Very Large Telescope Spies on Colorful Nebula in Neighboring Galaxy

This new image from ESO’s Very Large Telescope (VLT), at the Paranal Observatory in Chile, shows the strikingly colorful gas cloud LHA 120-N55(N55 for short), in which the stars are adorned with a mantle of glowing gas.

This image of the emission nebula LHA 120-N55 was acquired using the FORS2 instrument on ESO’s VLT telescope. Image credit: ESO.

N55 is an emission nebula in the Large Magellanic Cloud, a galaxy located approximately 163,000 light-years away in the constellation of Dorado.

This object is situated inside the so-called superbubble LMC 4. Superbubbles are often hundreds of light-years across. They are formed when the fierce winds from newly formed stars and shockwaves from supernova explosions work in tandem to blow away most of the gas and dust that originally surrounded them and create huge bubble-shaped cavities.

The material that became N55, however, managed to survive as a small remnant pocket of gas and dust.

It is now a standalone nebula inside LMC 4 and a grouping of brilliant blue and white stars – known as LH 72 – also managed to form hundreds of millions of years after the events that originally blew up the superbubble.

The stars in LH 72 are only a few million years old, so they did not play a role in emptying the space around N55. The stars instead represent a second round of stellar birth in the region.

The intense light from blue-white stars is stripping nearby hydrogen atoms in N55 of their electrons, causing the gas to glow in a characteristic pinkish color in visible light.

Scientists recognize this telltale signature of glowing hydrogen gas throughout galaxies as a hallmark of fresh star birth.

While things seem quiet in the star-forming region of N55 for now, major changes lie ahead.

Several million years hence, some of the massive and brilliant stars in the LH 72 association will themselves go supernova, scattering N55’s contents.

In effect, a bubble will be blown within a superbubble, and the cycle of starry ends and beginnings will carry on in this close neighbor of our Milky Way Galaxy.