Cosmic Palette

Back in 2010 I captured a wide-field mosaic of the Rho Ophiuchus area that overtime became one of my “signature” deep sky images. I captured that image with broadband filters – in plain language, the colors of the rainbow. A few years later, checking some data and sky surveys, I noticed that in this area there were also some very clearly delimited nebulosity emitting light in the very narrow Hydrogen Alpha band (red) that however were not showing in my original image – or in many of other images of this area. So, I spent some hours capturing H-Alpha data in this area. I then integrated this data with the previous image and voila! Nebulosity that was invisible in my previous image, suddenly appeared. The “new” emission nebulosity is most apparent, as you can see, in the left area of the image, particularly around the stars Delta Scorpii (SH2-7) and Pi Scorpii (SH2-1).