This is Mars in motion over the course of 5 nights - my first detection of a solar system object using an All Sky camera. I hope to use this process to find more objects that move across the night sky, but Mars was an easy one to start with. It's bright and easily visible with the naked eye any night it's above the horizon. My object motion detection program (SkyDelta) works well on it too because it's such a substantial blob. I may write more about the tools I'm using and have written, but first I want to get a reporting format established to encourage me to find more solor system objects and catalog them here. So here's the rundown of my detection of Mars.
1. Original images (cropped and processed) from 5 nights at approximately 10:30pm: 2018-12-31, 2019-01-01, 2019-01-03, 2019-01-05 and 2019-01-06.
2. The same cropped and processed frames aligned with PixInsight.
3. SkyDelta motion detection from aligned frames.
4. SkyDelta cumulative motion detection blobs.
5. Mars is the brightest dot within the red circle. Note the little dipper-like formation to its left.
6. Stellarium sky configuration on the same night. Note the little dipper-like thing again below Mars. The perspective is rotated, but that's just an effect of the camera orientation.
- Images are from the All Sky camera at the beautiful Observatoire de Saint-Veran.
- Processing [image set 1] includes: cropping, bad pixel detection, synthetic dark creation, dark subtraction and histogram stretching.
- Alignment with PixInsight [image set 2] using 2D surface splines and distortion correction. Screenshot.
- SkyDelta detection [image set 3 & 4] using gaussian global thresholding, median-like stacking (percentile level) to create a stationary background star mask, mask expansion and mask subtraction to remove stationary stars from each frame. I also used a median filter to de-speckle the motion detection images which might not work as well for fainter objects or smaller objects.
Published: March 15, 2019