Detailed Information

Solar Activity

Solar activity over the past 24 hours was eruptive.

A total of 10 C-class flares were observed, with no M-class or X-class flares occurring. The most significant event was a C4.4 flare peaking at 1:17UT from an UNKNOWN REGION. Associated with this activity, there were 8 Type III solar radio bursts recorded, with no Type II or Type IV radio bursts detected. Additionally, 8 coronal mass ejections were observed, with those from the east limb having a median speed of 517 kilometers per second and a median angular width of 28 degrees; no CMEs were observed from the west limb. On the visible disk, SDO/HMI instruments detected four active regions: NOAA 14419, NOAA 14420, NOAA 14421, and NOAA 14422. No H-Alpha plages were observed by BBSO. Looking to the farside, two regions are expected to emerge onto the visible disk between April 23 and April 25.

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

Geomagnetic Activity

The geomagnetic activity was on quiet level for the last 24 hours.
The solar wind speed decrease from 603 km/s to 474 km/s, north-south component of interplanetary magnetic field fluctuate between -5.3 nT and 4.6 nT. There was geoeffective coronal hole at western equator, while the others at south-east, eastern equator and north-east were not geoeffective.

Quiet level geomagnetic activity is expected for the next 24 hours.

 

Ionospheric Activity

Ionosphere was in quiet conditions for the last 24 hours.

There was depression of foF2 lower than 30% of its median value for 15 minutes. There was increment of fmin more than 30% of its median values for 150 minutes.  The Spread-F occured for 450 minutes for the last 24 hours. The Sporadic-E occurred in the night and daytime with foEs value exceeded the foF2 for several times for 960 minutes. The S4 index values (condition of ionospheric scintillation ) was over than 0.4 and the maximum TEC index value was at 76.67 both over Pontianak for the last 24 hours.

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

Navigation

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

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

HF Radio Communication

Maximum Usable Frequency (MUF) Depression was in quiet condition and the Short Wave Fadeout (SWF) was in strong for the last 24 hours.

The MUF Depression for the next is predicted to be at quiet levels based on past geomagnetic activity.

The SWF for the next 24 hours is forecasted at minor based on predicted solar flare classes.

Satellites

The electron flux was on high level for the last 24 hours.

High level of electron flux is expected for the next 24 hours.

The flux of high-energy protons in the past 24 hours was quiet.

Based on today's conditions, the flux of high-energy protons for the next 24 hours is predicted to be quiet.