Independent reanalysis of the M87 galactic center radio observational data
Radio images obtained from the reanalysis, showing the center of the elliptical galaxy M87. The upper left panel shows a close-up around the black hole, depicting the “core” (the red, round spot in the lower center) and “knots” (elongated spots on the center right and lower right). The wide-field image shows the jet extending diagonally to the upper right. The red spot on the right edge is a not real structured but an artifact created by the imaging method. Credit: Miyoshi et al

According to a new study, an independent reanalysis of the event horizon telescope's observational data has resulted in different images. In modern science observational data and analysis methods are open to the public and discussed in various communities of researchers to produce more credible results.

The methods by which the data were analyzed have been made available to the public worldwide. The data and methods have been reanalyzed by researchers not involved in the EHT. Various teams have published their reanalysis results.

A research team consisting of the assistant professor at NAOJ, the contract researcher at RIKEN, and the professor at Kobe University reanalyzed the data with standard tools. The images show a "core" at the center of the universe, as well as the astrophysical jet that extends from it.

There are many black holes that emit astrophysical jets, but the one extending from the center of M87 has been studied many times. The research team believes that the base of the jet is what they have found. The 40 micro-arcsecond ring structure seen in the EHT image is likely a result of the lack of sufficient data to resolve 40 micro-arcsecond structures, as compared to the data for the structures of other sizes.

This study shows the importance of the sensible, normal process that modern science should follow. More credible insights into M87's center and the structure of the jet are expected from further data reanalysis, method examination, and follow up observations.

More information: Makoto Miyoshi et al, The Jet and Resolved Features of the Central Supermassive Black Hole of M87 Observed with the Event Horizon Telescope (EHT), The Astrophysical Journal (2022). DOI: 10.3847/1538-4357/ac6ddb Journal information: Astrophysical Journal