Solar alert

Issued on 2023 Sep 13 1103 UTC

A solar wind shock was observed on September 12 at 11:22 UTC in the solar wind parameters as recorded by DSCOVR. The total interplanetary magnetic field (Bt) jumped from 11 nT to 18 nT, the solar wind speed also jumped from 361 km/s to 409 km/s. The signature of the solar wind shock was also visible in the southward component (Bz) and the solar wind density. Then, the total interplanetary magnetic field (Bt) increased up to 20 nT, the southward component (Bz) reached -19 nT, and the solar wind speed rose up to 440 km/s. This solar wind shock is associate to a relatively slow solar structure (with a maximum speed of 440 km/s). It can be associated with the arrival of the glancing of a partial halo coronal mass ejection (CME) that was observed on September 07.

Following the solar wind enhancement, a geomagnetic storm was observed (Kp=6- and K_BEL=5) on September 12 at 15:00 UTC.

Reference for this alert

All Presto solar alerts