Yesterday we experienced one of those small historical moments that, very occasionally, allows us to experience astrophysics: we saw, live and direct, the first real photograph of Sgt A*, the “monstrous black hole that lives in the center of our galaxy”. However, by chance, this announcement coincided with the acceptance of a piece of paper that threatens to spoil all this astrophysical party and send all the articles, reports and radio cuts to the trash of history: an analysis that ensures that, with the data of the previous photograph in hand, everything could be wrong.
What if the photos are wrong?. What explained Miguel Santandera few days ago the Astrophysical Journal accepted an article which revisited public data from the Event Horizon Telescope to independently reconstruct the photograph of the black hole in the galaxy M87 that we were able to see in 2019.
His conclusions are dynamite. According to the researchers, the famous ring could be essentially “an image artifact caused by field of view observations”. According to the analyzes and simulations they handle, the narrowness of the EHT’s field of view can cause a kind of “visual effect” that makes us see a ring where there is none.
That is, we have found what we expected to find, yes; but not because it is in the data, but because of a) a bias related to the maximum separation between the radio telescopes that make up the telescope and b) we had designed the controls to encounter a ring. We would be celebrating an error, an enormous pareidolia; we would be “seeing faces” in an image that does not contain them.
The hypothesis of the Japanese research team is very suggestive and has managed to pass the filters of one of the most prestigious magazines in the field. However, that does not mean they are right. Now, it’s time to review the problems they point out and analyze whether the rings of black holes are really the product of too narrow a field of view.
What would happen if it is confirmed?. The reality is that nothing. Or, well, beyond the initial disappointment: very little. The EHT would go to work to remedy these problems and possibly bring to the table the need to build an even larger telescope. Something similar to what we have with LISA for gravitational waves.
However, deep down, it is a new reminder that science is an ongoing project and that (almost) everything is subject to revision. That is the beauty, the strength and the weakness of the best knowledge that we are capable of generating.