Solar System

New Forecast Resets Solar Cycle Expectations

A new forecast suggests that sunspot numbers, aurorae, and other solar activity will peak sooner and at a higher level than expected.

Solar System

The Sun Gets Its Close-up: Images from New Solar Telescope

The Daniel K. Inouye Solar Telescope shows some stunning detail on the Sun, including sunspots, fibrils, granules, and other solar textures.

Celestial News & Events

See a Giant Sunspot!

If you have a solar filter, check out the sunspot group AR 3190 that's crossing the solar disk this week.

solar flare

Solar System

The Sun Is Waking Up — Right On Schedule

The Sun is ramping up activity, but contrary to some reports, this solar cycle is still consistent with scientists' predictions.

Naked eye sunspots

Explore the Night with Bob King

How to Observe and Measure Naked-eye Sunspots

As Solar Cycle 25 ticks up, naked-eye sunspots are becoming more frequent. They're not only fun to observe, but with this simple method you can determine just how big they are. We also have news on a bright supernova!

Sunspot, in detail

Solar System

Will the Next Solar Cycle Surprise Us?

The coming months will test a new prediction that — contrary to most expectations — forecasts one of the strongest sunspot cycles on record.

Sunspots at solar minimum vs. maximum

Solar System

The Sun’s Activity Cycle Is Stabilizing

Solar Cycle 25 is here, and forecasts suggest the next decade of the Sun’s activity will mimic the last one — halting a 40-year trend.

Celestial News & Events

Giant Sunspots, Flares Presage Arrival of Solar Storm

Two big, naked-eye sunspot groups are putting on a splendid show this week. We're also in the crosshairs for a strong geomagnetic storm and possible auroras.

Spotless Sun

Stellar Science

Is Our Sun Slowing Down in Its Middle Age?

The Sun, now halfway through its life, might be slowing its magnetic activity, which could lead to permanent changes in the sunspots and auroras we see.

Magnetic manifestations

Explore the Night with Bob King

Fun in the Sun: A White-Light Guide to Our Nearest Star

We examine the fascinating solar phenomena that anyone with a small scope and safe solar filter can see, whether the Sun's in eclipse or not.

Celestial News & Events

The Spotless Sun

The Sun has been unusually quiet lately. Since the start of 2017, only a single tiny sunspot has made a brief appearance on the solar disk.

active region 1520

Stellar Science

How Astronomers Count Sunspots

A multi-year investigation revealed errors in our understanding of the Sun.

Faculae along solar limb on July 18, 2014

Explore the Night with Bob King

Blank Sun? Faculae to the Rescue!

Fascinating faculae provide a way for anyone with a small telescope to track the ups and downs of the solar cycle — even when there are no sunspots.