is to analyze how the solar wind—composed of superheated particles ejected from the sun—interacts with the corona. Previous coronagraph experiments primarily measured the material density in the corona, whereas CODEX aims to measure the temperature and speed of the solar wind. Newmark elaborated on this, explaining that the telescope utilizes four narrow-band filters to assess temperature and speed. "By comparing the brightness of the images in each of these filters, we can tell the temperature and speed of the coronal solar wind," he noted.

Recent observations have indicated that the sun's outer atmosphere can reach temperatures up to 1.8 million degrees Fahrenheit (1 million degrees Celsius), a staggering 175 times hotter than the sun's surface. Understanding these extreme temperatures is crucial due to their role in generating space weather phenomena that can affect satellite operations and communication systems on Earth.

The recent surge in geomagnetic storms, linked to coronal holes on the sun, underscores the importance of CODEX's findings. For instance, a significant storm on June 13, 2025, triggered auroras across 18 U.S. states, while another disturbance on June 25 briefly illuminated night skies. These events are part of the solar maximum phase of the sun's 11-year cycle, a period characterized by heightened solar activity.

Experts assert that CODEX's timing is optimal, as the sun's magnetic fields enter a phase of increased competition known as the "solar battle zone." This period of activity may lead to unpredictable solar behavior, making the insights provided by CODEX invaluable for future space weather predictions.

In conclusion, the CODEX telescope represents a groundbreaking achievement in solar research. By providing unprecedented insights into the sun's corona and its interactions with solar wind, it holds the potential to enhance our understanding of space weather and its implications for technology and life on Earth. As the mission progresses, researchers anticipate a wealth of new data that could reshape our understanding of solar dynamics and their far-reaching effects.

This significant advancement in solar observation reflects NASA's commitment to exploring and understanding the complexities of our solar system, aiming to safeguard technological infrastructure from the potential impacts of solar phenomena.