Solar activity, manifested primarily through sunspots, solar flares and coronal mass ejections, has long influenced both the near-space environment and terrestrial systems. Over millennia, variations ...

The Sun seems like a perfectly reliable, unchanging presence in the daytime sky, but it’s not. Intense heat and pressure in its core fuses hydrogen atoms into helium, fueling the cosmic fire that ...

Here’s what you’ll learn when you read this story: The intensity of the Sun’s activity ebbs and flows across years, but also across decades—a behavior that scientists haven’t quite figured out yet. At ...