Something happened. You may have forgotten to take flats or there’s a defect that doesn’t calibrate out. You may still be able to recover your image with a synthetic flat frame. This Pixinsight workflow will get you to a usable image and will work for gradients, dust motes, and other issues.
Remote Telescopes: Imaging From a Distance
After a dry summer and devastating wildfires, it’s finally raining here. I’m glad we’re getting the moisture, but my astrophotography goes idle for weeks on end at this time of year. So I’m exploring the world of remote telescope services.