Space weather risk

Space weather risk refers to the exposure of satellites and orbital infrastructure to disturbances in solar activity: solar flares, coronal mass ejections and the geomagnetic storms they trigger. Unlike collision or mechanical failure risk, this peril acts without any direct physical impact: a geomagnetic storm heats and expands the upper atmosphere, increasing the atmospheric drag experienced by low-orbit satellites, which can cause them to lose altitude or reenter prematurely before reaching their operational orbit. Solar activity can also directly damage onboard electronics through induced voltage surges, disrupt communications and navigation, or distort attitude-sensor readings. The risk is especially acute for satellites still in their deployment phase, at low altitude and without enough propulsion to compensate for the added drag. For space insurers, this peril raises a specific modeling challenge: severity tracks the solar cycle, which is hard to forecast over the span of an annual policy, and a single event can simultaneously affect an entire batch of newly deployed satellites, creating an accumulation risk tied to space weather rather than to a manufacturing failure.

In February 2022, a moderate geomagnetic storm increased the atmospheric drag on 49 newly launched Starlink satellites, causing nearly 40 of them to be lost within days, at a cost SpaceX estimated at roughly $50 million.

space weather, tempête géomagnétique, geomagnetic storm risk, météo spatiale