Sharpless 140 - Sh2 140
Camera: Starlight Xpress SXVF-H16
Mount: Losmandy G-11 with Gemini
Scope: Astro Physics AP130 EDF F/6
Colors: HaLRGB
Exposure Time: Various
Post-Production: MaxIm DL, CCDStack, PixInsight, and Photoshop CS5
This nebula is along the northeast circumference of a large molecular cloud called the Cepheus Bubble: a a bubble of gas and dust that is around 500 light years across and approximately 2,700 light years away. From our vantage point here on earth, the Cepheus Bubble extends across 10 degrees of sky! The bubble is a fairly recent part of the sky... at least in astronomical time, having formed only 10-20 million years ago inside one of the outer spiral arms of our galaxy. Early massive stars that formed in the center of the bubble quickly exploded, marking the origin of this molecular cloud. The subsequent compression wave of gas triggered the formation of new stars, especially along the edges of the bubble where the gas is most dense. SH2-140 is one of those regions.