The image below shows hot gas in the supernova remnant N49 in the Large Magellanic Cloud (LMC). Emission from hydrogen atoms (red), oxygen ions (green) and neon ions (blue) lies in filaments where the gas has been heated and compressed by a shock wave driven by the explosion of a massive star. The red, green and blue colors show gas at temperatures of about 8,000, 100,000 and 300,000 degrees, respectively. The images were obtained with the Magic camera on the Clay Telescope in Chile by Cara Rakowski and John Raymond.

N49 is the brightest supernova remnant in the LMC. A massive star produced a strong wind that cleared a low density bubble around it. When the star exhausted its supply of hydrogen, it exploded, sending a shock wave throught he interstellar gas. The shock wave has now encountered the shell of dense gas at the edge of the bubble, especially in the lower left part of the image. In the dense gas, the shock slows to 100 - 300 km/s and produces bright emission from neutral hydrogen, doubly ionized oxygen and four-times ionized neon. The neon emission is difficult to detect because it lies in the near Ultraviolet part of the spectrum It is important for filling the gap between emission at visible wavelengths produced by 100 km/s shock waves and X-ray emission produced by shocks faster than 500 km/s.