Using the Subaru telescope, an international team of astronomers conducted deep multi-band photometric observations of a dwarf irregular galaxy known as NGC 6822. The Barnard Galaxy (NGC 6822) is about 1.63 million light-years from Earth, which is very close by astronomical standards. However, it is outside the virtual radius of the Milky Way. NGC 6822 is known locally as a dwarf irregular galaxy. Its diameter is about 7000 light years and contains a spatially extended system of spherical clusters (CS). NGC 6822 can be observed from both the northern and southern hemispheres. And close range allows you to conduct many multi-range studies in the range from optical to near infrared (NIR) and medium infrared (MIR). Moreover, its chemical composition and obvious isolation make NGC 6822 a very interesting laboratory for studying stellar pulsation and evolution. A team of astronomers led by Maria Tantalo of the University of Rome Tor Vergata in Italy performed accurate multi-band photometry NGC 6822 using a Hyper-Suprime-Cam (HSC) on the Maunakea Subaru telescope. The HSC data set was supplemented by multi-channel images obtained with a MegaPrime wide-angle camera on the Canada-France-Hawaii Telescope (CFHT), a Dark Energy Camera (DECam) on the Blanco Telescope at the Cerro Tololo Observatory (CTIO) and a WFC wide-angle camera. ), mounted on the Isaac Newton (INT) telescope in La Palma. The Milky Way turned out to be older than scientists thought: a difference of billions of years (video) In images from Mars, ufologists spotted an astronaut on telescopes of a class of 4-8 m », – researchers wrote. As a result, the scientists obtained a set of data covering an area of ​​two square degrees in the center of NGC 6822 with three different photometric bands. In total, scientists have made about 40 million measurements of objects around the field of view. The final catalog includes more than 1 million stars with at least one dimension in two different photometric ranges. It turned out that young, intermediate and old stars in NGC 6822 show different radial distributions. The old stellar population is spherically distributed and extends greater radial distances than previously thought (about 1 degree). As for the young population, it has a well-defined stripe and a disc-shaped distribution, offset from the center. This is compared to the old population. In addition, the study found that carbon-rich stars in NGC 6822 are more concentrated in the center, and their structural parameters are similar to both young and old stellar tracers. Recall that irregular galaxies are irregularly shaped galaxies that do not fit into the Hubble sequence. They have neither spiral nor elliptical structure. Most often, such galaxies have a chaotic shape without a pronounced core and spiral branches

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