What does this data represent?

This data is provided by a pair of GOES Satellites. The lines will move up at Noon (satellite local time) and then down at Midnight (satellite local time). Any rapid deviation in the latest incoming data could indicate the possible arrival of an interplanetary shock. More information below.

Example of a sudden impulse detected by the GOES magnetometer

More information

The GOES Hp plot contains the 1-minute averaged parallel component of the magnetic field in nanoTeslas (nT), as measured at GOES-13 (W75) and GOES-15 (W89). The Hp component is perpendicular to the satellite orbit plane and Hp is essentially parallel to Earth's rotation axis. If these data drop to near zero, or less, when the satellite is on the dayside it may be due to a compression of Earth's magnetopause to within geosynchronous orbit, exposing satellites to negative and/or highly variable magnetic fields. On the nightside, a near zero, or less, value of the field indicates strong currents that are often associated with substorms and an intensification of currents in the Earth's geomagnetic tail. Noon and midnight local time at the satellite are plotted as N and M. Default scaling is 0 to 200 nanoTesla. Non-default scaling to include infrequent extreme values is lableled in red to emphasize the change in scale.