Parker Solar Probe Imaging of the Night Side of Venus. Issue 3 (9th February 2022)

• Record Type: Journal Article
• Authors: Wood, Brian E.; Hess, Phillip; Lustig‐Yaeger, Jacob; Gallagher, Brendan; Korwan, Daniel; Rich, Nathan; Stenborg, Guillermo; Thernisien, Arnaud; Qadri, Syed N.; Santiago, Freddie; Peralta, Javier; Arney, Giada N.; Izenberg, Noam R.; Vourlidas, Angelos; Linton, Mark G.; Howard, Russell A.; Raouafi, Nour E.
• Is Part Of: Geophysical research letters. Volume 49:Issue 3(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-02-09
• Subjects: Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1029/2021GL096302
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: We present images of Venus from the Wide‐Field Imager for Parker Solar Probe (WISPR) telescope on board the Parker Solar Probe (PSP) spacecraft, obtained during PSP's third and fourth flybys of Venus on 2020 July 11 and 2021 February 20, respectively. Thermal emission from the surface is observed on the night side, representing the shortest wavelength observations of this emission ever, the first detection of the Venusian surface by an optical telescope observing below 0.8 μm. Consistent with previous observations at 1 μm, the cooler highland areas are fainter than the surrounding lowlands. The irradiances measured by WISPR are consistent with model predictions assuming a surface temperature of T = 735 K. In addition to the thermal emission, the WISPR images also show bright nightglow emission at the limb, and we compare the WISPR intensities with previous spectroscopic measurements of the molecular oxygen nightglow lines from Venus Express. Plain Language Summary: During two recent gravity‐assist flybys, the Wide‐Field Imager for Parker Solar Probe (WISPR) imager on board NASA's Parker Solar Probe observed the night side of Venus and unexpectedly penetrated its thick atmosphere, detecting thermal emission from the surface, making this the first detection of the Venusian surface by an optical telescope. The thermal emission is detectable due to the high temperature of the Venusian surface, which even on the night side reaches an estimated T = 735 K. The WISPR images also show a bright rim of emission at the limb, associated with nightglow emission from molecular oxygen, somewhat analogous to auroral emissions observed at Earth. Key Points: First results are reported about images of the night side of Venus from the WISPR imager on board Parker Solar Probe Thermal emission from the surface is observed at shorter wavelengths than ever before seen Nightglow emission from molecular oxygen is observed at the limb