Solar Activity Report: October 26 - November 1, 2026

Solar activity remained at low levels throughout the reporting period, with only about ten low-intensity C-class flares observed. Most of these flares originated from a newly emerged active region near the southwest limb early in the week. NOAA designated this region as AR 14561, and it rotated onto the far side of the Sun on October 28 after crossing the west limb. The region produced the strongest event of the week, a C2.8 flare on October 26. None of the flares were associated with Earth-directed CMEs. However, a filament eruption on the visible disk generated a CME that resulted in a glancing geomagnetic impact at Earth, producing auroral activity on October 30-31.

The latest helioseismic maps reveal a small number of active regions on the Sun's far side. If these regions persist, some may rotate into the Earth-facing hemisphere towards the end of the week.

Update on access to NISP data

The NISP PHP instances have been upgraded. The firewall restrictions reported in earlier post were lifted, and the access should be back to normal. Please direct questions to nispdata@nso.edu.

Solar Activity Report: October 19 - 25, 2026

 Solar activity continued to decline as the current solar cycle progressed through its declining phase. Activity levels remained low throughout most of the reporting period, with the exception of October 19, when Active Region 14551, located in the southwestern quadrant of the solar disk, produced an M1.6 flare, temporarily elevating activity to moderate levels. This was the strongest event recorded during the week. Several low-intensity C-class flares were also observed throughout the reporting period. By the end of the week, nearly all numbered active regions had rotated onto the far side of the Sun, leaving the Earth-facing disk largely devoid of significant activity.  The attached figure displays three sample images obtained at the Big Bear GONG site on October 25, toward the end of the reporting week. No Earth-directed coronal mass ejections (CMEs) were detected during this period.

Analysis of recent far-side helioseismic maps suggests the emergence of a new moderate-sized active region in the northern hemisphere. Based on its current location, the region is expected to rotate onto the visible solar disk around October 30.

GONG observations for scientific research, operational space weather forecast, and public use

In 1995, GONG started its operations as a 3-year project aimed at investigating the internal structure and dynamical behavior of the Sun through the analysis of solar oscillations (so called, helioseismology). Over the years, GONG observations were used by several generations of scientists to study the parameters of the acoustic modes, and their variations over time and space. Accurate knowledge of variability of these parameters within the solar interior is essential for understanding the origins of magnetic activity and for constraining solar dynamo models. One of the early results of helioseismology using GONG data was the determination of the internal profile of the solar rotation rate as a function of depth. In particular, the sharp transition from differential to solid-body rotation, termed the tachocline, was discovered at the base of the convection zone (about 200,000 km below solar visible surface). Later, a thin shear layer in the rotation rate immediately below the solar surface was detected. The latter is referred to as the Near-Surface Shear Layer (NSSL), or leptocline.

While the line-of-sight (LOS) magnetograms were produced by GONG from the beginning of the project, it was not until 2001, when the magnetograms from the upgraded GONG++ saw the extensive use for studying magnetic properties of the Sun, their changes with the flare activity, solar cycle, modeling of coronal and interplanetary magnetic field, and solar wind.  In 2010, GONG was also upgraded to take observations in hydrogen H-alpha spectral line. 

GONG data continue to be extensively used by the research communities both in U.S. and abroad. See this post for highlights of scientific discoveries and early GONG history.  The data are now used operationally by the National Oceanic and Atmospheric Administration (NOAA) Space Weather Prediction Center (SWPC), the space weather prediction center of U.K. MetOffice, and in other countries (e.g. Japan, South Korea).  For space weather awareness, GONG data are included in the analyses of NASA’s Moon-to-Mars office. GONG observations are downloaded for modeling of solar wind and solar eruptive events by the US university groups, research organizations in Europe, and Community Coordinated Modeling Center (CCMC) operated by NASA. Data is used for predicting the magnetic connectivity between the solar surface and NASA’s Parker Solar Probe (PSP) during its closest (perihelia) approach to the Sun. Farside images derived from GONG data are used for predicting future sunspot activity on Earth, and the appearance of sunspots on farside when observed from the EU's Solar Orbiter, or from a rover on Mars surface.

GONG observations are also used widely by amateur astronomers to provide a reference and overall guidance for their observations. “The GONG Show” depicting H-alpha and white light images are posted regularly on the amateur astronomy website at https://www.cloudynights.com/. As one example, we show image  reproduced from Sun Ha Session, 2026-04-29 (Frank Lothar Unger) - AstroBin  that uses GONG full disk image as a reference.

GONG data has been incorporated into several apps both for scientific research communities and for public.  This includes the Solar-MACH, a web-tool widely used in the heliospheric community. It obtains, among others, GONG magnetograms using sunpy's fido functionality to use them for the Potential Field Source Surface (PFSS) modelling. The Solmate (solmate.nz), a space weather dashboard for New Zealand, employs a Filament Tracker to highlight filaments on GONG full-disk H-alpha images and watch for eruptions that might send a CME towards Earth. In Australia, an amateur astronomer is working on a project that incorporates GONG H-alpha full-disk images in his star atlas application. Recently, FaktPocasi.cz, a free Czech weather and space-weather website contacted GONG project about their plans to display current GONG observations on their site with additional explanations in plain language of what is happening on the Sun.

