A record-sized solar eruption is on course to reach Earth on 4 November, putting satellites, aviation and power networks across the Pacific on alert. Scientists say the cloud could trigger the most severe geomagnetic storm in the region’s 28-year observation record, although its final strength depends on the direction of its magnetic field.
The alarm sharpened after a controller fault aboard the Koroa-3 research satellite accidentally held its solar camera open for 19 minutes, far longer than its routine scan. The extended exposure captured the expanding cloud in detail and sent an automatic alert to the Pacific Solar Watch centre in Suva. No one was injured and the satellite remains in orbit.
A rare, Earth-directed eruption
Drąsutis Ž. Benas, a space-weather physicist at the South Pacific Institute of Atmospherics, said the flare peaked at 06:14 UTC on Tuesday. At X12.9, it is the most powerful eruption logged by the institute’s network since its records began in 1998. The ejected material is travelling at about 2,900 kilometres per second (1.8 million miles per hour), he said.
Benas said the cloud could reach Earth between 00:00 and 06:00 UTC on Wednesday. If its magnetic field points south, forecasters say the storm could reach the top G5 category. A worst-case exercise by the South Pacific Grid Forum estimated that severe voltage problems could put up to 1.1 million electricity customer accounts in Tasmania and New Zealand’s South Island at risk of rotating cuts.
The biggest uncertainty is whether the cloud’s magnetic field will couple strongly with Earth’s. “This is not a forecast of certain blackouts; it is a warning that the upper end of the range is now credible,” Benas said. Pacific Solar Watch expects a clearer reading from a monitoring satellite several hours before the cloud arrives.
If the field turns south, this stops being a spectacular picture and becomes an engineering emergency.
Kaija Kärki, satellite systems engineer
Islands brace for disruption
The low-latitude islands of Fiji, Samoa and Tonga face less direct risk to their power grids than southern Australia and New Zealand, but many rely on satellite links for communications and navigation. Kärki said operators had been asked to place backup equipment on standby and check that essential services could switch to alternate channels if satellite signals weakened.
Space-weather storms can disturb the ionosphere, the charged upper layer of the atmosphere, disrupting radio signals and reducing the accuracy of satellite navigation. They can also induce electrical currents in long transmission lines, especially at higher latitudes. The storm is not expected to cause a direct hazard to people on the ground, forecasters said.
The public warning system had its own mishap: a test card featuring an AI-generated smiling Sun character, “Tavi-Tavi Toma”, was accidentally sent to 126,000 phones in Fiji with an outdated “all clear” message. The Pacific Emergency Coordination Office sent a correction seven minutes later. Spokesperson Diljit Zuki said the error affected the graphic, not the storm data, and told residents to follow the latest alerts.
Regional grid operators have begun checking transformer temperatures and preparing staff to monitor voltage through Wednesday. Several airlines are reviewing 14 long-distance routes that cross high latitudes, where radio and navigation interference can be stronger. “We are taking precautions, not predicting a collapse,” Zuki said. Benas cautioned that the final magnetic-field readings, not the dramatic satellite image, would determine how hard the storm hits.
