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Open AccessInitiation of a lightning search using the lightning and airglow camera onboard the Venus orbiter Akatsuki
The existence of lightning discharges in the Venus atmosphere has been controversial for more than 30 years, with many positive and negative reports published. The lightning and airglow camera (LAC) onboard th...
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Open AccessVenus looks different from day to night across wavelengths: morphology from Akatsuki multispectral images
Since insertion into orbit on December 7, 2015, the Akatsuki orbiter has returned global images of Venus from its four imaging cameras at eleven discrete wavelengths from ultraviolet (283 and 365 nm) and near ...
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Article
Open AccessUltraviolet imager on Venus orbiter Akatsuki and its initial results
The ultraviolet imager (UVI) has been developed for the Akatsuki spacecraft (Venus Climate Orbiter mission). The UVI takes ultraviolet (UV) images of the solar radiation reflected by the Venusian clouds with nar...
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Open AccessInitial products of Akatsuki 1-μm camera
The status and initial products of the 1-μm camera onboard the Akatsuki mission to Venus are presented. After the successful retrial of Venus’ orbit insertion on Dec. 2015 (5 years after the failure in Dec. 20...
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Open AccessOverview of Akatsuki data products: definition of data levels, method and accuracy of geometric correction
We provide an overview of data products from observations by the Japanese Venus Climate Orbiter, Akatsuki, and describe the definition and content of each data-processing level. Levels 1 and 2 consist of non-c...
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Open AccessPerformance of Akatsuki/IR2 in Venus orbit: the first year
The first year (December 2015 to November 2016) of IR2 after Akatsuki’s successful insertion to an elongated elliptical orbit around Venus is reported with performance evaluation and results of data acquisitio...
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Open AccessAbsolute calibration of brightness temperature of the Venus disk observed by the Longwave Infrared Camera onboard Akatsuki
The Venus Climate Orbiter Akatsuki arrived at Venus in December 2015, and the Longwave Infrared Camera (LIR) onboard the spacecraft started making observations. LIR has acquired more than 8000 images during th...
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Open AccessInitial performance of the radio occultation experiment in the Venus orbiter mission Akatsuki
After the arrival of Akatsuki spacecraft of Japan Aerospace Exploration Agency at Venus in December 2015, the radio occultation experiment, termed RS (Radio Science), obtained 19 vertical profiles of the Venus...
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Open AccessFeasibility of retrieving dust properties and total column water vapor from solar spectra measured using a lander camera on Mars
Dust and water vapor are important constituents in the Martian atmosphere, exerting significant influence on the heat balance of the atmosphere and surface. We have developed a method to retrieve optical and p...
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Open AccessAn overview of VHF lightning observations by digital interferometry from ISS/JEM-GLIMS
The Global Lightning and sprIte MeasurementS (GLIMS) mission has been conducted at the Exposed Facility of Japanese Experiment Module (JEM-EF) of the International Space Station for more than 30 months. This p...
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Open AccessAKATSUKI returns to Venus
AKATSUKI is the Japanese Venus Climate Orbiter that was designed to investigate the climate system of Venus. The orbiter was launched on May 21, 2010, and it reached Venus on December 7, 2010. Thrust was appl...
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Open AccessDevelopment and in-flight calibration of IR2: 2-μm camera onboard Japan’s Venus orbiter, Akatsuki
IR2, a near-infrared camera in the 2-μm region onboard Akatsuki has been developed to primarily study the middle-to-lower atmospheric dynamics of Venus as probed in the 1.74- and 2.3-μm “windows” of the ...
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Open AccessLIR: Longwave Infrared Camera onboard the Venus orbiter Akatsuki
The Longwave Infrared Camera (LIR) is one of a suite of cameras onboard the Venus orbiter Akatsuki. It will take images of thermal radiation in the wavelength range of 8–12 µm emitted by the Venus cloud tops. ...
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Open AccessEvaluation of ozone column amount from the solar backscattering spectra measured with a spectrograph onboard an aircraft
Slant column amounts of ozone were evaluated from the solar backscattered spectra measured with a simple spectrograph onboard an aircraft over the Pacific Ocean south of Japan in January 2002. A least-squares ...