Currently, two public competitions are using GONG observations. One is hosted by the Frontier Development Lab (FDL) https://fdl.ai/benchlab-solar-wind-prediction-2026, and is concentrated on prediction of solar wind using magnetograms from different instruments including GONG. The other, Kaggle competition "Solar Filament Segmentation Challenge 2026" is one of seven IEEE Big Data Cup 2026 Data Challenges at the Frontier of AI, Science & Society, https://bigdataieee.org/BigData2026/cup/. It aims at the proper segmentation of solar chromospheric filaments using GONG H-alpha images.

 

Limited Access to NISP Data and Websites

Due to the recent PHP vulnerability, NISP data and web sites are available with limited access.  General public access is restricted until the vulnerability can be mitigated.  Please direct questions to nispdata@nso.edu.

Solar Activity Report: October 12 -18, 2026

 Solar activity remained predominantly at low levels throughout the reporting period, except on 16 October, when activity briefly reached moderate levels following an M1.3 flare from active region 14551, the largest event of the week. During the remainder of the period, activity was characterized by persistent C-class flaring, including several mid intensity C-class events By the end of the week, the majority of active regions had rotated into the western hemisphere, leaving the eastern hemisphere largely devoid of sunspots. This is clearly visible in the accompanying images from the Big Bear Solar Observatory, which show the magnetogram obtained at the end of the week. No Earth-directed coronal mass ejections (CMEs) were observed during this period.

Current helioseismic far-side maps do not reveal any major active regions that are expected to rotate onto the Earth-facing hemisphere within the next few days.

GONG Network in an Extended Low Duty Cycle Phase

GONG operates as a ground-based network of six observing stations distributed around the globe. Although the network routinely provides high-cadence observations with an exceptionally high duty cycle, periods of reduced coverage occasionally occur. The duty cycle can be adversely affected by several factors, including instrument malfunctions at one or more sites, scheduled maintenance activities, and unfavorable weather conditions.

For more than two weeks, GONG has been experiencing persistently low duty cycles, as illustrated in the attached figure. Large gaps in daily coverage are readily apparent. It appears that the ongoing strong El Niño conditions have been contributing to severe weather at two of the network's sites, Big Bear (USA) and Cerro Tololo (Chile), resulting in significant impacts on GONG observations.

The Mauna Loa (Hawaii) site remains offline following the volcanic eruption of late November 2022 and has not yet returned to operational status. In addition, the Learmonth (Australia) site is currently non-operational due to a technical issue. Consequently, the Udaipur (India) and El Teide (Spain) stations have been providing the majority of the network's observations during this period.

The reduced duty cycle has a direct impact on the quality and availability of GONG data products. In particular, when the duty cycle falls below approximately 80%, the far-side helioseismic maps become increasingly noisy and unreliable. Consequently, these maps may not be generated during periods of insufficient data coverage.

NISP produces far-side maps twice each day using GONG Doppler observations to identify active regions and emerging magnetic activity on the far side of the Sun. As a key space weather data product, these maps provide advance warning of potentially active regions before they rotate into Earth view, thereby supporting operational forecasting and mitigating space weather risks.

ngGONG Chilean site visit

This week, October 11-16, 2026, the NSF's National Solar Observatory team traveled to Chile to investigate future locations of second NSO's ngGONG station. Several sites at Cerro Tololo and Cerro Pachón were visited. Attached images show NSO and NOIRLab/CTIO team members at different locations considered for ngGONG station (Photos 1 and 2); the current location of GONG  at Cerro Tololo (photos 3 and 4); the road sign between Cerro Tololo and Cerro Pachón (photo 5). CTIO is also considered as a location for future COronal Solar Magnetism Observatory (COSMO) by High Altitude Observatory (HAO). Photo 6 shows a site-testing solar telescope (SDIMM) at COSMO location.

ngGONG, the next generation Groundbased Solar Observing Network, is a future 6-site network that will replace the aging GONG and enhance its capabilities to include full-vector field observations at different heights in the solar atmosphere, photospheric and chromospheric Doppler velocity imagers, helioseimic and sun-as-a-star instruments. Some stations will be equipped with coronagraphic instruments. The design of ngGONG is funded by the US National Science Foundation as a three year project (Oct 2025-Sep 2028). 

 

Solar Activity Report: October 5 - 11, 2026

 Solar activity varied substantially during the reporting period, rising from low to high and then returning to low levels. Such variability is typical of the declining phase of the solar cycle, when sudden bursts of enhanced activity are common. Approximately 50 C‑class and 7 M‑class flares were observed, with most originating from active region 14549. The strongest event was an M6.7 flare on October 8 from this region, followed by another high‑energy M6.4 flare on October 10.

