Media release

From: Springer Nature

Astronomy: Gamma-ray burst detected in Earth’s upper ionosphere *IMAGE*

A very bright and long-lasting gamma-ray burst (GRB), named GRB 221009A, may have led to large variations in the ionospheric electric field in the Earth’s upper ionosphere at 500 km, reports a Nature Communications paper. The authors suggest that this GRB may be amongst the strongest ever detected in the Earth’s atmosphere.

The ionization stability of Earth’s atmosphere plays a fundamental role for the evolution and endurance of life, and is exposed to the effect of cosmic explosions producing high energy GRBs. These GRBs may cause ionospheric disturbances as released energetic particles can abnormally ionize the ionosphere. Although their impact on the lower ionosphere of the Earth is known, GRB impacts on the upper ionosphere have not been observed before. Previous research has shown that GRB221009A caused ionospheric perturbations in the lower ionosphere, but not the upper ionosphere.

Mirko Piersanti and colleagues analysed ionospheric data acquired by satellites and ground-based stations. They found evidence that on 9th October 2022, an intense and long-lasting ionospheric perturbation created a large variation of the upper ionospheric electric field, both of which correlated with GRB221009A. The GRB was around seven minutes long, but was detectable for more than ten hours following initial detection.