GV Leo is a W Ursa eclipsing binary with an orbital period of 0.266727 day. From the previous investigation of its light curve, it was found that this binary system has a continuous orbital period change. A light curve of GV Leo was analyzed using program MaxIm DL3 and its period change was also calculated. The results revealed that the orbital period of GV Leo was continuously decreased at...
The planets in the solar system have different characteristics in their atmospheric composition. The atmospheric composition of a planet can tell us the evolution and activities that occur on the planet. In general, to identify planetary atmospheric composition is not common, expensive and utilizes advanced instruments. In this research, we proposed a simple and affordable technique to analyze...
Siliceous sinter from several terrestrial hot springs have been identified as analogues to nearly pure opaline silica deposits, which were discovered at Columbia Hills, Mars by the rover ‘Spirit’. On Earth, mineralized microbes and silica conjointly accumulate and build up over time to produce microstromatolites, analogue to predominant structures in early Earth paleoenvironments. Here we...
The Thai lunar calendar was made from the phase of moon to defined Buddhist days and Thai traditions. The waning moon is caused by a mutual orbit of the earth, the sun and the moon. Lunar phase is ratio of bright area to the total area. The different phase each day makes a cause in the lunar calendar. The moon’s synodic period is 29.53059 days but number of days in each month must be integer....
Cosmic rays are high energy particles from space that we can measure by ground-based detectors, including neutron monitors. The leader fraction represents the fraction of the neutron count rate that is not associated with a previous neutron count in the same tube from the same nuclear interaction. The leader fraction includes new and exciting information about the cosmic ray energy...
The study about synodic period of the Moon during 1983 – 2030 by Ephemeris. The Moon’s transit time at observer’s meridian were estimated consequently and can be plotted with Julian date to compare with The transit times of the sun in the same graph, therefore the difference between two intersected points were estimated to each Synodic period of the Moon. The result was shown that there were...
We present initial condition galaxy model of NGC 5252, which galaxy has black hole, gas particles, dark matter halo particles and bulge particles. This model uses Navarro–Frenk–White (NFW) profile and Sersic profile for describes distribution of particles. NFW profile describes profile of dark matter. In another way, Sersic profile describes how the surface brightness of a system varies with...
Magnetic field line random walk (FLRW) are a resultant from the turbulence of particle and internal magnetic field lines in the interplanetary medium. When high energy particles passing through the medium, their trajectories will be bended following a magnetic FLRW behavior according to the 2D and slab model. The isotropic turbulence simulation which depends on the stretched parameter...
Cosmic rays (CRs) are high energy particles in space, mainly protons, for which the spectrum is well described by a power law. Recent measurements from PAMELA and AMS-02 indicate an abrupt change of the CR proton spectral index at $\sim$300 GeV. When CRs interact with the Earth's upper atmosphere, gamma-ray ($\gamma$-ray) photons can be produced and detected by space-based detectors. We use...
In this study of the physical properties of large stars, information from all five (5) stars were capture by shooting with a DSLR and through the Star Analyser SA-100 grating spectrometer. The observations were performed with a small 152 mm refracting telescope at the rooftop of Building 23, Faculty of Science, Lampang Rajabhat University. The data were then analyzed using the RSpec program in...
Earth auroral phases, growth, expansion, and recovery phases, are the signatures of Earth’s substorm event in the polar regions. Auroral emissions in Earth’s northern hemisphere were observed in November 6, 1998, by the Visible Imaging System (VIS) the Ultraviolet Imager (UVI), instruments onboard POLAR spacecraft. Auroral morphology during 8:00UT – 9:00UT was studied based on images taken by...
The short-period Hot Jupiter such as HD209458b has been speculated that the expansion of its atmosphere due to intense irradiation from its host star with close orbital distance might exist. Several observational evidences have shown that the planetary radius is relatively larger in shorter wavelengths with respect to optical wavelength by transit observation. It may imply that the planetary...
In this research, we aim to study an AM Her-type cataclysmic variable (CV) system, V2301 Oph. This eclipsing system has an orbital period of 1.8hrs and it is known to have a white dwarf with the weakest magnetic field ever detected in AM Her systems. The observations of V2301 Oph were obtained with the 2.4-meter reflecting telescope with an alt-azimuth drive system at the Thai National...
Abstract. This research compiles and analyses information of solar flares data and variation of the actual space environment data from spacecraft for studying the concordances of the variation solar cycle. These information are the specifically solar flare events of X and M class in 23$^{rd}$ and 24$^{th}$ solar cycles. The number of X class flares of 23$^{rd}$ solar cycle more than...
The magnetosphere of Jupiter could be partly controlled by energetic particles originated from volcanic eruption on Io. These energetic particles could affect the variation of plasma sheet’s density, and accordingly the azimuthal current inside magnetosphere. The variation of azimuthal current results in the stretching of magnetic field line of Jupiter. Accordingly, the mapping of Jupiter’s...
Galaxy clusters are the most massive gravitationally bound systems in the universe. Direct observations and theoretical studies of galaxy clusters reveal important information of large-scale structures. In this study, we use the weak gravitational lensing’s analytical technique to investigate the mass distribution in galaxy clusters. We report our preliminary results on the analysis of the...
