By Jett Peters
Today, I was hoping to illustrate the difference between an image with and without stars in an area of dense nebulosity. This is an image of the Bubble Nebula region (taken from UDRO) in a modified SHO color palette. SHO, also known as the Hubble palette, is a non-natural color mapping where we map HA to green, SII to red, and OIII to blue. In this image, pixel math has been used to give the image a blue and gold color.
Starless courtesy of StarX
As you can see the starless image reveals much more of the underlying nebulosity. This region is home to a number of well-known nebulae. The below image shows an annotated HA image of the region, hopefully offering some fun future target ideas.
The best known is the Bubble Nebula. This nebula has a fun challenge associated with it. Hubble imaged this nebula back in 2016, and it has become somewhat of a trend to shoot the region and see how close you can get to Hubble’s level of detail. Many amateurs are surprised by how close they can get. Below is my attempt at this challenge. This is a zoom-in on the bubble from the previously shown image albeit in a slightly different palette (true SHO).
Another target in this region is NGC 7538. This target is often overlooked, but it has some very interesting details. It’s relatively small so maybe best to stick with large telescopes for this one, but below is the shot from my Esprit 100.
