I played a Halley's Comet themed game in 1984 that was called Constellations. I've only been able to find it on Ebay so far: https://www.ebay.com.au/itm/Vintage-Game-Circa-1984-Constellations-Darryl-Hemsley-Adelaide-Basket-Range-/382983024814. I can't find it on Board Game Geek.
You had to collect three pieces of a comet, the "head", the "body", and the "tail". Each piece was a square piece of cardboard, with a third of a comet on one side and various "constellations" (squares or lines of four stars) on the other side. There was much more to the game than that, but that's all I can remember.
How can I find the complete rules?