Detailed Information

Solar Activity

The past 24 hours observed eruptive solar activity. A total of four C-class solar flares occurred, with no M-class or X-class flares observed. The most significant event was a C1.7 flare, peaking at 23:45 UT from NOAA 14498. Associated with this activity, two Type III solar radio bursts were detected, with no Type II or Type IV radio bursts observed. There were no coronal mass ejections observed during this period.

On the visible disk, seven active regions were identified by SDO/HMI: NOAA 14492, NOAA 14494, NOAA 14495, NOAA 14496, NOAA 14497, NOAA 14498, and NOAA 14499. There were no BBSO H-Alpha plages present. Looking ahead, two farside regions are expected to return to the visible disk between 29 July and 31 July. The solar activity for the next 24 hours is predicted to be eruptive.

Geomagnetic Activity

The geomagnetic activity was at a quiet level for the last 24 hours.
The solar wind speed was stable at around 376 km/s; the north-south component of the interplanetary magnetic field fluctuated between -6.4 nT and 5.7 nT. Coronal holes at south-east and north-east were not geoeffective.
Quiet level geomagnetic activity is expected for the next 24 hours.

 

 

 

 

Ionospheric Activity

The ionosphere was at a quiet level for the last 24 hours.

There was no depression of foF2 lower than 30% of its median value. There was no increment of fmin more than 30% of its median value. The Spread-F was not detected for the last 24 hours. There were 17 hours when Sporadic-E occurred in the night and daytime with foEs values exceeding foF2 several times. The S4 index values (condition of ionospheric scintillation ) were less than 0.5, and the maximum TEC index value was 68.97, both over Pontianak.

The ionosphere activity for the next 24 hours is predicted to be quiet.

Navigation

The error of the single-frequency GPS positioning for the last 24 hours was at a normal level, based on ionospheric scintillation and TEC variation.

Based on ionospheric scintillation and TEC variation, the probability of positioning error for the next 24 hours is predicted at a normal level.

HF Radio Communication

MUF depression was at a quiet level, and Short Wave Fadeout (SWF) was at a quiet level for the last 24 hours.

The MUF depression for the next 24 hours is predicted at a quiet level, due to the previous geomagnetic activity.

The SWF for the next 24 hours is predicted at a quiet level due to the prediction of a solar flare.

Satellites

The electron flux has been at a low level for the last 24 hours.
A low level of electron flux is expected for the next 24 hours.

The 10 MeV proton flux remained quiet over the past 24 hours. These quiet conditions are expected to persist for the next 24 hours.