M20 – Trifid Nebula
This Hubble image reveals a star-forming cloud of gas and dust in M20 being torn apart by radiation from a massive nearby star, just beyond the top of the frame. Two thin, finger-like jets protrude from the head of a dense cloud in the upper left of the image, which might be forming new stars at their tips. The jets, each roughly three-quarters of a light-year long, are being eroded by the radiation from the massive star. The red in this image represents hydrogen and sulfur, while green represents oxygen.
Credits: NASA/ESA and Jeff Hester (Arizona State University)