![]() ![]() This led to the development of the Big Bang model, which predicted that the universe started in a hot, dense singularity around 13.8 billion years ago, and has since been expanding. In 1929, Edwin Hubble observed the emission spectrum of distant galaxies, and concluded a linear relationship between the distance of the galaxies and their recessional velocitiesThe only plausible explanation of this discovery is that the fabric of space itself is expanding. ![]() Due to the invariant property of the spectral line series in distant astronomical objects, they can be identified, and their observed wavelengths provide us with information about distant astronomical objects. The pattern of spectral lines of a certain element is called a spectral line series for instance, the spectral lines in the visible light range of hydrogen are called the Balmer series. Thus, the spectrum of a chemical element has a fixed pattern, with spectral lines at fixed wavelengths. Because of that, lights are only emitted at specific frequencies. Inside an atom, only certain electron energy levels are allowed. Introduction Emission spectrum and spectral line series?Įmission spectrums are maps of frequencies of electromagnetic radiation emitted by certain elements, caused by excited electrons jumping from higher energy levels to lower energy levels. Unlike the value of the Hubble parameter determined theoretically by the Planck Satellite teamthe values in this paper are determined locally. The analysis also suggests an acceleration in the expansion of the universe however, the uncertainties for the data are too big to determine a specific model for the future evolution of the universe. The data is partially primary and partially collected from online astronomical databases statistical analysis of the data of the astronomical objects plays an important role in obtaining the numerical value of the Hubble parameter. The expansion rate of the universe is then determined locally using the distances and recessional velocities of two types of ‘standard candles’, which are objects with known absolute brightness: Type Ia Supernovae and Cepheid variables. In this project, the redshifts of distant astronomical objects are calculated through emission spectrum analysis of galaxies, from which their recessional velocities are deduced. What is the current speed of expansion? Is our universe expanding at an accelerating or decelerating rate? What does this tell us about the substances in the universe and our ultimate fate? Ever since the proposal of the Big Bang model, scientists have been puzzling over the expansion rate of the universe. ![]()
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