We consider the physical characteristics and dynamics of the gaseous envelopes of hot Jupiters (HJs)—gas giants with a mass comparable to Jupiter's and an orbital semiaxis of less than 0.1 a.u. Although HJs were discovered almost a quarter of a century ago, many issues about their origin remain open. There are two reasons for the scientific interest in HJs. The first is the absence of such planets in the Solar System, which is challenging in all cosmogonical theories. The second is that the exoplanet atmospheres' characteristics can now be derived primarily for transit HJs by examining their absorption spectra. Thanks to their large size, such planets can be readily observed, as opposed to others, and their transits can be observed at much higher orbital inclinations. Comparatively recently, in at least some HJs, extended gas envelopes far exceeding their Roche lobes have been found. The paper focuses on the results of theoretical investigations and numerical modeling of the dynamics of HJ envelopes. We also discuss experimental testing of the obtained results and predictions using the planned Russian Spectrum-UV (international name: WSO-UV) and Millimetron space telescopes.

Correspondence should be addressed to Keywords: hot Jupiters, exoplanetary atmospheres, aeronomic models, MHD PACS: 96.15.Hy DOI: 10.3367/UFNe.2020.11.038879 URL: https://ufn.ru/en/articles/2021/8/a/ 000711503200001 2-s2.0-85119125072 2021PhyU...64..747B Citation: Bisikalo D V, Shematovich V I, Kaygorodov P V, Zhilkin A G "Gas envelopes of exoplanets—hot Jupiters" Phys. Usp. 64 747–800 (2021) BibTexBibNote ® (generic)BibNote ® (RIS)MedlineRefWorks Received: 1st, June 2020, revised: 9th, November 2020, accepted: 20th, November 2020 Оригинал: Бисикало Д В, Шематович В И, Кайгородов П В, Жилкин А Г «Газовые оболочки экзопланет—горячих юпитеров» УФН 191 785–845 (2021); DOI: 10.3367/UFNr.2020.11.038879