The first satellite which can flash Morse code on orbit is introduced in this paper. The design of the system includes light energy estimation, attitude mode design, elevation angle analysis and flash time design. It is a 100 kg satellite with two LED arrays on 547 km. When it flashes, the satellite points to the observation location. The LED rays flash as the rule of Morse code. The satellite was sent to the orbit in Dec 2018 and the test of flash was completed within one month after then. The photo taken by star sensor can compare the apparent magnitude by the gray level. The results of the analysis show that the satellite can achieve 0 apparent magnitude, which is consistent with the design of the system. As a meaningful scientific experiment, “Ladybeetle-1” links space technology with popular science education and also provides a reference for space applications.
Analyses of REEs in 25 bulk samples collected from the Longtan Formation (Late Permian) in Mount Huaying district of Sichuan Province were determined useing Inductively Coupled Plasma Mass Spectrometry. The results indicate that REEs patterns are not controlled by materials from the seawater, whereas the contribution of land plants is limited. The predominant sources of REEs are from terrigenous material as indicated by negative Eu anomaly. The Mount Emei basalt contributes to REEs enrichment of study area. So the sources of REEs are controlled by terrigenous material of Mount Emei basalt, which dominates the enrichment and pattern of REEs in Late Permian mudstone from Mount Huaying.
Rare earth elements (REEs) are good geological indicators. In order to understand REEs stratigraphic significance, REEs in Late Permian coal measure stratum from Mount Huaying, eastern Sichuan Province, China were studied. The results indicate that the contents of both light rare earth element (LREE) and REE are dramatic change in the boundary between Longtan Formation and Maokou Formation, which result from the gyration and discontinuity eruption of Emeishan basalt (REEs source and controlling factor of enrichment) and frequent transgression-regression during forming basin. The coal measure stratum could be subdivided and correlate, and the sea-level change could be under stand by studying REEs content variation in coal measure. The phenomena show that REEs, like fossils and rocks, can be used as indicators to subdivide and correlate strata. Although the other geochemical elements and geochemical methods are conducted to indicate and determine the stratigraphic boundary, only a few of reports about REEs have been published.
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