Other M‑class flares were of lower intensity: an impulsive M1.0 flare from active region 14545 on October 5; M1.4 and M1.8 flares from active region 14549 on October 6; an M1.3 flare from active region 14547 on October 9; and an M1.2 flare from active region 14549 on October 10. All of these active regions were located in the northern hemisphere, which was more active than the southern hemisphere during this period. The X‑ray flux remained near the B/C‑level boundary. The quietest day of the week was October 11, when the flux stayed predominantly in the B‑level. Several CMEs were originated from these flares, some with Earth‑directed components.

ngGONG developments

Last week, Sep 30-Oct 1, 2026, the NSF's National Solar Observatory team traveled to the Big Bear Solar Observatory (BBSO) in California to discuss future location of one of NSO's ngGONG stations. ngGONG, the next generation Groundbased Solar Observing Network, is a future 6-site network that will replace the aging GONG and enhance its capabilities to include full-vector field observations at different heights in the solar atmosphere, photospheric and chromospheric Doppler velocity imagers, helioseimic and sun-as-a-star instruments. Some stations will be equipped with coronagraphic instruments. The design of ngGONG is funded by the US National Science Foundation as a three year project (Oct 2025-Sep 2028). Attached image shows the NSO and BBSO/NJIT team members at the approximate location of future ngGONG station. The site is located on the shore of Big Bear Lake between GONG and SOLIS stations. 

Solar Activity Report: September 21 - 27, 2026

 Solar activity remained at low levels during the reporting period, with X‑ray flux generally at mid‑B levels except for a few impulsive, low C‑class flares. Several active regions were present on the visible disk, but most remained relatively quiet, producing little to no significant flaring activity aside from occasional low‑intensity C‑class events. The strongest flare was an impulsive C3.1 event on September 26 from the active region 14534, located near the north-west quadrant. No Earth‑directed CMEs were identified in available coronagraph imagery.  

The most recent helioseismic map of the far side shows no evidence of significant active regions that are likely to rotate onto the Earth‑facing hemisphere over the next few days.

GONG at Udaipur is back on line

The report from India received on 24 Sep. 2026, indicated that "the sky continues to be clear and favorable for observations since last couple of days. Hence we would like to resume UDGONG observations".  Following to this, the startup procedure was sent to the local support staff. The turret was unstowed early today (25 Sep 2026). The instrument and data computers were rebooted, and GONG/UD station came on-line. Indian monsoon is over! Attached image is one of the first H-alpha images taken after the monsoon.

Time-domain Astronomy

With the NSO team moving the archive of the NSO at Sac Peak historical data to Colorado this week, one may ask the questions of "why do we need to preserve old data" and "what can be learned from it"?

Recent article by Dr. Hisashi Hayakawa and his co-authors highlights the importance of historical data for studying past solar activity. They found that the observations of solar eclipse on 13 May 1733 by Swedish astronomer and mathematician Birger Wassenius may have been the very first observations of so-called rush-to-the-poles prior to the solar polar field reversal. These Wassenius ' observations also suggest that in 1733, the Sun was not in an activity minimum as previously thought. The article was highlighted by the AAS Nova in A New Look at a Centuries-Old Solar Eclipse.

 

Solar Activity Report: September 14 - 20, 2026

 Solar activity during the reporting period remained in the very‑low to low range. At the beginning of the week, all named active regions were clustered in the western hemisphere, leaving the eastern hemisphere without sunspots. Around September 19, new active regions began to appear on the east limb, raising the activity level into the low category. Active region 14535, rotating into the Earth‑facing hemisphere, produced the first C‑class flare of the week (C3.3) along with a few additional low‑intensity C‑class flares. In addition, active region 14534 generated the strongest event of the week, a C3.7 flare, while positioned near the central meridian in the northern hemisphere. No Earth‑directed CMEs were observed. 

Helioseismic imaging of the Sun’s invisible hemisphere shows no evidence of any major active regions expected to rotate onto the visible disk in the coming week.

Sacramento Peak Observatory

This week, NSO staff will pack the remaining materials from the photographic archive and some other locations at (former) NSO at Sac Peak Observatory. This represents the end of golden era of solar research at the Sacramento Peak Observatory. The observatory is closed, and the site would be restored to its original (national forest) state. The events that led to this outcome include mercury leak discovered inside the Dunn Solar Telescope (DST) on Jan. 5, 2026.

Here is a very brief history of Sac Peak observatory. The reader can find more details in the following publications: (Bushnell, 1962; DeVorkin, 1983; Zirker, 1998; Ramsey, 2002; Liebowitz, 2002; CH2M HILL Inc., 2017 – see Solar Phys (2021) 296:3; https://doi.org/10.1007/s11207-020-01746-5 for complete references).

 

The need for a dedicated solar observatory was realized during World War II, when solar observations were used for predicting the impact of solar activity on radio communications.  

