The European Space Agency’s Solar Orbiter spacecraft — launched in February 2020 and taking the first-ever images of the sun at close range — has sent back one of the most detailed images of our star.
The widest high-resolution view of the sun so far was assembled from 200 images taken on March 9, 2025, while Solar Orbiter was about 48 million miles (77 million kilometers) from the sun. The sun is 93 million miles (148 million kilometers) from Earth.
It shows the sun’s hotter outer atmosphere, its corona (crown), the source of the solar wind — a stream of charged particles coming at Earth from the sun — and the space weather that causes geomagnetic storms and aurora. The image captures only ultraviolet — electromagnetic radiation with wavelengths shorter than visible light and invisible to the human eye.
What Is The Corona?
The sun’s corona is always in the sky, but it’s overwhelmed by the sun’s photosphere, which is a million times brighter. However, the corona’s temperature is around 1.8 million degrees Fahrenheit (1 million degrees Celsius), 150 times hotter than the photosphere.
Only during the brief “totality” phase of a total solar eclipse — which lasts only a few minutes and only from a narrow path across Earth’s surface — can the corona be glimpsed with the naked eye when it is seen as a halo of whitish light around the moon’s silhouette. The brevity of an eclipse makes it difficult for solar physicists to study the corona. However, live images of the sun are streamed back to Earth in real time by NASA’s Solar Dynamic Observatory.
How The Image Was Taken
Solar Orbiter has six ultraviolet telescopes taking the first observations from close to the sun. Its Extreme Ultraviolet Imager (EUI) camera captured six images at high resolution and two wide-angle views to create 200 individual images across a 5 x 5 grid. The images were then stitched together to create a giant mosaic. It can be downloaded in spectacular 12544 × 12544 pixels (157 megapixels) quality from the ESA website.
It comes the day after the Daniel K. Inouye Solar Telescope — the world’s largest solar telescope — on top of the Haleakala volcano in Hawaii produced a spectacular first image of sunspots on the sun.
Solar Maximum
The shape of the corona changes shape throughout the 11-year solar cycle, during which the sun’s magnetic activity waxes and wanes between “solar minimum” and “solar maximum. Solar Orbiter’s image comes as the sun is in its “solar maximum” period, which scientists at NOAA and NASA think began in October 2024.
Solar Orbiter’s image is essential because solar scientists need to understand what processes on the sun — and chiefly in its corona — cause geomagnetic disturbances on Earth so they can predict them, thus protecting critical infrastructure on Earth and in space.
When Is The Next Eclipse?
The next total solar eclipse is on Aug. 12, 2026. It will be seen from within a narrow path of totality that passes through eastern Greenland, western Iceland and northern Spain. Totality will last about two minutes. On Aug. 2, 2027, a totality lasting over six minutes will be seen from within a path passing through southern Spain, northern Morocco, Algeria, Tunisia, Libya, Egypt, Saudi Arabia and Yemen. The next total solar eclipse in the contiguous U.S. will occur on Aug. 22, 2044.
Wishing you clear skies and wide eyes.
