Yazhou Yang

Chinese Academy of Sciences | CAS · National Space Science Center

The oxide abundances of the lunar regolith are fundamental for understanding the geological evolution of the Moon both regionally and globally. Several models have been constructed to estimate the oxide contents of lunar regolith from the visible and near-infrared (VNIR) spectra based on Apollo and Luna samples. In recent years, China's successful...

Solar wind can directly interact with the lunar surface and bring a space weathering effect. Some solar wind protons can be scattered as energetic neutral atoms (ENAs), which include rich information of the solar wind-surface interaction. However, people still know little about the ENA truth on the lunar ground due to the lack of in situ measuremen...

Remote sensing data revealed that the presence of water (OH/H2O) on the Moon is latitude-dependent and probably time-of-day variation, suggesting a solar wind (SW)-originated water with a high degassing loss rate on the lunar surface. However, it is unknown whether or not the SW-derived water in lunar soil grains can be preserved beneath the surfac...

Most solid planetary bodies in the solar system are covered by a layer of fine particles and the topic of light scattering by small particles has been thoroughly studied in the past decades. In contrast, light reflection from intact rocks has received much less attention, though the spectral features of fresh rocks are more diagnostic than that of...

Visible and near-infrared reflectance spectroscopy is a powerful technique in remotely identifying the mineralogical and chemical compositions of planetary surface materials. Reflectance spectra measured at varied illumination and viewing conditions may also reveal the physical properties of planetary surfaces. The accurate data interpretation woul...

Chang'E-5 (CE-5) landed in the northeast of the Oceanus Procellarum and successfully returned ∼1.73 kg lunar samples from a distinctively young mare basalt unit. The reflectance spectra between 0.45 μm to 3.20 μm at the landing site were acquired by the onboard Lunar Mineralogical Spectrometer before and after the sampling. The results from the spe...

The Chang’e‐5 (CE‐5) mission has successfully returned samples from a site that is much younger than the sites of all previous lunar sampling missions. Sample analysis results reported so far have revealed a more complex sampling area than previously thought, casting uncertainties over the interpretation of remote sensing spectral data and the U an...

The photometric properties of the uppermost lunar regolith are used in the spectroscopic study. China's Chang’E‐5 (CE‐5) mission successfully landed in the Northern Oceanus Procellarum of the Moon, carrying the scientific payload lunar mineralogical spectrometer (LMS). LMS performed full‐view scanning and obtained the reflectance spectra in various...

we describe a non-motorized spectro- goniometric system capable of measuring the bi-directional reflectance of particulate surfaces in the upper hemisphere in the wavelength range from 350 to 2150 nm. The incident and the viewing zenith angles can be varied from 0○ to 55○ and from 0○ to 70○, respectively. The relative viewing azimuth angle can be v...

The Moon has experienced an intense bombardment history since its formation1. Fragments of the impactor can remain on the lunar surface2–4 and can provide evidence of the evolution of the impactor composition and impact population in the Earth–Moon system3–5. However, the retained impactor fragments previously identified in the Apollo samples have...

The Visible and Near-infrared Imaging Spectrometer (VNIS) is one of the scientific payloads onboard the Yutu-2 lunar rover of the Chang’E-4 mission. Based on Acousto-Optic Tunable Filter (AOTF) dispersion, a moving platform and a calibration unit, the VNIS was designed for lunar surface observations of the far side of the Moon for composition explo...

Plain Language Summary Measuring the size and number of surface impact craters is the primary technique for dating lunar and planetary surfaces remotely. This technique relies on calibration points provided by sample return missions. The Earth's Moon is the only extraterrestrial body for which samples have been collected from multiple locations, en...

Accurate assessments of surface temperatures on the Moon are important for understanding the physical properties of the lunar surface regolith and thermal effects on the reflectance spectra beyond 2 μm. The local time resolved spectral measurements of the same region were used to estimate the surface temperature at the Chang'E-4 landing site. The r...

Context. The colour-ratio technique has been widely used in mapping planetary surfaces, but its solar phase-angle dependence is not well understood. Understanding the phase-angle dependence of the colour ratio would enhance our abilities in interpreting planetary remote sensing data. Aims. We aim to investigate the dependence of the colour ratio in...

Large shield-building volcanic structures (>30 km) with central vents are rare on the Moon. The most popular candidate targets of lunar large shield volcanoes are volcanic complexes on the lunar nearside within the compositionally evolved Procellarum KREEP terrane (PKT). However, there is a unique mass concentrated volcanic complex not within the P...

