So I figured out a method that works which is not really how I wanted it to work.
I needed to upload the image directly through wordpress media.
Which is stored in
I wanted the images to be inside the themes folder
but for some odd reason the files are being corrupted. (hence the broken image file)
After uploading directly to the uploads folder I was able to use the tag I had originally.
<img class ="nightsky" src="https://mywesbiteurl.com/wp-content/uploads/2018/12/hrtbrk.png" alt="" >