Space is black. I mean, duh, right? But really, it's black because it's almost entirely empty, so even with stars scattered around, there's nothing to light up.
But some parts of space are bright: clouds of gas can be lit up by nearby stars, making them glow. However, just to make things more fun, there can be thicker patches of dust mixed in that block the light from the stars and gas behind them. We see lots of those, they're pretty common. But there's yet another "however": that dust only blocks the visible light. In the infrared, that dust should itself glow because it's warm. NGC 1999 -- seen here in a famous Hubble picture -- has all these ingredients. It's a thick region of gas and dust. Stars are being born in and around it, brightening it with their reflected light (as seen in the image; the star V380 ...