The Chang'E-4 spacecraft successfully landed in Von Kármán crater inside the South Pole-Aitken basin on the lunar far side on January 3, 2019 and the Yutu-2 Rover has performed explorations on the lunar surface for nine lunar days as of September 2019. Our earlier analysis of the visible and near-infrared spectrometer measurements made by the Yutu-...

The Chang'E-4 (CE-4) spacecraft landed successfully on the far side of the Moon on 3 January 2019, and the rover Yutu-2 has explored the lunar surface since then. The visible and near-infrared imaging spectrometer (VNIS) onboard the rover has acquired numerous spectra, providing unprecedented insight into the composition of the lunar surface. Howev...

Context. The surface composition of the Moon has mainly determined based on the visible and near-infrared spectra achieved from orbits and/or landing sites, and the spectroscopic analysis is based on photometric properties of the topmost lunar regolith. However, the lack of a ground truth for the photometric parameters of the undisturbed lunar surf...

Plain Language Summary Olivine, pyroxenes and plagioclase, the major constituent minerals of the surface of the Moon, have diagnostic absorption features in their visible and near‐infrared reflectance spectra. These features, including the wavelength position of the absorption band center and the depth of the absorption band, can be used to identif...

The vacuum and thermal environment of airless planetary surfaces, particularly those dominated by a particulate regolith such as the Moon and asteroids, produces intense near-surface thermal gradients that can substantially alter their thermal emissivity spectra when compared with spectra collected at ambient terrestrial conditions. Therefore, spec...

During its first two lunar day measurements, the visible and near‐infrared spectrometer on board the Yutu‐2 Rover of the Chang'E‐4 mission acquired six in situ reflectance spectra from the floor of Von Kármán crater within the South Pole‐Aitken basin. A spectral lookup table search has shown that the regolith at the landing site contains 56–72% pla...

Space weathering (SW) processes including solar wind irradiation and micrometeorite bombardment produce nano-phase iron (npFe) and amorphous layers that redden and darken the visible and near-infrared (VNIR) reflectance spectra of the surface of airless bodies. To understand how SW may affect the directional reflectance and polarization properties...

Laboratory spectrophotometric measurements of minerals common on the lunar surface (olivine, pyroxene, plagioclase, and ilmenite) are measured over a wavelength range of 0.4 to 2.5 μm to better understand the effects of the particle phase function (PF; P[g]) on the application of Hapke's radiative transfer model to reflectance spectra of lunar mate...

From geologic perspective, understanding the types, abundance, and size distributions of minerals allows us to address what geologic processes have been active on the lunar and planetary surface. The imaging spectrometer which was carried by the Yutu Rover of Chinese Chang’E-3 mission collected the reflectance at four different sites at the height...

Context. Visible and near-infrared spectra of asteroids are known to be susceptible to nanophase irons produced by space weathering processes, thus making mineral identifications difficult. Mid-infrared spectroscopy may retain more mineral features owing to its lattice vibrational nature. Aims. We investigate the structure and reflectance spectral...

The panorama cameras onboard the Yutu Rover of the Chang'E-3 lunar mission acquired hundreds of high-resolution color images of the lunar surface and captured the first in-situ lunar opposition effect (OE) since the Apollo era. We extracted the phase curve and the color ratio in three bands with the phase angle range from 2° to 141°. Photometric in...

The visible and near-infrared imaging spectrometer on board the Yutu Rover of Chinese Chang'E-3 mission measured the lunar surface reflectance at a close distance (~1 m) and collected four spectra at four different sites. These in situ lunar spectra have revealed less mature features than that measured remotely by spaceborne sensors such as the Moo...

We extracted in situ lunar phase curves from images taken by the panorama cameras onboard the Yutu Rover and performed photometric analysis.

The Chang’E 3 mission successfully landed on the Mare Imbrium region on December 14, 2013 and deployed the Yutu Rover to roam near the Chang’E A Crater. Although the rover roamed just over 100 meters before its premature failure, its onboard visible and near-infrared (VisNIR) imaging spectrometer was able to collect 4 spectra at 4 different sites w...

Acquiring accurate visible and near-infrared (VisNIR) reflectance values of atmosphereless celestial bodies is very important in inferring the physical and geological properties of their surficial materials. When a calibration target with inherent non-trivial absorption features is used, the calibrated reflectance would essentially always contain s...

We describe a laboratory goniometric system capable of measuring the polarized reflectance of particulate layers.