From "solar maximum" to "minimum" in one week

The number of sunspots changes with about 11 year cycles, and Sun is on the declining phase of its cycle 25. However, the solar activity may vary significantly even on a shorter time scales. Nine days ago (8 Aug. 2025, left) there were number of sunspots located mostly in the Northern hemisphere (upper part of the solar disk). This level of activity is typical for a solar maximum. However, today (17 August, 2025, right) there are only very few small pores situated mostly in the Southern hemisphere. Such low sunspot activity is more typical for the period of solar minimum. Why does it matter? The ultraviolet (UV) flux, which strongly correlates with sunspot activity, heats the Earth atmosphere. More sunspots mean the Earth’s atmosphere expands to higher altitudes, where it creates additional drug for low-Earth orbit (LEO) satellites. Such swings in number of sunspots may result in more LEO satellites being prematurely lost due to space weather. 

GONG H-alpha data transfer incident resolved

Saturday morning (16 Aug), one of NISP web servers stopped, and it did not auto-recover on-time. This delayed the transfer of H-alpha data between NISP to NOAA/SWPC data centers. The team was informed about the issue, and worked remotely on resolving it. As of 10:40 am (local time) the issue was resolved, and the flow of data to NOAA/SWPC was restored. GONG magnetogram data transfer were not impacted by this incident. 

GONG data processing update

Processing of the network-merged daily velocity and magnetogram images, p-mode-coefficient time series, and ring-diagram analysis products for GONG month 305, and the p-mode frequency data products for central GONG month 304 is completed and the data products are now available. 

Formation of an active region

 

See formation of an active region as observed by GONG (video created by Niles Oien) - https://gong2.nso.edu/products/misc/devGallery/viewSingleEvent.php?eventDir=event_20250802

 

GONG/BB - Power Outage

 A notification was posted on the BVES website regarding the outage:

 

Southern California Edison (SCE)- Restoration and Continued Public Safety Power Shutoff Warning August 4, 2025

Bear Valley Electric Service (BVES) is notifying customers that Southern California Edison (SCE) has restored power from the Public Safety Power Shutoff (PSPS) affecting BVES supply lines. Power restoration typically takes 8 hours. Southern California Edison (SCE) has placed one of the supply lines on standby for re-energization due to a nearby fire.

Additional period of concern begins August 5th, at 12:00 p.m. until 9:00 p.m. If SCE de-energizes this line, BVES customers will not experience an outage due to redundancy in the transmission lines. However, this condition does create the potential for large scale outages should one of the other transmission lines experience an outage during the PSPS event.

This precaution is mainly due to high winds and aims to reduce wildfire risk. Power restoration typically takes 8 hours and will start after the wind subsides. Delays may occur if daylight is required for safe inspections.

Bear Valley Electric Service (BVES) is reaching out to customers who may be impacted if Southern California Edison (SCE) implements a Public Safety Power Shutoff (PSPS). Updates will be provided through Facebook, voice and text messages, www.bvesinc.com, and local media.

As a reminder, the State of California allows electric utilities like SCE to proactively shut off power in high-risk areas during extreme weather conditions to reduce wildfire risk and ensure the safety of customers, their families, and property.

 

Also of note is the developing Gold Fire that is located north of Big Bear in the Holcomb Valley. 

 

 

 

Cycle 25 progression as observed by GONG magnetographs

 Time vs. solar latitude diagram of the radial component of solar magnetic field for 2006-2025. Each column represents one solar rotation (Carrington map). Blue/red show negative/positive polarity fields scaled between ±5 Gauss. Mid-latitude ( ±30 degrees) patters in both hemispheres correspond to the solar active regions. As solar cycle progresses, the latitude of active region formation drifts from higher to lower latitudes. Originating from these active region belts are diffused patterns drifting towards the solar poles. These are the remnants of trailing polarity fields of active regions, so called poleward surges, which gradually cancel out the polar fields of previous cycle and build-up new polar field of next solar cycle. In active regions, the leading polarity field is typically stronger, and it is more compact in comparison with the following polarity field. Also, the sign of the leading polarity fields in active regions is the  hemisphere and cycle dependent (so called, Hale polarity rule). This explains the sign-asymmetry in active region belts on this map: in cycle 24, the mid-latitude belt in the northern hemisphere appears mostly positive, while in the southern hemisphere, it is mostly negative. This polarity sign-preference reverses for cycle 25 with the mid-latitude belt in the northern/southern hemisphere appearing mostly negative/positive. The active region belts represent the 11-year (sunspot) cycle, which when combined with the sign-reversal of leading polarities of active regions in consecutive cycles (the Hale polarity rule) and the polar field evolution forms a 22-year magnetic cycle of the Sun. Data are acquired by GONG instruments operated by NISP/NSO/AURA/NSF.