Everyone loves a beautiful image of the cosmos, particularly those from our own Milky Way Galaxy, where objects are (relatively) closer to Earth. Given that, this latest image from the European Southern Observatory should not disappoint: It shows not one but two spectacular formations – star cluster NGC 3603 on the left, paired with a collection of glowing gas clouds known as NGC 3576 on the right.

NGC 3603 is about 20,000 light years away from Earth; NGC 3576 is half that, around 9,000 light years.

NGC 3603 is special in out galaxy in that it’s the largest concentration of massive stars known to date. Those at the center – the Wolf-Rayet system – are particularly massive, about 20 times that of the Sun. However, though they’re at an advanced stage of evolution, stellar winds strip off a considerable amount of their surface material at an alarming rate.

The Nebula NGC 3567, though closer, appears next to NGC 3603 in the night sky. According to the ESO, it’s “notable for two huge curved objects resembling the curled horns of a ram.” Those apertures are apparently the result of similar stellar winds performing a similar function, blowing hot gas and dust out into space. The two notably vacant black spots near the top, known as “Blok globules,” are sites where future stars are likely to form.

Both clusters were discovered by English astronomer John Herschel in 1834 from an observatory in Cape Town, South Africa.

NGC 3603 also has the distinction of being a very active formation. According to the ESO:

“Stars are born in dark and dusty regions of space, largely hidden from view. But as the very young stars gradually start to shine and clear away their surrounding cocoons of material they become visible and create glowing clouds in the surrounding material, known as HII regions. HII regions shine because of the interaction of ultraviolet radiation given off by the brilliant hot young stars with the hydrogen gas clouds. HII regions can measure several hundred light-years in diameter, and the one surrounding NGC 3603 has the distinction of being the most massive in our galaxy.”