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

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.

Multipole alignment in the large-scale distribution of spin direction of spiral galaxies

“…The observations reported in this paper agree with previous observations that show asymmetry between galaxies with opposite spin directions [25,36,37,15,38,39,41,40,42,43], or patterns between spin directions of galaxies that are too far to have gravitational interactions [24]. Cosmologicalscale anisotropy was also observed through short gamma ray bursts, providing evidence of nonuniform distribution that could violate the isotropy assumption of the cosmological principle [26], although long gamma ray bursts show no statistically significant anisotropy [1].…”

“…Automatically annotated datasets of galaxy images showed clear and statistically significant asymmetry between clockwise and counterclockwise galaxies in Sloan Digital Sky Survey [39,41,43]. While the first experiments were based on SDSS alone, more recent work using several telescopes showed very good agreement between SDSS and data collected by other telescopes such as Pan-STARRS [40], and Hubble Space Telescope [42]. Other experiments used smaller manually annotated datasets to show patterns of spin directions of galaxies [44], including galaxies that are too far from each other to have gravitational interactions [24].…”

“…Because the spin direction of a spiral galaxy depends on the perspective of the observer, the distribution of the spin directions of spiral galaxies is expected to be randomly distributed in the sky to an Earth-based observer. However, several previous studies showed evidence of non-random patterns of the distribution of spin directions of spiral galaxies [25,36,37,15,38,39,41,40,23,24,42,43].…”

Analysis of the Alignment of Non-Random Patterns of Spin Directions in Populations of Spiral Galaxies

“…Clearly, more research will be needed to test the possible non-random distribution of galaxies with opposite spin directions, and profile possible patterns that it exhibits if such non-random distribution indeed exists. While the analysis discussed here is based on SDSS data, these observations are aligned with smaller datasets from Pan-STARRS [6] and Hubble Space Telescope [52]. Future analysis will include larger datasets such as the Dark Energy Survey and the Vera Rubin Observatory, providing far larger and deeper datasets.…”

Galaxy spin direction distribution in HST and SDSS show similar large-scale asymmetry

“…Recently, several experiments using large datasets of galaxies imaged by several different instruments have shown evidence of non-random distribution of the spin directions of spiral galaxies (Slosar et al, 2009;Longo, 2011;Shamir, 2012Shamir, , 2013Hoehn & Shamir, 2014;Shamir, 2016bShamir, , 2017cLee et al, 2019a,b;Shamir, 2019Shamir, , 2020a. The asymmetry is reflected by differences in the number of galaxies with opposite spin directions (Shamir, 2012(Shamir, , 2019(Shamir, , 2020cLee et al, 2019b), and it changes with the directions of observation (Shamir, 2012) and the redshift (Shamir, 2016a(Shamir, , 2019(Shamir, , 2020c.…”