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Jupiter's X-Ray and UV Dark Polar Region.

ABSTRACT: We present 14 simultaneous Chandra X-ray Observatory (CXO)-Hubble Space Telescope (HST) observations of Jupiter's Northern X-ray and ultraviolet (UV) aurorae from 2016 to 2019. Despite the variety of dynamic UV and X-ray auroral structures, one region is conspicuous by its persistent absence of emission: the dark polar region (DPR). Previous HST observations have shown that very little UV emission is produced by the DPR. We find that the DPR also produces very few X-ray photons. For all 14 observations, the low level of X-ray emission from the DPR is consistent (within 2-standard deviations) with scattered solar emission and/or photons spread by Chandra's Point Spread Function from known X-ray-bright regions. We therefore conclude that for these 14 observations the DPR produced no statistically significant detectable X-ray signature.

SUBMITTER: Dunn WR

PROVIDER: S-EPMC9287093 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Jupiter's X-Ray and UV Dark Polar Region.

Dunn W R WR Weigt D M DM Grodent D D Yao Z H ZH May D D Feigelman K K Sipos B B Fleming D D McEntee S S Bonfond B B Gladstone G R GR Johnson R E RE Jackman C M CM Guo R L RL Branduardi-Raymont G G Wibisono A D AD Kraft R P RP Nichols J D JD Ray L C LC

Geophysical research letters 20220607 11

We present 14 simultaneous Chandra X-ray Observatory (CXO)-Hubble Space Telescope (HST) observations of Jupiter's Northern X-ray and ultraviolet (UV) aurorae from 2016 to 2019. Despite the variety of dynamic UV and X-ray auroral structures, one region is conspicuous by its persistent absence of emission: the dark polar region (DPR). Previous HST observations have shown that very little UV emission is produced by the DPR. We find that the DPR also produces very few X-ray photons. For all 14 obser ...[more]

PMID: 35865009

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