1947: 

• Menzel and Marcus O’Day of the Air Force team up to promote the idea of a second observatory to complement Climax and increase coverage. Same year, the US Air Force awards Harvard a contract for a site survey to select a location for a solar observatory. Subcontract is issued to the newly formed High Altitude Observatory in Boulder CO. Don Menzel of Harvard and Walt Roberts of HAO spearhead the Survey. As part of the Survey, Menzel and Roberts fly over many southwest mountains looking for a site and note Sacramento Peak.
• September: two resident observers begin data collection of observing conditions at Sacrament Peak 
• December: Menzel and Roberts tentatively recommend Sac Peak as site for new solar observatory

1948, April: 

• US Department of Defense (DOD) Research and Development board approves Sac Peak as final site, and Harvard/HAO awarded contract to develop the observatory.  

1949: 

• Harvard/HAO team starts observations with 11 cm (4.5 “) coronagraph on 2.4 m (8’) spar in a sliding roof observatory (Photo 1). Its primary function is a coronal activity monitor. Later same year, a Sears and Robuck grain bin was purchased and made into a rotating dome, named the Grain Bin Dome. 
• 3 m (10’) spar was added; a 15 cm (6”) prominence telescope is mounted on the 3 m spar
• Construction of a 40 cm (16”) coronagraph and 8 m (26’) spar begins in Boulder by Jack Evans and Walt Roberts (Lyot consulting on optics)
• Daily radio observations of the Sun begin (Cornell University). 

1950:  

• Sac Peak became known as the Sacramento Peak Station of the High Altitude Observatory jointly operated by Harvard University and the University of Colorado under contract from the Air Force (Photo 2).

1951:

• March: 6 cm (2.5”) Hydrogen Alpha Flare Patrol camera mounted on the 3 m spar in the Grain Bin and daily observations are started.  
• April: Sac Peak is established as the Upper Air Research Activity under the Air Forces Geophysics Research Division (later to become the Air Force Cambridge Research Laboratory). At that time, the observatory was  operated by a combination of military and civilian US Air Force employees.     

1952:    

• Jack Evans appointed superintendent of Sac Peak. 
• Renamed the Upper Air Research Observatory. 
• Evans hires Richard (Dick) Dunn
•  Construction of a new facility to house the 8 m spar and 40 cm coronagraph begins
• 15 cm white light telescope installed on the 3 m grain bin spar 
• Staff: Dunn, Evans (sup), J. Warwick, C. Warwick
• 10 Redwood houses built along the ridge to house staff, Main Lab office building completed and apartments to house visiting scientist

1953:

• New Facility (Big Dome) completed at Sac Peak and 8 m (26’) spar installed (Spar so well balanced only 2.5 mouse power required to drive right ascension, 1 mouse power = 1/10,000 horse power)
• 40 cm coronagraph installed on 8 m spar, used for both coronal and on disk measurements, used for the next 60+ years with some modifications.

1954:

• Cornell radio observations cease due to interference from Holloman AF Base    

1955:

• 13 m (43’) Littrow spectrograph installed in the Big Dome fed by the 40 cm coronagraph
• Helicopter landing strip built
• 38 cm (15”) chromospheric and prominence camera installed on the 8 m spar

1956

• Upper Air Research Observatory name changed to Sacramento Peak Observatory (SPO) and Jack Evans becomes its first director
• 1956 Staff: Dennison, Dunn, Evans (dir), Orrall, H. Smith,E. Smith, Zirker
• Dick Thomas, Grant Athay, John Jefferies were frequent visitors providing theoretical support

1957:

• Patrol coronagraph installed on Grain Bin Spar
• Universal Spectrograph installed in Big Dome
• Evans designs a telescope for Project Stratoscope, a balloon borne telescope flown my Martin Schwarzchild to measure solar granulation

1958:    

• Six Redwood Houses built on Sac Peak (previous housing was Quonset buildings)
• A concept for an evacuated solar tower telescope (VTT) is put forward to the Air Force

1959: 

• Spectroheliograph installed at the Big Dome 
• Development work on VTT begins

1960:    

• Coelostat and secondary mirror installed at the Big Dome feeding a 30 cm horizontal telescope providing a solar image to all instruments
• The road to Sac Peak is finally paved

1961:    

• SPO staff: Dunn, Dennison, Evans (director), Orall, H and E Smith, White, Zirker

1962:    

• 40 cm (16”) magnetograph telescope installed on the 8 m spar in the Big Dome along with a Doppler Zeeman Analyzer (DZA), Photo 3
• By 1962 there are 70 personnel working at SPO, 10 military, 28 civil service (7 PhDs) and 32 contractors. In addition, there are 12 visiting scientists

 

  

 

1963:

• Hilltop Dome constructed and a 3.6 m (12’) spar installed
• Grain Bin instruments (flare patrol and white light telescope) transferred to Hilltop
• Beckers and Simon join the SPO staff, H. and E. Smith leave

