Solar and Aurora Activity Chat

[karyo]

After a lot of activity we have a spotless day

[JeffC]

Observed Flux Density 73.2

Adjusted Flux Density  74.0 = low

[Katrine Basso]

Daily Sun: Friday 17th September 2021

Sunspot number: 0    Updated 17 Sep 2021

Spotless Days
Current Stretch: 2 days
2021 total: 58 days (22%)

Thermosphere Climate Index
today: 5.52x1010 W Cold
Max: 49.4x1010 W Hot (10/1957)
Min: 2.05x1010 W Cold (02/2009) Updated 16 Sep 2021

The Radio Sun
10.7 cm flux: 75 sfu Updated Friday 17th September 2021

Oulu Neutron Counts
Percentages of the Space Age average:
today: +9.8% High
48-hr change: +0.4%
Max: +11.7% Very High (12/2009)
Min: -32.1% Very Low (06/1991) Updated Friday 17th September 2021 @ 0700 UT

 

[kar999]

Red alert issued...

UK Sightings on Twitter.

https://twitter.com/frenchscotjeff/status/1438985359086473216?s=19

 

 

[Katrine Basso]

THE AFTERGLOW OF A 'WEAK' CME: A CME hit Earth's magnetic field on Sept. 17th at ~0200 UT. The impact was very weak, lifting the solar wind speed by a measly 40 km/s. Despite such a feeble blow, the CME managed to stir geomagnetic activity hours later when Earth encountered magnetic fields in the CME's wake. Marketa Murray sends this picture from Fairbanks, Alaska:

[Katrine Basso]

Daily Sun: Saturday 18th September 2021

Sunspot number: 0    Updated 18 Sep 2021

Spotless Days
Current Stretch: 3 days
2021 total: 59 days (23%)

Thermosphere Climate Index
today: 5.52x1010 W Cold
Max: 49.4x1010 W Hot (10/1957)
Min: 2.05x1010 W Cold (02/2009) Updated Friday 17th September 2021

The Radio Sun
10.7 cm flux: 75 sfu Updated Saturday 18th September 2021

[Stu_London]

surprised we are still getting little phases of spotless days at this stage.

either we are not as far into the cycle as perhaps some think or we are in for a patchy cycle with periods of high activity interspersed with quieter than normal periods. Probably makes for a weakish cycle overall. Whether it is stronger than SC24 still looks a little in the balance. Whether some sort of grand minimum is underway wont become clearer until SC26.

[JeffC]

Observed Flux Density 73.7

Adjusted Flux Density 74.4 = low

[JeffC]

Observed Flux Density 75.0

Adjusted Flux Density 75.7= low

[JeffC]

Observed Flux Density 78.4

Adjusted Flux Density 79.1 = low

[JeffC]

Observed Flux Density 84.1

Adjusted Flux Density 84.8 = low

[JeffC]

Observed Flux Density 87.2

Adjusted Flux Density 87.9 = low

[Katrine Basso]

SOLAR SECTOR BOUNDARY CROSSING: Yesterday, Earth passed through a fold in the heliospheric current sheet--a vast wavy structure in interplanetary space separating regions of opposite magnetic polarity. Researchers call this a "solar sector boundary crossing" (SSBC), and here is what it did.

"Wave after wave of bright green auroras danced over the Salt River in Wood Buffalo National Park," says photographer John David McKinnon of Alberta, Canada. "The show peaked around ~08:20 UTC on Sept. 22nd."

The display was also photographed from hot tubs in Iceland and moonlit landscapes in Scandinavia. This sets the stage for a possible CME impact on Sept. 23th, which could add its effect to that of the SSBC, sparking even brighter auroras around the Arctic Circle.

[JeffC]

Observed Flux Density 89.7

Adjusted Flux Density 90.2 = low

[JeffC]

Observed Flux Density 87.1

Adjusted Flux Density 87.7 = low

[JeffC]

Observed Flux Density 87.7

Adjusted Flux Density 88.2 = low

[JeffC]

Observed Flux Density 87.4

Adjusted Flux Density 87.8 = low

[Katrine Basso]

AURORAS BEFORE THE STORM: The storm hasn't started yet, but auroras are already dancing over Iceland. Last night, a minor geomagnetic disturbance rippled over the island nation where Christopher Mathews was waiting with his camera.

Lights Over Lapland has a full catalogue of exciting adventures in Abisko National Park, Sweden! Check out our daytime and evening activities and book your adventure!

 

UPDATED GEOMAGNETIC STORM FORECAST: NOAA forecasters say there is a 45% chance of G1 to G2-class geomagnetic storms today, Sept. 27th, in response to a passing CME. If a storm materializes, bright auroras can be expected around the Arctic Circle with a chance for sightings in northern-tier US states. Aurora alerts: SMS Text.

AURORAS BEFORE THE STORM: The storm hasn't started yet, but auroras are already dancing over Iceland. Last night, a minor geomagnetic disturbance rippled over the island nation where Christopher Mathews was waiting with his camera:

"I shot this image of the aurora over my house in southern Iceland at about 11 pm," says Mathews. "This is a 2.5 second exposure taken at ISO 2000, with an aperture of f/2.0. "

[JeffC]

Observed Flux Density 85.0

Adjusted Flux Density 85.3 = low

[JeffC]

Observed Flux Density 86.4

Adjusted Flux Density 86.8 = low

[JeffC]

Observed Flux Density 98.2

Adjusted Flux Density 98.6 = low

[JeffC]

Observed Flux Density 94.9

Adjusted Flux Density 95.2 = low

[Weather-history]

 

[JeffC]

Observed Flux Density 94.1

Adjusted Flux Density 94.3 = low

[JeffC]

Observed Flux Density 91.6

Adjusted Flux Density 91.8 = low