Sun

Sun officially reaches solar maximum in its 11-year cycle


NASA and NOAA said this week that the sun has officially reached Solar Maximum, the peak of its 11-year cycle. NASA heliophysicist C. Alex Young and EarthSky’s founder Deborah Byrd talked about it on this week’s Friday livestream, our Sun News of the Week. Watch in the player above, or on YouTube.

  • NOAA and NASA announced solar maximum has arrived. Solar maximum is the peak of activity in the sun’s 11-year solar cycle.
  • Signs of the peak of the sun’s cycle include the magnetic poles flipping and a high number of sunspots on the sun’s surface.
  • We can still expect to see more aurora in the months to come. Scientists won’t know the exact month of the peak and its length until they look back on the data.

NASA published this original story on October 15, 2024. Edits by EarthSky.

We’re at the peak of the 11-year solar cycle

In a teleconference with reporters on Tuesday, October 15, 2024, representatives from NASA, the National Oceanic and Atmospheric Administration (NOAA) and the international Solar Cycle Prediction Panel announced that the sun has reached its solar maximum period, which could continue for the next year.

The solar cycle is a natural cycle the sun goes through as it transitions between low and high magnetic activity. Roughly every 11 years, at the height of the solar cycle, the sun’s magnetic poles flip. On Earth, that’d be like the North and South poles swapping places every decade. And the sun transitions from being calm to an active and stormy state.

NASA and NOAA track sunspots to determine and predict the progress of the solar cycle … and ultimately, solar activity. Sunspots are cooler regions on the sun caused by a concentration of magnetic field lines. Sunspots are the visible component of active regions. These are areas of intense and complex magnetic fields on the sun that are the source of solar eruptions.

Jamie Favors, director of the Space Weather Program at NASA Headquarters in Washington, said:

During solar maximum, the number of sunspots, and therefore, the amount of solar activity, increases. This increase in activity provides an exciting opportunity to learn about our closest star. But it also causes real effects at Earth and throughout our solar system.

Side-by-side images of 2 suns, on the left a blank surface and on the right lots of dark spots at solar maximum.
Here’s a comparison of the sun at solar minimum, from December 2019, and solar maximum, from May 2024. Image via NASA/ SDO.

Solar activity leads to space weather

Solar activity strongly influences conditions in space known as space weather. This can affect satellites and astronauts in space, as well as communications and navigation systems – such as radio and GPS – and power grids on Earth. When the sun is most active, space weather events become more frequent. Solar activity has led to increased aurora visibility and impacts on satellites and infrastructure in recent months.

During May 2024, a barrage of large solar flares and coronal mass ejections (CMEs) launched clouds of charged particles and magnetic fields toward Earth, creating the strongest geomagnetic storm at Earth in two decades. And it was possibly among the strongest displays of auroras on record in the past 500 years.

Elsayed Talaat, director of space weather operations at NOAA, said:

This announcement doesn’t mean that this is the peak of solar activity we’ll see this solar cycle. While the sun has reached the solar maximum period, the month that solar activity peaks on the sun will not be identified for months or years.

When is the exact peak of solar maximum?

Scientists will not be able to determine the exact peak of this solar maximum period for many months because it’s only identifiable after they’ve tracked a consistent decline in solar activity after that peak.

However, scientists have identified that the last two years on the sun have been part of this active phase of the solar cycle. That’s due to the consistently high number of sunspots during this period. Scientists anticipate the maximum phase will last another year or so before the sun enters the declining phase. And that leads back to solar minimum. Since 1989, the Solar Cycle Prediction Panel – an international panel of experts sponsored by NASA and NOAA – has worked together to make their prediction for the next solar cycle.

Solar cycles have been tracked by astronomers since Galileo first observed sunspots in the 1600s. Each solar cycle is different. Some cycles peak for larger and shorter amounts of time, and others have smaller peaks that last longer.

Chart with jagged up and down lines from the 1700s to now.
This is the sunspot number over the previous 24 solar cycles. Scientists use sunspots to track solar cycle progress. The dark spots are associated with solar activity, often as the origins for giant explosions. For example, solar flares or coronal mass ejections are giant explosions that can spew light, energy and solar material out into space. Image via NOAA’s Space Weather Prediction Center.

Solar maximum is slightly exceeding expectations

Lisa Upton, co-chair of the Solar Cycle Prediction Panel and lead scientist at Southwest Research Institute in San Antonio, Texas, said:

Solar Cycle 25 sunspot activity has slightly exceeded expectations. However, despite seeing a few large storms, they aren’t larger than what we might expect during the maximum phase of the cycle.

The most powerful flare of the solar cycle so far was an X9.0 on October 3. (X-class denotes the most intense flares, while the number provides more information about its strength.)

NOAA anticipates additional solar and geomagnetic storms during the current solar maximum period. This will lead to opportunities to spot auroras over the next several months, as well as potential technology impacts. Additionally, though less frequent, scientists often see fairly significant storms during the declining phase of the solar cycle.

Graph showing a bell curve and plotted points on the first half of the curve extending high above the predicted peak.
The Solar Cycle 25 forecast, produced by the Solar Cycle 25 Prediction Panel, which is co-chaired by NASA and NOAA. Sunspot number is an indicator of solar cycle strength. The higher the sunspot number, the stronger the cycle. Image via NOAA’s Space Weather Prediction Center.

Future of space weather prediction

NASA and NOAA are preparing for the future of space weather research and prediction. In December 2024, NASA’s Parker Solar Probe mission will make its closest-ever approach to the sun, beating its own record of closest human-made object to the sun. This will be the first of three planned approaches for Parker at this distance, helping researchers to understand space weather right at the source.

NASA is launching several missions over the next year that will help us better understand space weather and its impacts across the solar system.

Space weather predictions are critical for supporting the spacecraft and astronauts of NASA’s Artemis campaign. Surveying this space environment is a vital part of understanding and mitigating astronaut exposure to space radiation.

NASA works as a research arm of the nation’s space weather effort. To see how space weather can affect Earth, please visit NOAA’s Space Weather Prediction Center, the U.S. government’s official source for space weather forecasts, watches, warnings, and alerts.

Bottom line: NASA and NOAA announced on October 15, 2024, that the sun has reached the peak of its 11-year solar cycle, or what is known as solar maximum.

Via NASA

Keep up-to-date with solar activity via our daily sun post!

Posted 
October 16, 2024
 in 
Sun

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