 

1964:

• Dick Dunn begins final design work begins on VTT
• Additional space for offices and film processing added to Big Dome

1965:

• Dunn designs a photoelectric flare spectrograph to measure flare emissions in 40 spectral lines

1966, Spring: 

• Construction starts on the VTT (Photo 4)
• 10 additional houses completed at Sac Peak, mainlab addition finished
• Photoelectric flare spectrograph install in Hilltop Lab and fed by innovative Gregorian heliostat, used by NASA for Skylab support

 

1967:    

• Dunn designs two photographic flare spectrographs, one for Hilltop and one for the 40 cm Coronagraph to make rapid measurements of flares
• Mainlab computing center developed (XDS Sigma 5) for data reduction

1969:

• VTT Completed with evacuated light path to remove internal telescope seeing, mercury bearings used to support telescope and separate mercury bearing to support the entrance coelestat.
• All SPO contractor personnel converted to civil service

1971:

• Photographic Eschelle Spectrograph installed in VTT

1973:

• Diode Array installed on the eschelle spectrograph
• Jacques Beckers designs a Universal Birefringent Filter which is installed at VTT, the UBF was tunable from 420 to 700 nm angstroms with a variable bandpass of 4 to 13 pm.

1974:

• Air Force notifies SPO of its intention to discontinue funding as a result of the Mansfield amendment in Congress
• AF contracts SPO to build the Solar Optical Observing Network (SOON) telescopes for the Air Force Weather Service
• Daily coronal patrol ceases operation
• 38 cm (15”) prominence telescope removed from Big Dome 8 m spar
• HAO closes Climax Observatory and begins construction of Stokes polarimeter and coronal emission-line photometer for installation at the Big Dome.

1975:

• First SOON telescope completed and installed in Hawaii
• Jack Evans steps down, Dick Dunn appointed director
• Nov 9: Goldberg informs the Association of Universities for Research in Astronomy (AURA) Executive Committee that the AF is divesting SPO
• NSF forms a blue-ribbon panel to determine fate of SPO chair by Martin Schwarzchild, the committee recommended positively, recognizing SPO as the premier solar facility both in the US and internationally

1976:

• July: NSF accepts responsibility for SPO on July 1st
• AURA agrees to serve as interim contractor for SPO operations
• Jack Zirker appointed acting director, AURA management begins
• Joint SPO and KPNO-Solar staffs discuss future directions of the observatories (Oscillations, Stokes Polarimetry, and Solar-Stellar connection seen as rewarding areas)
• Franz Deubner, using the NSF Dunn Solar Telescope at Sacramento Peak, demonstrates how solar five-minute oscillations are trapped inside the sun, leading to helioseismology

1976, November:

• start of Sac Peak K-line, sun-as-a-star observations in Ca II K-line on daily basis

1977:

• Stokes Polarimeter (STOKES I) installed in Big Dome (joint HAO/NSO project), uses the 40 cm coronagraph to measure on disk vector fields, single point detector. 
• K Coronagraph Emission Line Photometer (KELP) installed in Big Dome (joint HAO/NSO project), measures coronal fields in the plane of the sky
• Special Advisory committee to NSF with Art Walker chair, recommend that NSF continue SPO as a national observatory with visitor support and strong staff research.
• NSF solicits proposal to operate SPO
• Ray Smartt begins development of One-Shot coronagraph

1978:

• AURA discusses their proposal for SPO at the annual meeting
• April: AURA awarded contract for SPO (NSF contract 78-17292), AURA now has separate contracts for KPNO, CTIO and SPO
• Jack Zirker appointed director with a 5 year term
• Oct: First AURA visiting committee visits SPO
• Tim Brown and Jacques Beckers develop concept for a Fourier Tachometer for measuring small (a few m/s) velocities in the solar atmosphere and construction of prototype begins (NSO/HAO)
• SPO assumes operation of 48” AF photoelectric telescope in Cloudcroft, NM and builds a new photometer under contract to the AF
• First rubber mirror image improvement experiments at VTT by U.C. Berkeley group – only for stellar images

1979:

• One-Shot coronagraph mounted on Hilltop spar (simultaneously views the entire corona out to two solar radii – hence One-Shot
• Real Time Atmospheric Compensation (RTAC) developed by Itek Optical Systems tested at VTT – demonstrates feasibility, but only on rare conditions, shows that first order image motion can be removed by fast mirror
• White Light Flare Polarimeter installed in Hilltop, observes white light flares in 4 continuum band passes to study energetics 
• STOKES II (STOKES I upgrade to 2-D detector)
• Deubner and UCLA co-workers produce the first estimate of the internal solar rotation using Sac Peak data

1980    

• First of three oscillation experiment to the South Pole (later, telescope became part of the Sac Peak Visitor Center exhibit)
• SOON Telescope system completed for the Air Force

 

1981: 

• 12 cm refractor white light flare patrol in Hilltop
• First detection of the mesogranulation on the sun using Sac Peak observations 

1987:

• The Big Dome at Sacramento Peak Observatory was officially rededicated and renamed the John W. Evans Solar Facility on August 18, 1987 

1989:

• First reflective coronagraph based on highly polished silicon mirror was developed at NSO and installed at Hilltop facility.

