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arXiv · 1911.11735

Asymmetry between galaxies with different spin patterns: A comparison between COSMOS, SDSS, and Pan-STARRS

Lior Shamir
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Abstract

Previous observations of a large number of galaxies show differences between the photometry of spiral galaxies with clockwise spin patterns and spiral galaxies with counterclockwise spin patterns. In this study the mean magnitude of a large number of clockwise galaxies is compared to the mean magnitude of a large number of counterclockwise galaxies. The observed difference between clockwise and counterclockwise spiral galaxies imaged by the space-based COSMOS survey is compared to the differences between clockwise and counterclockwise galaxies imaged by the Earth-based SDSS and Pan-STARRS around the same field. The annotation of clockwise and counterclockwise galaxies is a fully automatic process that does not involve human intervention, and in all experiments both clockwise and counterclockwise galaxies are separated from the same fields. The comparison shows that the same asymmetry was identified by all three telescopes, providing strong evidence that the rotation direction of a spiral galaxy is linked to its luminosity as measured from Earth. Analysis of the luminosity difference using a large number of galaxies from different parts of the sky shows that the difference between clockwise and counterclockwise galaxies changes with the direction of observation, and oriented around an axis.

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Lior Shamir. 2019-11-26. Asymmetry between galaxies with different spin patterns: A comparison between COSMOS, SDSS, and Pan-STARRS. https://arxiv.org/abs/1911.11735

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