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Local K-Index


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Local K Index



The S4 Index is a standard index used to measure ionospheric disturbances. It is defined as the ratio of the standard deviation of signal intensity to the average signal intensity.




Daily Brief

Issued By Pussainsa 2020-09-29

Solar Activity / X Ray Flares

Solar activity was quiet for the last 24 hours. Neither flare, CME nor solar radio burst occurred in the last 24 hour. The latest BBSO H-Alpha data shows an H-Alpha plage. STEREO EUVI/AIA 195 observation shows no new active region is going to appear from the east limb of the Solar disk in the next 24 hours.

Based on today's condition, solar activity for the next 24 hours is predicted to be quiet.

Solar Wind / Geomagnetic Activity

The geomagnetic activity was in active level for the last 24 hours.

The solar wind speed fluctuated from 630 km/s to 555 km/s. The North-south component of the interplanetary magnetic field fluctuated from -6 to 6 nT. There was geoeffective coronal hole at north pole to northwestern equator, while no coronal hole which not geoeffective.

Active level geomagnetic is expected for the next 24 hours.

Ionosphere / Scintillation

The ionosphere was disturbed on moderate level conditions for the last 24 hours.

There was depression of foF2 lower than 30% of its median value for 315 minutes. There was increment of fmin more than 30% of its median values for 15 minutes. The Spread-F not occurred. The Sporadic-E occurred in the night and daytime for 450 minutes. The W-index mean value was 2. The S4 index values (condition of ionospheric scintillation) was less than 0.5 over Bandung.

The ionosphere activity on the next 24 hours is predicted to be moderate.

Solar Energetic Particles (Protons)

The flux of high-energy proton was quiet for the last 24 hours. 

Based on solar activity prediction, the flux of high-energy proton for the next 24 hours is predicted to be quiet.