We understand that the sun has actually entered its peak stage of activity, called solar optimum. Are we still in it, or is solar optimum currently behind us? Let’s see what the information needs to state.

We can not see it with our bare human eyes, the sun is extremely vibrant. On the sun’s surface area, areas of focused electromagnetic fields manifest themselves as dark sunspots. Above sunspots, active areas in the sun’s environment produce solar flares and coronal mass ejections (CMEs ), both of which can affect Earth through area weather condition.

The frequency of sunspots, solar flares and coronal mass ejections is not continuous. Rather, it fluctuates throughout an 11-year solar cycle. At the bottom of this solar cycle, called solar minimum, months can pass without a single sunspot. At the peak of the cycle– called solar optimum — sunspots, flares and CMEs are prevalent.

We have actually tracked solar cycles for centuries by counting the variety of sunspots on the sun. Given that December 2019, at the solar minimum marking completion of Solar Cycle 24, we have actually remained in Solar Cycle 25. Cycles usually last around 11 years, however the precise period in between subsequent solar minimums differs from cycle to cycle.

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At the start of Solar Cycle 25, the National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center released its main solar cycle forecast, based upon approximately forecasts from the clinical neighborhood. The forecast prepared for that a solar optimum peak of 101.8 to 125.2 regular monthly sunspots would happen near July 2025.

Solar Cycle 25 has actually currently gone beyond the forecasted peak, reaching a 13-month smoothed month-to-month worth of 156.7 in August 2024. The 13-month smoothed worth of an offered month is figured out by the average of the particular month, with 6 months on each side of it (reaching 13 months overall). There is a six-month lag up until this worth is readily available, with August 2024 being the most current information point as of March 2025.

This smoothed worth will likely continue to increase, however it likewise depends upon the sunspot amounts to in the coming months. It is the peak of this 13-month smoothed curve– not the greatest private month– that figures out the peak of the solar cycle.

The chart above screens the solar cycle advancement from 2010 to present. The black line reveals regular monthly sunspot worths, and the purple represents the smoothed average. From this chart, we can see that Solar Cycle 25 (from 2019 to present) has actually currently surpassed the size of Solar Cycle 24.

The biggest specific sunspot month of the cycle up until now, August 2024, had a sunspot overall of 216. Ever since, regular monthly overalls have actually been much lower, varying from 136 to 166 in between September 2024 and March 2025. Is this an indication that solar optimum has currently passed? Perhaps, however possibly not.

The NOAA Space Weather Prediction Center has a speculative solar cycle forecast chart that’s presently openly offered in its online testbedThis speculative forecast is a rolling one; it updates monthly as the most current month of information appears. Due to the fact that it is used updated information, and not a forecast from before any solar cycle information was offered, it is much more precise than the 2019 forecast– and maybe the most precise predictor we have for the rest of the solar cycle.

The most current variation of this forecast, which was upgraded in March 2025, exists listed below. Per this existing forecast, solar optimum has probably currently passed, with a peak in between August and November 2024. If this holds true, then we might currently remain in the decreasing stage of Solar Cycle 25.

This solar optimum date is extremely various from the initial forecast of July 2025. How can this be? Not all solar cycles are precisely 11 years in length. In basic, the bigger the solar cycle, the much shorter it is. Due to the fact that the amplitude of our present cycle has currently far went beyond the anticipated peak, it is for that reason most likely that the real solar optimum date will likewise precede the initial forecast.

Is that it, then? Has solar optimum currently reoccured? Possibly not. Recalling to the very first solar cycle chart displayed in this post, we see that Solar Cycle 24 had 2 peaks– one in 2012, and a 2nd in 2014. This double peak seldom includes in forecasts, however it has actually been observed often times throughout historical solar cycles. Could Solar Cycle 25 show a 2nd peak, postponing solar optimum till later on in 2025? It is definitely possible, although some might argue that we’ve currently experienced 2 peaks, in 2023 and 2024, respectively.

These peaks are not as plainly separated as in previous solar cycles, however they do produce a clear inflection in the smoothed solar cycle curve. Eventually, we will need to wait another year or two to understand when the real peak of the solar cycle took place.

Even if the particular regular monthly peak of the cycle has actually passed, it does not imply solar activity is over. Strong solar activity continues for a year or 2 beyond the optimum date, so we still have a long time to delight in sunspots, coronal mass ejections, and any geomagnetic storms and aurora programs related to them.

Initially published on Space.com

Sun test: How well do you understand our home star?

Dr. Ryan French is a solar physicist, science communicator and author. He is pursuing the secrets of the sun at the leading edge of contemporary solar physics research study, utilizing innovative telescopes on the ground and in area. Ryan likewise works to share the marvels of the sun and area with the general public, through museums and observatories, tv, and social networks on Twitter and TikTok. Ryan’s very first book, “The Sun: Beginner’s guide to our local star” was released in 2023.