Scanning Orion spur…
The Pillars of Creation

Nebula

A vast cloud of gas and dust — the birthplace of stars. Gravity pulls pockets of hydrogen together until the pressure at their cores ignites nuclear fusion. The young stars illuminate the remaining nebula from within, carving out pillars and cavities with their intense radiation. Every star you see in the night sky began inside a cloud like this one.
COMPOSITIONH (74%) · He (24%) · dust (2%)
SPAN~24 light-years
PROTOSTARS FORMING3
TEMP (HOTSPOTS)~10,000 K
The faint glow comes from hydrogen excited by ultraviolet radiation from nearby massive stars. This is the same process that makes neon signs glow.
Hydrogen (Hα)
Oxygen (O III)
Sulfur (S II)
Protostar