| 1. |
- Orsini, S., et al.
(författare)
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Inner southern magnetosphere observation of Mercury via SERENA ion sensors in BepiColombo mission
- 2022
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Ingår i: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Mercury’s southern inner magnetosphere is an unexplored region as it was not observed by earlier space missions. In October 2021, BepiColombo mission has passed through this region during its first Mercury flyby. Here, we describe the observations of SERENA ion sensors nearby and inside Mercury’s magnetosphere. An intermittent high-energy signal, possibly due to an interplanetary magnetic flux rope, has been observed downstream Mercury, together with low energy solar wind. Low energy ions, possibly due to satellite outgassing, were detected outside the magnetosphere. The dayside magnetopause and bow-shock crossing were much closer to the planet than expected, signature of a highly eroded magnetosphere. Different ion populations have been observed inside the magnetosphere, like low latitude boundary layer at magnetopause inbound and partial ring current at dawn close to the planet. These observations are important for understanding the weak magnetosphere behavior so close to the Sun, revealing details never reached before.
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| 2. |
- Domingue, Deborah L., et al.
(författare)
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Whole-disk spectrophotometric properties of Mercury : Synthesis of MESSENGER and ground-based observations
- 2010
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Ingår i: Icarus. - : Elsevier BV. - 0019-1035 .- 1090-2643. ; 209:1, s. 101-124
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Tidskriftsartikel (refereegranskat)abstract
- Disk-integrated and disk-resolved measurements of Mercury's surface obtained by both the Mercury Dual Imaging System (MDIS) and the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) onboard the MErcury Surface. Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft were analyzed and compared with previous ground-based observations of Mercury at 11 wavelengths The spectra show no definitive absorption features and display a red spectral slope (increasing reflectance with increasing wavelength) typical of space-weathered rocky sui faces The MDIS spectra show evidence of phase reddening, which is not observed in the MASCS spectra The MDIS spectra are commensurate with ground-based observations to within 10%, whereas the MASCS spectra display greater discrepancies with ground-based observations at near-infrared wavelengths The derived photometric calibrations provide corrections within 10% for observations taken at phase angles less than similar to 100 degrees The derived photometric properties are indicative of a more compact regolith than that of the lunar surface or of average S-type asteroids The photometric roughness of the cur face is also much smoother than the Moon's The calculated geometric albedo (reflectance at zero phase) is higher than lunar values The lower reflectance of immature units on Mercury compared with immature units Oil the Moon, in conjunction with the higher geometric albedo, is indicative of more complicated grain structures within Mercury's regolith.
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