 

 

1990-92: 

• The Advanced Stokes Polarimeter was developed as a joint project between NSO and HAO. ASP begun operations at Sac Peak  in 1992.

1993:  

• First successful demonstration of solar adaptive optics system achieved with the Lockheed segmented mirror and a Shack-Harthmann wavefront sensor at Dunn Solar Telescope (DST, NSO/Sac Peak). This work laid a foundation to later development of low-order (1999), high-order (2004) adaptive optics system for NSO telescopes, and future multi-conjugated AO.

1995: 

• The development of the Precision Solar Photometric Telescope (RISE/PSPT) for providing full-disk images to allow detailed study of the total solar irradiance variation in three wavelength bands at various temporal scales. Three instruments were put into operations: the Osservatorio Astronomico di Roma (1996), the Mauna Loa Solar Observatory (1998), and NSO at Sac Peak (2000). 

1996:

• Initial design study for a solar telescope network to replace the existing Solar Observing Optical Network (SOON). The design was completed, and the group proceeded with building a prototype, Improved SOON or ISOON. 

1997: 

• The SOON telescope at Palehua, Hawai’i, was dismantled in April 1997 and shipped to Sacramento Peak for developing ISOON prototype

1998:

• The Vacuum Tower Telescope (VTT) at Sacramento Peak was renamed the Richard B. Dunn Solar Telescope on September 30, 1998. 

1999:

• Steve Keil became the director of the National Solar Observatory (NSO) in May 1999. He served in the role until July 2013 

2001: 

• First phase of the Diffraction-Limited Stokes Polarimeter (DLSP) is an upgrade of the Advanced Stokes Polarimeter). DLSP became a prototype of Spectropolarimeter (SP) on board of Japanize satellite Hinode. 

2002: 

• Establishment of the Advanced Technology Solar Telescope (ATST) design effort, which later became the NSF's Inouye Solar Telescope (DKIST) - the world's largest solar telescope.

2011:

• 1:250 million model of Solar System was constructed along the NM6563. Sign for the Sun was placed near the Sunspot Visitor Center, and signs  with the names of the planets located along the highway.

2015:

• Observatory/scientific  staff begun relocating to new NSO Headquarters in Boulder, CO
• On December 26, 2015, Sac Peak experienced a severe storm with heavy snow and high wind (80+ MPH). Over 30 trees were uprooted, which damaged several houses and power lines. Conditions were severe enough to require an evacuation of personnel from Sacramento Peak to Alamogordo. Electric power, heat, and network services were restored by January 5, 2016.

2021:

•  As part of the divestment, NSF donated relocatable houses to the White Sands Habitat for Humanity. Starting April, 2021, the houses were moved to the Alamogordo, NM (Photo 5). 

 

Photo 6 shows aerial photograph of the National Solar Observatory at Sacramento Peak taken on 16 November 2002. The locations marked by white numbers are (1) the Grain Bin Dome, (2) the Hill Top Dome, (3) the Evans Solar Facility, (4) Dunn Solar Telescope, (5) ISOON, (6) Sunspot Visitor Center, (7) the Main Lab and Machine Shop, (8) platform for site testing of future DKIST, (9) – telescope that was used on the South Pole for solar oscillations measurements. Background photo courtesy of Kit Richards.

 

 

Two large sunspots on the Sun

The solar activity continues decreasing as the Sun enters the declining phase of cycle 25. It may still produce large sunspots. One of such sunspots can been spotted without a telescope right now. Attached image taken by GONG station at Learmonth, Australia shows the approximate location of two large sunspots. Since these large sunspots can be resolved by a human eye, they are called "naked eye" sunspots.  The human vision varies from person to person, and so not everybody would be able to see all naked-eye sunspots. Before the invention of the telescope in the early 1600s, naked-eye sunspots were the only ones humans could see when the Sun was naturally dimmed by dense fog, horizon haze, or thick smoke from forest fires. These observations, recorded in chronicles, provide direct record of solar activity in the past. 

Warning: "Always use ISO-certified eclipse glasses or handheld solar viewers when observing the Sun to prevent serious eye damage. Regular sunglasses are not safe, and you should never look directly at the Sun without proper eye protection."  For additional tips of how to view the Sun safely, please see https://eclipse.aas.org/eye-safety.

 

 

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  316 covering the period 20260524 to 20260628, and the p-mode frequency data products for central GONG month 315 spanning 20260418 to 20260523 is completed and the data products are now available.

