This is the dwarf galaxy known as NGC 1140. It lies 60 million light-years away in the constellation of Eridanus. It has an irregular form, much like the Large Magellanic Cloud, a small galaxy that orbits the Milky Way. This small galaxy is undergoing a starburst. Despite being only about one-tenth the size of the Milky Way, it is creating stars at about the same rate—the equivalent of one star the size of our sun being created per year. The galaxy is full of bright, blue-white, young stars.
Galaxies like NGC 1140 are of particular interest to astronomers because their composition makes them similar to the intensely star-forming galaxies in the early Universe, and those early Universe galaxies were the building blocks of present-day large galaxies like our Milky Way. Because they are so far away, the early Universe galaxies are harder to study, so these closer starbursting galaxies are a good substitute for studyingt galaxy evolution.
Its vigorous star formation eventually will have a very destructive effect on this small dwarf galaxy. When the larger stars in the galaxy die and explode as supernovae, the gas blown into space may escape the gravitational pull of the galaxy. The ejection of gas from the galaxy throws away one of the building blocks for future star formation. Thus, NGC 1140’s starburst cannot last for long.
Image Credit: ESA