While taking a picture of Barnard's Star, I noticed this.
These were taken 50 days apart, and the star is not there in the
newer picture.

ISO 6400 1s f/5.7
50 light frames, 20 dark frames
Stacked in DSS

Explanations sorted by likelihood:
- crud on camera sensor
- processing glitch
- Variable star, or dust
- It just disappeared or something
- Aliens???

https://nova.astrometry.net/user_images/4792721

RA: 17h 56m 24.6s | Dec: +03:22:41