American Journal of Astronomy and Astrophysics

Volume 8, Issue 3, September 2020

  • A Critical Review of the Lunar Laser Ranging

    Andreas Märki

    Issue: Volume 8, Issue 3, September 2020
    Pages: 39-44
    Received: Jul. 14, 2020
    Accepted: Jul. 31, 2020
    Published: Aug. 20, 2020
    Abstract: This paper provides an overview of the Lunar Laser Ranging (LLR) experiments. The measurement principle is explained and its theory is derived. Both contributions, the direct reflected light from retroreflectors as well as the scattered light from the lunar surface are considered. The measurement results from the Sixties until 2007 are then compare... Show More
  • Application of New Formulas for the Spiral Arm Formation to Selected Galaxies with Special Patterns

    Hongjun Pan

    Issue: Volume 8, Issue 3, September 2020
    Pages: 45-60
    Received: Aug. 20, 2020
    Accepted: Aug. 31, 2020
    Published: Sep. 16, 2020
    Abstract: Seven special galaxies with very unusual spiral patterns are precisely simulated and studied by recently proposed ROTASE hypothesis with derived mathematical formulas for the spiral arm formation of the galaxies, fully match the prediction of the model. MCG+00-04-051 shows the broken connection of the spiral arms with the ends of the galactic bar, ... Show More
  • Formation and Change of Planetary Magnetic Field

    Cuixiang Zhong

    Issue: Volume 8, Issue 3, September 2020
    Pages: 61-65
    Received: Aug. 26, 2020
    Accepted: Sep. 14, 2020
    Published: Sep. 25, 2020
    Abstract: The influential theories about the origin of planetary magnetic field hold that the planetary magnetic field is produced by the flow of conductive fluid in the core. But these hypotheses have serious defects, unable to explain the inhomogeneity of the spatial distribution of planetary magnetic field and its changing characteristics with time. Thus,... Show More