N44 is a complex nebula filled with bright hydrogen, dark dust lines, massive stars and many groups of stars of different ages. However, one of its most notable features is the dark gaps in the starry sky called “super bubbles”, which can be seen in this image of the upper region of the Hubble Space Telescope.
The hole is about 250 light-years wide, and its existence is still a mystery. The stellar wind blown away by the massive stars in the bubble may blow away the gas, but this is not consistent with the wind speed measured in the bubble. Considering that the nebula is full of massive stars that will die in the explosion of the Titanic, another possibility is that the expanding layers of old supernovae carve out cosmic caves.
Astronomers discovered a supernova remnant near the super bubble and determined that there is an age difference of approximately 5 million years between the stars inside and on the edge of the super bubble, indicating the existence of multiple star formation events in a chain reaction. The dark blue area around 5 o’clock around the super bubble is one of the hottest areas in the nebula and the area where star formation is most intense.
N44 is an emission nebula, which means that its gas has been excited or ionized by radiation from nearby stars. When the ionized gas begins to cool from a high-energy state to a low-energy state, it emits energy in the form of light, making the nebula glow. N44 is located in the Large Magellanic Cloud, spanning approximately 1,000 light-years and is approximately 170,000 light-years away from Earth.