Reflection nebula NGC 1788. This is an unusual reflection nebula (bluish white at centre) surrounded by a glowing red ring of hydrogen gas. The stars inside the nebula are young, only around a million years old. The ring of glowing hydrogen gas is energized by nearby hot, massive stars not visible in this image. This image was obtained with the wide-field view of the Mosaic camera on the Mayall 4-metre telescope at Kitt Peak National Observatory. It combines observations in the B (blue), I (orange) and Hydrogen-Alpha (red) filters. The nebula is part of the large Orion Complex of gas and dust, which includes the Orion nebula, which lies around 1500 light years from Earth in the constellation of Orion.