Andromeda

Sometimes I look at an image I've captured, and then I look at the light pollution dome that these photons were extracted from, and I am overwhelmed with the satisfaction of pursuing urban astronomy.

This is our nearest full sized galaxy neighbour, Andromeda aka M31. Unfortunately it's on a collision course with our Milky Way galaxy! We only have 4 billion years left. In truth it will be more of a merger than a collision because there is so much space between stars and planets there will be very few actual collisions.

I made two versions of this image, the one above is without the Milky Way stars (thanks to the miracle of modern image processing). It's sort of like the difference between looking through a screened window and then stepping outside to remove the veil. Here is the same image with all the Milky Way stars in place:

The final images above are a blend of narrowband and wideband images, which means I used various filters to remove light pollution or to extract specific gassy emissions (don't worry, these are the good kind of gassy emissions). Below is an example- using a narrowband filter I captured the glowing Hydrogen gasses that are often a good indication of stellar nurseries:

Here's a breakdown of how the final images were made: The Vixen VSD100F telescope was used at f3 A Central DS 5DMkIV was the camera A Vixen SXP with Starbook TEN was the controller

An ASIAir Pro was the Astro Computer

Images/Filters used were:

35 x 10min frames with Triad Ultra filter

19 x 3min with Optolong L-Pro filter

9 x 5min with Optolong L-Pro filter

5 x 10min with Baader F3 O-III 4nm filter

5 x 10min with Baader F3 Ha 3.5nm filter 5 x 10min with Baader F3 S-II 4nm filter That's a total of 602 minutes, or 10 hours of imaging (not including the discarded frames)

For software I used Pixinsight and Photoshop to calibrate and merge all these images. Here you can see all the different types of frames being brought together in Pixinsight.

Here is more of the field. You can click on it to see all the detail. I set this as my desktop background: