March 1989 geomagnetic storm
Artist's depiction of solar wind striking Earth's magnetosphere (size and distance not to scale) | |
| Associated solar active region | |
|---|---|
| NOAA region no. | 5395 |
| Largest SXR flares | X15 |
| Geomagnetic storm | |
| Initial onset | 9 March 1989 |
| Dissipated | 13 March 1989 |
| Highest Kp-index | 9 |
| Highest Ap-index | 246 |
| Lowest Dst | −589 nT |
| Impacts | Global communications blackouts; loss of power to the Hydro-Québec power grid |
Part of solar cycle 22 | |
The March 1989 geomagnetic storm occurred as part of severe to extreme solar storms during early to mid March 1989, the most notable being a geomagnetic storm that struck Earth on March 13. This geomagnetic storm caused a nine-hour outage of Hydro-Québec's electricity transmission system. The onset time was exceptionally rapid. Other historically significant solar storms occurred later in 1989, during a very active period of solar cycle 22.