How space weather may impact our society

The impact  of solar activity on our technological society was presented in many scientific publications and popular books (see, for example, "Storms from the Sun" by Michael J. Carlowicz and Ramon E. Lopez, Joseph Henry Press, 2003). Reports by the National Research Council (Baker et al. 2009)  and the Lloyd’s Insurance company (Lloyd's 2013) indicated that extreme solar eruptions could cause catastrophic, multi-trillion (!) economic damages, with extended recovery time, not counting human costs (Oughton et al. (2017). The impact would affect a power distribution, transportation, communications, satellite infrastructure, aviation, and global positioning systems (Eastwood et al. 2017).  

See recent CNN article by Kasha Patel and Sam Hart to learn "where a massive solar storm could take down the US power grid". Timely prediction of solar storms and their arrival time to Earth may help mitigating their impact. Observations from GONG stations play important role in such modeling.

Solar Activity Report: August 24 - 30, 2026

Solar activity varied from very low to medium levels during the reporting period. Seven M‑class flares were recorded during the first three days, all originating from active region 14513, followed by a gradual decline to low activity. Peak activity occurred between midday August 24 and midday August 26, including the strongest event of the week - an M6.9 flare on August 25. In addition, several medium-to-high intensity flares were produced during this period. From August 27 onward, the Sun remained quiet, producing only a few low‑intensity C‑class flares through August 30.

Far side helioseismic maps reveal several active regions on the far hemisphere. While most exhibit a low likelihood of appearing on the visible disk, an active region (14507 from the previous Carrington rotation) has a moderate probability of rotating onto the front side. Provided it does not decay, it is expected to return to the Earth‑facing hemisphere on September 4.

Challenges in Access to NISP Data

The data server of the NSO Integrated Synoptic Program (NISP), which provides access to GONG and SOLIS data, has been recently impacted by extensive web scraping activity. Subsequent security measures have greatly improved access; however, there are still periods where the scraping activity slows down significantly the access for all users including the operational space weather and the research communities. We are considering changes to the data access via user registration services, but as a temporary solution, the data center has implemented a IP-based priority access list for selected stakeholders. If you experience issues with accessing NISP data, please contact the data center at nispdata@nso.edu.

One day in the life of a large filament

A large chromospheric filament was present in the solar Northern hemisphere for several days. First, it could be spotted on 24 August 2026, as a prominence above the Eastern limb. Full disk image taken by GONG/Learmonth (Australia) shows this filament (circled) at the start of 30 August 2026. Later that day, the filament became active, and it disappeared. Filament eruptions are commonly associated with the coronal mass ejections (CMEs), but the coronal observations from SOHO/LASCO and GOES-19/CCOR-1 do not show an indication of a CME associated with this filament disappearance.  Nor there is an indication of a coronal blast wave in SDO/AIA observations (called Moreton wave, when observed in the chromosphere), which is another signature of a CME. Attached video shows the disappearance of this filament as observed throughout the day by GONG stations in Learmonth (Australia), Teide (Canary Islands), and Cerro Tololo (Chile). Video starts at about 00:00 UT, and it ends at 16:57 UT.  Transition between the instrument/sites is clear from changes in quality of the video. To reduce the size of video, the cadence is reduced from 1 minute to 4 minutes. GONG images can be accessed via the instrument website.

 

 

 

Small filament eruption, but no CME

GONG CT (Chile) station is back on line, and it produces great data! Starting at about 13:15 UT on 22 August, 2026, a small filament in the south-eastern solar hemisphere begun activating. Attached image shows location of the filament by a blue oval as observed by GONG/CT (Chile).  Coronal images from SDO/AIA (right side of the figure) indicate some restructuring taking place in the location of filament. The filament erupted and disappeared from H-alpha images at about 20:38 UT. Coronagraphic images did not show any sign of a CME associated with this filament eruption. There were two small coronal holes located East and South of the eruption site, and their walls might have deflected the filament eruption. Small chromospheric brightennings briefly observed south of the filament after its eruption may indicate the material falling back to the surface. This evolution is shown in the attached video.

Flare, CME and postfare loops

 

 

 

 

 On 21 Aug. 2026 at 9:09 UT, M1.7 class limb flare started above active region 14507. The flare peaked at 9:57 UT. Bright front of a coronal mass ejection (CME) was observed by LASCO C2 coronagraph at 9:36 UT. As the flare developed, a set of postflare loops was formed above the active region. In classical flare model, the postflare loops are formed  in the tail of rising magnetic flux tube which eventually form the CME. Cartoon published by Cheng et al (2011, DOI: 10.1088/2041-8205/732/2/L25) demonstrates this development. As the reconnection site moves higher in the corona, the postflare loops formed higher and higher. GONG stations in Canary Islands and in Chile recorded the development and evolution of postflare loops. First sign of the reconnection can be seen in GONG/TD images starting at about 10:10 UT. Attached video shows the development and evolution of postflare loops as observed by GONG/TD. Second video shows postflare loops in later phases of CME eruption as observed by GONG/CT.

