Nebula - HD Stockvideo

"Animation of a flight into an emission nebula, showing a massive hot young star whose radiation causes the nebular to glow. Emission nebulae are starbirth regions, where huge clouds of gas and dust contract through gravity until regions become hot and dense enough for stellar nuclear reactions to begin. This process can produce massive stars, which burn far more brightly than the sun, emitting a huge amount of ultraviolet radiation. This radiation excites atoms in the remaining gas in the nebula, causing it to emit light as it returns to its ground state."