Solar Magnetic Activity

GONG farside

The far-side image display the seismic signature of magnetic activity on the side of the Sun that we cannot directly see from Earth. Darker regions indicate locations where there is an accumulation of magnetic field. Credits: NSO/GONG

HMI Magnetogram

HMI, from SDO, measures the Sun’s magnetic field over the entire visible disk with 1 arc second resolution. Credits: the Joint Science Operations Center (JSOC)

Solar Magnetic Cycles

This plot shows time vs. solar latitude of the radial component of the solar magnetic field, averaged over successive solar rotation. Sunspot signatures are clearly visible at low latitudes. Credits: the solar group at NASA Marshall Space Flight Center (NASA/MSFC).

PFSS Model

A plot of four categories of field lines from the Potential-Field Source-Surface Models: open positive (outward) flux, open negative flux, and the tallest closed flux trajectories in blue. Also plotted is the original synoptic magnetogram, with flux density from white (maximum-strength positive flux) to black (maximum-strength negative flux). Credits: NSO/NISP.

Coronal Response

Solar Flares

Solar flares are seen as bright regions in images observed by AIA onboard SDO.
The intense electromagnetic radiation causes low frequency and HF communication problems. Credits: SDO and SWPC

Coronal Mass Ejections

Coronal mass ejections (“CMEs”)

CMEs are seen as large plasma clouds in coronagraph images observed by LASCO onboard SOHO.
The small white circle shows the size of the solar disk. Credits: SOHO and SWPC

Coronal Holes

Coronal holes are seen as dark areas in 193 Å with AIA onboard SDO. Fast solar wind is streaming out of coronal holes. High energy electrons, as measured by GOES may cause satellite anomalies. Credits: SDO and SWPC

Solar Wind – L1

ACE data

Fast solar wind and large negative B_z values cause geomagnetic storms. Credits: NOAA/ACE

SOHO data

Celias onboard SOHO measures also solar wind at L1 and may complement ACE when plasma measurements from ACE are not reliable. Credits: CELIAS/MTOF Proton Monitor

Observations