IZw18 is a dwarf galaxy that has helped scientists know what the Universe was like after the Big Bang. The IZw18 galaxy is the poorest in metals that exists in the nearby Universe, but it is also one that most closely resembles the first galaxies that originated, about 13.3 billion years ago.
Thanks to the work done by the Institute of Astrophysics of Andalusia, it is known that in this small galaxy there is a large region of ionized helium, something more typical of galaxies that are much further away and that have little abundance of metals. In order for the ionization of helium to occur, the presence of objects that emit great radiation is necessary, the one necessary to extract electrons from helium atoms.
To get the first detailed map of this region of the IZw18 galaxy, the researchers used the PMAS integral field spectrograph of the 3.5-meter telescope at the Calar Alto Observatory, located in the Sierra de Los Filabres, north of Almería, in Andalusia.
IZW 18 is a galaxy that tends towards the red color within the electromagnetic spectrum. This is because it is forming new stars with little abundance of metals and a lot of gas in the form of hydrogen. The radiation field emitted by this galaxy is 200 times more intense than we experienced in the Milky Way.