IC 1284 Emission Reflection Nebula

Photographed at Kitt Peak Observatory, July 2003
Image Processing by Julia Schwartz, DSHS '04

IC 1284, a star cluster within a nebula, is located in the constellation Sagittarius, just below the bright M24 nebula (Della Caustiche). Nebulae are accumulations of interstellar gases and dust lying within the galaxy; the waste products left behind from exploding stars will often form new stars over time. IC 1284 is primarily an emission nebula, meaning that its gaseous clouds are glowing due to the electromagnetic radiation from the hot stars being born within it. The stars in emission nebulas have such an excess of charged hydrogen energy that the extra energy is released by emitting light. IC 1284 also is partially a reflection nebula, which is a nebula that scatters light into our line of sight.

The variety of colors shown above is a result of the varying temperatures of the objects within the nebula. Emission nebulae emit radiation mainly at a wavelength of 656.3 nanometers, in the red end of the electromagnetic spectrum. Thus, the main nebular image shown was picked up by a hydrogen alpha filter, which allows in light at the precise wavelength of 656.3 nm. The blue stars shown in the image are picked up by a blue filter, which allows in light at wavelengths roughly between 380 and 480 nm, or at temperatures of above 6000 C, hotter than the Sun. The red stars, highlighted by an infrared filter, represent light at wavelengths between 760 and 850 nm, or at temperatures less than that of the sun: below 5000 C.

Right Ascension of IC 1284: 274.4
Declination: -19.7