A blue galaxy obscured by excess dust (bludog) photographed by the Subaru telescope. *Naoj HSC Collaboration.
Not all discoveries are truly new. This is the case with the extremely red object (ERO) found in the data of the James Webb Space Telescope (JWST). The analysis shows that they are very similar to the blue excess dust obscuring galaxies (Bludogs) that have already been reported in the Subaru telescope data.
Quasars are one of the brightest objects in the universe and are powered by a supermassive black hole that can reach more than a billion times the mass of the Sun. These objects are the focus of much research, but how they were formed is still poorly understood.
The popular theory is that they form in galaxies with clouds of gas and dust that obscure the growing quasar until it is strong enough to blow up the clouds. If this is true, it should be able to capture the short time frame of the quasar coming out of the clouds.
Due to the short transition period, it is necessary to observe a large number of pre-quasar candidates and hopefully be lucky enough to catch a galaxy when the quasar begins to explode. Judging by the JWST data, a group of polar red objects (ERO) has been identified as possible transitional quasars.
But then researchers at the Subaru Telescope, a Japanese telescope in Hawaii, noticed that despite their "redness," the ero also has an important blue component, similar to the blue excess dust obscuring galaxies (bludog) found in the Subaru telescope's big data, described in a report last year.
Analysis has shown that ero and bludog may be the same class of objects, but there are also important differences. One possibility is that Ero is in an earlier evolutionary stage than Bludog. In order to determine the true relationship between Ero, Bludog, and quasars, a larger sample of candidates needs to be collected.
The latest** was published in the Astrophysical Journal Letters, and the previous findings were published in the Astrophysical Journal.
Larger samples will be studied by next-generation astronomical instruments, including the Infrared Space Telescope project called GREX-plus, which is planned for Japan.
More information: Akatoki Noboriguchi et al., Similarities between dense polar-red objects discovered with JWST at the dawn of the universe and galaxies obscured by blue excess dust known at noon in the universe, Astrophysical Journal Letters (2023). doi： 10.3847/2041-8213/ad0e00