Astrology

The sun turned spotless for the first time since February, Fox Weather reports

The sun showed no numbered active regions across its Earth-facing side on Friday, the first spotless day since Feb. 24, according to Fox Weather, which cited solar observations and images from NASA's Solar Dynamics Observatory; Yahoo News Canada confirmed the same spotless stretch, the first in nearly seven months.

Published

Weak flares still flickered at the edges#

Even with no visible sunspots, two zones close to the sun's southeastern and northeastern edges gave off faint B-class flares, though they counted as plage regions rather than numbered active ones, Fox Weather reports.

Solar activity stayed at very low levels into Saturday, with observers recording 10 B-class flares including a B9.9 flare that peaked at 1:35 UTC, and no new Earth-directed coronal mass ejections were seen during the period, according to Fox Weather.

Solar wind speeds held at moderate levels, driven partly by fast wind flowing from a coronal hole, which kept Earth's geomagnetic field between quiet and unsettled, Fox Weather reports.

A sharp drop from last year's peak#

The spotless stretch arrived as the sun moves away from the height of Solar Cycle 25, the current roughly 11-year rise and fall in activity that reached its maximum in late 2024, Fox Weather reports.

On Aug. 8, 2024, the sun recorded an estimated 337 sunspots in a single day, the highest daily count of Solar Cycle 25 and the highest daily estimate from NOAA's Space Weather Prediction Center since March 2001, according to Fox Weather.

Sunspots are darker, cooler patches on the sun's surface caused by concentrations of magnetic flux that block the rising heat known as convection, and their numbers rise and fall over the same roughly 11-year cycle, according to Wikipedia.

Reading the sun's older cycles#

Researchers Kristof Petrovay, Laura G. Magyar and Hisashi Hayakawa used centuries-old records of aurorae, the glowing sky displays produced when solar particles strike Earth's atmosphere, to reconstruct eight solar activity cycles between 1560 and 1640, according to a study in Scientific Reports reported by the Times of India.

The Times of India notes that aurora sightings are an imperfect stand-in for direct sunspot counts, since low-latitude aurorae are rare and tend to mark only the strongest space-weather events, which is why the researchers built a statistical method to pull cycle information from those sparse historical sightings.

Discover more