7/11/2023 0 Comments Star shift origins![]() An alliance in name only, it is in reality, a brutal empire. Humans have explored the stars and colonized many worlds under the authority of the Earth Systems Alliance (ESA), a government controlled by powerful interstellar organizations. This article was adapted from Academy website content reviewed by the following experts: Professor Brian Schmidt AC FRS FAA Professor of Astronomy, Research School of Astronomy & Astrophysics, Australian National University Professor Tamara Davis School of Mathematics and Physics, The University of Queensland Dr Brad E.Steam Page for Demo Only view template page Star Shift is an upcoming sci-fi RPG game created by Psychronic Game Studios. But is the expansion rate really constant? Apparently not … and that’s where dark energy comes in. The ratio of the two became the famous ‘Hubble constant’ and represents the expansion rate of the universe. Using various measures to establish how far away the galaxies were, Edwin Hubble (and those that followed him) found that their velocity was always proportional to their distance. A faster-moving object has a greater shift in wavelength. The degree of shift can also give astronomers information about how fast the object is moving relative to us. Notice how the lines shift towards the red end of the spectrum. Bottom: the light spectrum of that object moving away from you. Top: the light spectrum of an object at rest. As this is towards the red end of the spectrum, astronomers call it redshift. In contrast, the light from a star moving away from us seems to shift towards longer wavelengths. Because shorter wavelengths correspond to a shift towards the blue end of the spectrum, this is called blueshift. So, if a star is moving towards Earth, it appears to emit light that is shorter in wavelength compared to a source of light that isn’t moving. This apparent change in wavelength can also be observed for the visible light emitted by stars or galaxies. It just sounds different due to the car’s movement relative to you. There is no actual change in sound the car isn’t making a different noise. This is called the Doppler effect, where waves, in this case sound waves, change in frequency and wavelength as the source moves towards you (higher frequency, shorter wavelength) or away from you (lower frequency, longer wavelength). The noise of a siren or a car speeding past sounds higher in pitch the closer it gets to you and lower as it moves away. Something causes the wavelength of the radiation (emitted by faraway stars and galaxies) to 'stretch'. The further away an object is, the greater the shift. But rather than an actual change in the wavelength, this phenomenon was something similar to the Doppler effect-they only appear stretched relative to the observer. Something causes the wavelength of the radiation to ‘stretch’. When looking at the radiation emitted by distant stars or galaxies, scientists see emission spectra ‘shifted’ towards the red end of the electromagnetic spectrum-the observed wavelengths are longer than expected. One thing they examine is the change in position of lines in the spectrum from a star-this can tell astronomers how far away the star is, whether it is moving towards or away from us and how fast it is moving. ![]() By studying the wavelengths of light (as indicated by ‘lines’ within the electromagnetic spectrum) emitted by an object in space, astronomers can get a range of information. All known elements emit and absorb particular wavelengths of light, which is part of the electromagnetic spectrum.
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