Related Clues:
- 2013's ISON, for one
- Cupid's sleighmate
- PBS show with episodes about tornadoes and catacombs and the like
- Scene of runaway nuclear fusion
- One of Santa's sleigh team
- PBS series since '74
- Star that ejects a cloud, thus becoming brighter
- Distant flare-up
- Hale-Bopp, e.g
- Halley's discovery
- Halley's sighting
- Astronomical flash
- Launch attack to repel a potential space invader
- Almost add up to 5, perhaps?
- Star and famous lover half falling out