4th X-class flare: X8.2 erupts from Region 2673, second strongest of the cycle

By The Watchers

A major solar flare measuring X8.2 at its peak time erupted from Active Region 2673 at 16:06 UTC on September 10, 2017. The event started at 16:44, peaked at 16:06 and ended at 16:31 UTC. This is the 4th X-class solar flare from this region since September 6 and the second strongest of the current solar cycle (Solar Cycle 24).

A Type II (estimated velocity 928 km/s) and IV radio emissions were associated with this event, suggesting a strong Coronal Mass Ejection (CME) was produced. However, due to this region’s location on the Sun’s west limb, Earth-directed CME is not likely.

The event was also associated with a 10cm Radio Burst lasting 76 minutes with peak flux of 1900 sfu. A 10cm radio burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.

Additionally, as usual with west limb eruptions, proton particles immediately spiked.

X8.2 solar flare September 10, 2017

X8.2 solar flare September 10, 2017

X8.2 solar flare September 10, 2017

X8.2 solar flare September 10, 2017

Today’s X8.2 is the 4th X-class (the strongest level) solar flare from Region 2673 since September 6 and the second strongest solar flare of Solar Cycle 24. It comes just 4 days after X9.3, the strongest solar flare of the cycle.

Solar Cycle 24 has so far had 48 X-class flares, including today’s X8.2.

Region 2673 maintains its ‘beta-gamma-delta’ magnetic configuration and is capable of producing more strong to major eruptions on the Sun. However, it is now starting its farside rotation and will no longer pose a threat to our planet. We’ll see what’s left of it in about 14 days when it comes back into Earth-view.

Sunspots on September 10, 2017

The analysis of today’s X8.2 solar flare is still in progress. The report is being updated.

SWPC alerts, watches and warnings

Space Weather Message Code: SUM10R
Serial Number: 704
Issue Time: 2017 Sep 10 1722 UTC

SUMMARY: 10cm Radio Burst
Begin Time: 2017 Sep 10 1550 UTC
Maximum Time: 2017 Sep 10 1554 UTC
End Time: 2017 Sep 10 1706 UTC
Duration: 76 minutes
Peak Flux: 1900 sfu
Latest Penticton Noon Flux: 107 sfu

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Description: A 10cm radio burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.

***

Space Weather Message Code: WARPX1
Serial Number: 470
Issue Time: 2017 Sep 10 1720 UTC

EXTENDED WARNING: Proton 10MeV Integral Flux above 10pfu expected
Extension to Serial Number: 469
Valid From: 2017 Sep 10 1630 UTC
Now Valid Until: 2017 Sep 11 2359 UTC
Warning Condition: Persistence
Predicted NOAA Scale: S3 – Strong

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Radiation – Passengers and crew in high latitude, high altitude flights may experience small, increased radiation exposures.
Spacecraft – Infrequent single-event upsets to satellites are possible.
Radio – Small effects on polar HF (high frequency) propagation resulting in fades at lower frequencies.

***

Space Weather Message Code: ALTPX2
Serial Number: 61
Issue Time: 2017 Sep 10 1711 UTC

ALERT: Proton Event 10MeV Integral Flux exceeded 100pfu
Begin Time: 2017 Sep 10 1705 UTC
NOAA Scale: S2 – Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Radiation – Passengers and crew in high latitude, high altitude flights may experience small, increased radiation exposures.
Spacecraft – Infrequent single-event upsets to satellites are possible.
Radio – Small effects on polar HF (high frequency) propagation resulting in fades at lower frequencies.

***

Space Weather Message Code: ALTPX1
Serial Number: 317
Issue Time: 2017 Sep 10 1701 UTC

ALERT: Proton Event 10MeV Integral Flux exceeded 10pfu
Begin Time: 2017 Sep 10 1645 UTC
NOAA Scale: S1 – Minor

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Radio – Minor impacts on polar HF (high frequency) radio propagation resulting in fades at lower frequencies.

***

Space Weather Message Code: ALTTP4
Serial Number: 544
Issue Time: 2017 Sep 10 1647 UTC

ALERT: Type IV Radio Emission
Begin Time: 2017 Sep 10 1608 UTC

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Description: Type IV emissions occur in association with major eruptions on the sun and are typically associated with strong coronal mass ejections and solar radiation storms.

***

Space Weather Message Code: ALTTP2
Serial Number: 1062
Issue Time: 2017 Sep 10 1647 UTC

ALERT: Type II Radio Emission
Begin Time: 2017 Sep 10 1608 UTC
Estimated Velocity: 928 km/s

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Description: Type II emissions occur in association with eruptions on the sun and typically indicate a coronal mass ejection is associated with a flare event.

***

Space Weather Message Code: ALTPC0
Serial Number: 44
Issue Time: 2017 Sep 10 1640 UTC

ALERT: Proton Event 100MeV Integral Flux exceeded 1pfu
Begin Time: 2017 Sep 10 1625 UTC

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: An enhancement in the energetic portion of the solar radiation spectrum may indicate increased biological risk to astronauts or passengers and crew in high latitude, high altitude flights. Additionally, energetic particles may represent an increased risk to all satellite systems susceptible to single event effects. This information should be used in conjunction with the current Solar Radiation Storm conditions when assessing overall impact.

***

Space Weather Message Code: WARPX1
Serial Number: 469
Issue Time: 2017 Sep 10 1632 UTC

WARNING: Proton 10MeV Integral Flux above 10pfu expected
Valid From: 2017 Sep 10 1630 UTC
Valid To: 2017 Sep 10 2359 UTC
Warning Condition: Onset
Predicted NOAA Scale: S2 – Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Radiation – Passengers and crew in high latitude, high altitude flights may experience small, increased radiation exposures.
Spacecraft – Infrequent single-event upsets to satellites are possible.
Radio – Small effects on polar HF (high frequency) propagation resulting in fades at lower frequencies.

***

Space Weather Message Code: WARPC0
Serial Number: 82
Issue Time: 2017 Sep 10 1632 UTC

WARNING: Proton 100MeV Integral Flux above 1pfu expected
Valid From: 2017 Sep 10 1630 UTC
Valid To: 2017 Sep 10 2359 UTC
Warning Condition: Onset

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: An enhancement in the energetic portion of the solar radiation spectrum may indicate increased biological risk to astronauts or passengers and crew in high latitude, high altitude flights. Additionally, energetic particles may represent an increased risk to all satellite systems susceptible to single event effects. This information should be used in conjunction with the current Solar Radiation Storm conditions when assessing overall impact.

***

Space Weather Message Code: ALTXMF
Serial Number: 273
Issue Time: 2017 Sep 10 1558 UTC

ALERT: X-Ray Flux exceeded M5
Threshold Reached: 2017 Sep 10 1553 UTC
NOAA Scale: R2 – Moderate

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/noaa-scales-explanation

Potential Impacts: Area of impact centered on sub-solar point on the sunlit side of Earth. Extent of blackout of HF (high frequency) radio communication dependent upon current X-ray Flux intensity. For real-time information on affected area and expected duration please see http://www.swpc.noaa.gov/products/d-region-absorption-predictions-d-rap.

Featured image: X8.2 solar flare erupts from Region 2673. Credit: NASA/SDO AIA 131. Acquired: 16:28 UTC

This article (4th X-class flare: X8.2 erupts from Region 2673, second strongest of the cycle) was originally published on The Watchers and syndicated by The Event Chronicle

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