 

 

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 315 covering the period 20260418 to 20260523,  and  the  p-mode frequency data products for central GONG month 314 spanning 20260313 to 20260417 is completed and the data products are now available.

GONG at CTIO is back on line

GONG at Cerro Tololo Inter-American Observatory (CTIO, Chile) is back on the Sun and observing! Below is one of the first H-alpha images taken early today (21 Aug 2026).

 

 

What goes up, goes down

On 20 August 2026, C8.0 class flare occurred in active region NOAA 14513. The active region was at about Eastern limb of the Sun. The flare was accompanied by a filament eruption, and a coronal mass ejection (CME).  Flare brightennings start appearing at about 11:24 UT.  Full flare ribbon is seen at 11:34 UT, and the first signs of erupting filament appear a minute later  at 11:35 UT.  CCOR1 observations show bright CME front appearing at about 12:00-12:15 UT. Attached video shows the filament eruption as observed by GONG at Teide (Canary Islands) station.

While most of the filament material leaved the Sun and formed the CME, some material can be seen falling down to the Sun. 

 

Some good news from CTIO

Finally we received good news from CTIO. Their TelOps day crew resumed working on Tololo regularly yesterday, although it will be next week before they have staff staying overnight. NISP team is attempting to restart the GONG operations. The skies over Tololo are beautifully blue (photo is courtesy of S. Heathcote).

 

Update on the status of the CTIO facilities

This is an update on the status of the mountain (CTIO) facilities and the prospects for reopening, which was received from the Director of the Cerro Tololo Observatory.

"Conditions are considerably better than in my last report and we are almost, but not quite, ready to resume regular operations.

After more than 20 days hard work by facilities operations  staff and contractors the access road has been repaired sufficiently to allow safe access by staff and, importantly, by heavy vehicles.  TelOps staff began recovery and planned engineering work at the Blanco telescope last Monday and teams from SOAR, Gemini and Rubin were able to get to Pachon for initial inspections last Friday.  We were also able to resupply the generators on Tololo last Friday and trucked water from a new provisional well to refill the water tanks this Monday.  You can find more information and pictures of the recovery work here 

Because a new storm front was forecast to bring rain and snow again today and continue over the weekend we again suspended work on the mountain today for safety reasons. However, so far the front has been much weaker than predicted so we may be able to resume work tomorrow.  FacOps have been able to provide hot lunches for the work crews this week and plans to resume full food and lodging services next week This will allow us to return to something more like normality with the full day crew going to the mountain each day and some staff staying overnight by the middle of next week.

So I hope that it will be possible to begin powering up and resuming operation of your telescopes on Tololo by the end of next week."

Total Solar Eclipse as observed at Ebro Observatory

On 11-12 August 2026, the IAU Working Group on Coordination of Synoptic Observations of the Sun and the International Space Weather Action Team on Data sets of historical observations of solar and geomagnetic activity (S1-03) held a joint workshop on "Synoptic ground-based solar observations for space weather and space climate". The workshop took place at the Ebro Observatory and included presentations about preservation of historical data, use of historical data for modern scientific research, current state of observational facilities in different countries, and plans for future networks of synoptic observations (ngGONG and SOLARNET/SPRING). The workshop was attended by scientists from Belgium, Czech Republic, Germany, Japan, Spain, Switzerland, and USA. On the last day, the workshop was visited by Dr.  Núria Montserrat, Minister for Research and Universities of the Catalan Government and Ellen S. Baker, a former NASA astronaut. Photo 1 shows (left to righth) Dr. Juan José Curto, Dr.  Montserrat, and Ms. Baker greeting the workshop participants. Their visit was related to the activities organized by the Observatory with respect to public viewing of the total solar eclipse.

 

The event included several public lectures about the history of Ebro Observatory, space flights from the perspective of former Spanish and US astronauts, astronomy studies of exoplanets, and space weather effects on Earth (photo 2). Before and during the eclipse, the observatory personnel was taking measurements of the atmospheric properties (wind, temperature) using small weather balloons (photo 3). Children were invited to draw pictures of solar atmosphere and stellar nebula (photo 4). 

 

Total solar eclipse took place at the end of the day during the sunset (see photos 5 and 6). After the dark, the evening concluded by public viewing of Perseids meteor shower.

 

Last image (photo 7) shows partial solar eclipse as observed by GONG at Teide station on Canary Islands. 

 

Getting ready for the eclipse?

The last total solar eclipse in Spain happened on August 30, 1905 (121 years ago!) and so, perhaps it is not surprising that the signs of this year eclipse (August 12, 2026) are everywhere. Would you like to try "Eclipse 2026" ice cream (photos 1-2)? Or perhaps, come to a roof-top at a hotel in Barcelona (photo 3). Eclipse creme brulee anyone (photo 4)? Photos 5-6 show eclipse signs for the public viewing event at the Ebro Observatory (Observatori de l’Ebre) in Tortosa, Catalonia.