Latest ESO Image Depicts an Odd Couple Located in the Galaxy Next Door

The latest image to come out of the European Southern Observatory's (ESO) Very Large Telescope (VLT) represents an intriguing star-forming region in one of the Milky Way's satellite galaxies known as the Large Magellanic Cloud (LMC).

Named after the great explorer Magellan, the LMC boasts areas so active in producing new stars they are visible with the naked eye. Smaller -- though no less intriguing -- are the galaxy's lesser nebulae, which telescopes reveal in intricate detail.

In this case, the new VLT image depicts a duo that astronomers describe as an "oddly mismatched pair." They include NCG 2014 and NGC 2020 and, while different in many ways, both were sculpted by powerful stellar winds from extremely hot newborn stars that radiate into the gas, causing them to glow.

Their difference in coloring, meanwhile, is the result of differing chemical makeups as well as the distances between the stars and the respective gas clouds. The pink-tinged NGC 2014 is a glowing cloud of mostly hydrogen gas while NGC 2020 obtains its blueish hue from its abundance of oxygen. In both cases, energetic radiation from new stars strips electrons from the atoms within the surrounding gas, ionizing it and creating a glow. 

In addition to this strong radiation, massive young stars are also responsible for producing powerful stellar winds that eventually cause the gas around them to disperse and stream away. In the case of NGC 2020, a single brilliant and very hot star seems to have started this process, creating a cavity that appears encircled by a bubble-like structure.

All told, the LMC is a mere 163,000 light-years away from the Milk Way -- a stone's throw on a cosmic scale. As a result, astronomers are able to study it in far more detail than more distant systems. In fact, the LMC represented a major motivating factor for the building of telescopes in the southern hemisphere, which eventually led to the establishment of the ESO over 50 years ago.

Though nearby, the LMC is a runt, containing less than one-tenth of the mass of the Milky Way and spanning just 14,000 light-years compared to the Milky Way's estimated 100,000 light-years. Referred to by astronomers as an irregular dwarf galaxy, the LMC's irregularity, combined with its prominent central bar of stars, suggests that interactions with the Milky Way and the nearby galaxy the Small Magellanic Cloud could have played a heavy role in its chaotic shape.