05-05-2025
In Photos: Giant Sunspot Appears On The Sun — How To Safely See It
A giant black spot has appeared on the sun's disk — and you'll need to go find an old pair of solar eclipse glasses to safely see it with your own eyes.
At over 87,000 miles (140,000 kilometers) wide, the sunspot — called AR 4079 by solar scientists who track the sun each day — is the largest of 2025 so far. Earth's diameter is 7,926 miles (12,756 kilometers).
The sun only occupies half a degree of the sky, so trying to find it while wearing solar eclipse glasses is not easy. Here's how to see the sunspot:
Note: it is dangerous to look at the sun through anything other than a pair of certified safe solar filters (solar eclipse glasses) bearing the ISO 12312-2 international safety standard. Don't make your own, don't use sunglasses and don't use welder's glass (sometimes the latter is safe, but only if it's Grade 13 or 14, which is hard to check). The American Astronomical Society keeps a list of Suppliers of Safe Solar Filters & Viewers.
A sunspot is a magnetic disturbance on the sun's surface. Appearing on the sun's visible surface — called the photosphere — they're cooler regions on the sun caused by a concentration of magnetic field lines, according to NASA. The "AR" in a sunspot's name stands for active region because sunspots are areas of intense and complex magnetic fields and the source of solar eruptions — solar flares and coronal mass ejections.
Solar flares are intense blasts of radiation that travel at light speed, while CMEs are vast clouds of charged particles that travel more slowly but are a major cause of geomagnetic storms on Earth. CMEs are frequently the root cause of displays of the northern and southern lights.
In the wake of last May 10-11's displays of aurora — the most intense since 2003, according to NASA — scientists announced the arrival of the solar maximum period. However, there is a good chance of an extended period of solar activity through 2025.
The number of sunspots wax and wane according to where the sun is in its solar cycle, which is, on average, 11 years long. The sun is currently at solar maximum, meaning the sunspots are bigger and more numerous than usual.
AR 4079 is about half the size of the sunspot seen during the "Carrington Event" in early September 1859. The landmark solar event saw astronomer Richard C. Carrington observe the most powerful solar flare ever recorded, which later created auroras down to the tropics.
The giant sunspot comes days after the world's largest solar telescope published its first spectacular image of the sun. A new instrument on the Daniel K. Inouye Solar Telescope in Haleakala, Hawaii, captures sunlight signals over a narrow range of frequencies, allowing it to map magnetic fields, solar flares and plasma at new levels of detail. Its new image revealed a cluster of sunspots covering 241 million square miles of the sun's surface.
Wishing you clear skies and wide eyes.
