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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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Large‐scale asymmetry between clockwise and counterclockwise galaxies revisited
Abstract The ability of digital sky surveys to collect and store very large amounts of data provides completely new ways to study the local universe. Perhaps one of the most provocative observations reported with such tools is the asymmetry between galaxies with clockwise and counterclockwise spin patterns. Here, I use∼1.7 × 105spiral galaxies from Sloan Digital Sky Survey (SDSS) and sort them by their spin patterns (clockwise or counterclockwise) to identify and profile a possible large‐scale pattern of the distribution of galaxy spin patterns as observed from Earth. The analysis shows asymmetry between the number of clockwise and counterclockwise spiral galaxies imaged by SDSS and a dipole axis. These findings largely agree with previous reports using smaller datasets. The probability of the differences between the number of galaxies occurring by chance isp< 4 × 10−9, and the probability of an asymmetry axis occurring by mere chance isp< 1.4×10−5.
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- Award ID(s):
- 1903823
- PAR ID:
- 10145699
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Astronomische Nachrichten
- Volume:
- 341
- Issue:
- 3
- ISSN:
- 0004-6337
- Page Range / eLocation ID:
- p. 324-330
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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