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A series of experiments were conducted with a conjunction between the midlatitude SURA ionospheric heating facility and the multisatellite SWARM mission. We present the first observations made by SWARM on the plasma perturbations and electric currents induced in the F2 region ionosphere by the high‐power high‐frequency O‐mode radio wave pumping. In the heated region, significant effects include a localized increase of the electron temperature accompanied by stratification of the electron density and the magnetic signatures of field‐aligned currents (FACs). The spatial structure and amplitude of FACs indicate that the current system is likely associated with the unipolar diffusion and excitation of eddy electric currents in the ionosphere. Similar effects are revealed in the laboratory experiment but not previously observed in space.

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In June 2018, for the first time, the SURA heating facility in Russia , together with the in‐orbit China Seismo‐Electromagnetic Satellite (CSES), carried out a series of experiments in emitting high frequency (HF) O‐mode radio waves to disturb the ionosphere. This paper reports data from those experiments, collected onboard CSES, including electric field, in‐situ plasma parameters, and energetic particle flux. Five cases are analyzed, two cases in local daytime and three in local nighttime. We find that the pumping wave frequencies f0 in local daytime were close to the critical frequency of the F2 layer foF2, but no pumping waves were detected by the electric field detector (EFD) on CSES even when the emitted power reached 90 MW, and no obvious plasma disturbances were observed from CSES in those two daytime cases. But on June 16, there existed a spread F phenomena when f0 was lower than foF2 at that local daytime period. During the three cases in local nighttime, the pumping waves were clearly distinguished in the HF‐band electric field at the emitted frequency with the emitted power only 30 MW; the power spectrum density of the electric field was larger by an order of magnitude than the normal background, with the propagating radius exceeding 200 km. Due to the small foF2 over SURA in June at that local nighttime period,f0 in these three cases were significantly higher than foF2, all belonging to under‐dense heating conditions. As for the plasma parameters, only an increase of about 100 K in ion temperature was observed on June 12; in the other two cases (with one orbit without plasma data on June 17), no obvious plasma disturbances were found. This first joint SURA‐CSES experiment illustrates that the present orbit of CSES can cross quite close to the SURA facility, which can insure an effective heating time from SURA so that CSES can observe the perturbations at the topside ionosphere excited by SURA in the near region. The detection of plasma disturbances on June 12 with under‐dense heating mode in local nighttime provides evidence for likely success of future related experiments between CSES and SURA, or with other HF facilities.